4.0 SOHC no spark after engine replacement
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From: Camden ar
4.0 SOHC no spark after engine replacement
2003 ford ranger.
no spark after engine replacement. New engine from ford. I for sure have fuel, I have 1.5 volts going to new crank sensor. I have power to coil. I'm at a loss. I don't have any power to my cam sensor connector. This truck set up for 5 years..
no spark after engine replacement. New engine from ford. I for sure have fuel, I have 1.5 volts going to new crank sensor. I have power to coil. I'm at a loss. I don't have any power to my cam sensor connector. This truck set up for 5 years..
The Crank sensor and Cam sensor are VR(variable reluctance) sensors, so they generate their own AC voltage, they are not powered by the vehicle systems, just FYI
When you turn on the key the CEL(check engine light) should come on, that means Computer has booted up OK, no CEL means no computer and no start
If CEL is on then try to start, CEL should go OFF as soon as engine is spinning, that means Crank sensor is sending a good timing signal, if CEL stays on then no crank sensor signal and no start
+1 ^^^
50/50 test
Spray fuel into the engine
Try to start
If it start runs and dies, spark is OK but fuel system is not
If it doesn't fire then spark(OR compression) is the issue
50/50 instant results
Since its a "new" engine, which means "NEVER EVER TESTED now-a-days, and you get a no Fire on 50/50 test, I would test compression on at least 2 cylinders, easiest ones to get at
Compression is mechanical, so either good or bad, no wiring or computers involved, lol, so once its off the table as the problem then you can move on to spark and fuel issues
When you turn on the key the CEL(check engine light) should come on, that means Computer has booted up OK, no CEL means no computer and no start
If CEL is on then try to start, CEL should go OFF as soon as engine is spinning, that means Crank sensor is sending a good timing signal, if CEL stays on then no crank sensor signal and no start
+1 ^^^
50/50 test
Spray fuel into the engine
Try to start
If it start runs and dies, spark is OK but fuel system is not
If it doesn't fire then spark(OR compression) is the issue
50/50 instant results
Since its a "new" engine, which means "NEVER EVER TESTED now-a-days, and you get a no Fire on 50/50 test, I would test compression on at least 2 cylinders, easiest ones to get at
Compression is mechanical, so either good or bad, no wiring or computers involved, lol, so once its off the table as the problem then you can move on to spark and fuel issues
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From: Camden ar
So I have compression, I opened the valve on the fuel rail and I have fuel. Still no spark. Cam sensor is good. What's the next move?
The Crank sensor and Cam sensor are VR(variable reluctance) sensors, so they generate their own AC voltage, they are not powered by the vehicle systems, just FYI
When you turn on the key the CEL(check engine light) should come on, that means Computer has booted up OK, no CEL means no computer and no start
If CEL is on then try to start, CEL should go OFF as soon as engine is spinning, that means Crank sensor is sending a good timing signal, if CEL stays on then no crank sensor signal and no start
+1 ^^^
50/50 test
Spray fuel into the engine
Try to start
If it start runs and dies, spark is OK but fuel system is not
If it doesn't fire then spark(OR compression) is the issue
50/50 instant results
Since its a "new" engine, which means "NEVER EVER TESTED now-a-days, and you get a no Fire on 50/50 test, I would test compression on at least 2 cylinders, easiest ones to get at
Compression is mechanical, so either good or bad, no wiring or computers involved, lol, so once its off the table as the problem then you can move on to spark and fuel issues
When you turn on the key the CEL(check engine light) should come on, that means Computer has booted up OK, no CEL means no computer and no start
If CEL is on then try to start, CEL should go OFF as soon as engine is spinning, that means Crank sensor is sending a good timing signal, if CEL stays on then no crank sensor signal and no start
+1 ^^^
50/50 test
Spray fuel into the engine
Try to start
If it start runs and dies, spark is OK but fuel system is not
If it doesn't fire then spark(OR compression) is the issue
50/50 instant results
Since its a "new" engine, which means "NEVER EVER TESTED now-a-days, and you get a no Fire on 50/50 test, I would test compression on at least 2 cylinders, easiest ones to get at
Compression is mechanical, so either good or bad, no wiring or computers involved, lol, so once its off the table as the problem then you can move on to spark and fuel issues
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From: Camden ar
Thank you all for your help. I went thru some troubleshooting and decided to replace the "new" crankshaft sensor with another one. The truck busted right off. So currently it's running, the only issues I'm having is bank 2 is way over fueling. Any ideas on that? It's smoking really bad and won't go below 2500 rpm's while idling.
O2 sensor plug ins, check these since wire harness was moved out of the way to install new engine
All O2 sensor plugs are the same, if you were to Reverse Bank 1 and Bank 2 upstream O2 sensors you would get what you have
The 4 O2 wires that are attached to the sensor are all the same colors, but the Truck side O2 connectors have different colors for bank 1 and bank 2
In 2003
Bank 1 O2 should have a red/white wire as 1 of the 4
Bank 2 O2 a Red/black wire
You just need to confirm one bank has correct wire
Do "Clear Flooded Engine" test
Key on
Press gas pedal down to the floor and hold it down, this TURNS OFF the fuel injector pulses
Crank engine over
It should NOT START or even fire, spark is on but injectors are OFF
If engine starts shut it off and do next test
(Clear Flooded Engine test only works if throttle is Wide Open, so if engine started, shut it off, put a stick on gas pedal to hold it down all the way, then go to engine bay and see if you can open throttle a bit more, if so then gas pedal/throttle cable can not get Wide Open, if so, then Google: Ranger throttle cable mod, easy fix, then re-try Clear Flooded Engine test)
Unplug coil packs 4 wire connector, you want a no start/no spark
Turn key on and off 3 times, primes the fuel system 3 times
Press gas pedal down to floor and hold it down all the way, Clear Flooded Engine test
crack engine over for 5 seconds or so
Pull out spark plugs and check the tips for fuel, all should be DRY, unless an injector is stuck partially open, or its wire is shorted to ground
Check BOTH banks, 1 passenger side and 2 drivers side, you need a comparison
All O2 sensor plugs are the same, if you were to Reverse Bank 1 and Bank 2 upstream O2 sensors you would get what you have
The 4 O2 wires that are attached to the sensor are all the same colors, but the Truck side O2 connectors have different colors for bank 1 and bank 2
In 2003
Bank 1 O2 should have a red/white wire as 1 of the 4
Bank 2 O2 a Red/black wire
You just need to confirm one bank has correct wire
Do "Clear Flooded Engine" test
Key on
Press gas pedal down to the floor and hold it down, this TURNS OFF the fuel injector pulses
Crank engine over
It should NOT START or even fire, spark is on but injectors are OFF
If engine starts shut it off and do next test
(Clear Flooded Engine test only works if throttle is Wide Open, so if engine started, shut it off, put a stick on gas pedal to hold it down all the way, then go to engine bay and see if you can open throttle a bit more, if so then gas pedal/throttle cable can not get Wide Open, if so, then Google: Ranger throttle cable mod, easy fix, then re-try Clear Flooded Engine test)
Unplug coil packs 4 wire connector, you want a no start/no spark
Turn key on and off 3 times, primes the fuel system 3 times
Press gas pedal down to floor and hold it down all the way, Clear Flooded Engine test
crack engine over for 5 seconds or so
Pull out spark plugs and check the tips for fuel, all should be DRY, unless an injector is stuck partially open, or its wire is shorted to ground
Check BOTH banks, 1 passenger side and 2 drivers side, you need a comparison
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From: Camden ar
O2 sensor plug ins, check these since wire harness was moved out of the way to install new engine
All O2 sensor plugs are the same, if you were to Reverse Bank 1 and Bank 2 upstream O2 sensors you would get what you have
The 4 O2 wires that are attached to the sensor are all the same colors, but the Truck side O2 connectors have different colors for bank 1 and bank 2
In 2003
Bank 1 O2 should have a red/white wire as 1 of the 4
Bank 2 O2 a Red/black wire
You just need to confirm one bank has correct wire
Do "Clear Flooded Engine" test
Key on
Press gas pedal down to the floor and hold it down, this TURNS OFF the fuel injector pulses
Crank engine over
It should NOT START or even fire, spark is on but injectors are OFF
If engine starts shut it off and do next test
(Clear Flooded Engine test only works if throttle is Wide Open, so if engine started, shut it off, put a stick on gas pedal to hold it down all the way, then go to engine bay and see if you can open throttle a bit more, if so then gas pedal/throttle cable can not get Wide Open, if so, then Google: Ranger throttle cable mod, easy fix, then re-try Clear Flooded Engine test)
Unplug coil packs 4 wire connector, you want a no start/no spark
Turn key on and off 3 times, primes the fuel system 3 times
Press gas pedal down to floor and hold it down all the way, Clear Flooded Engine test
crack engine over for 5 seconds or so
Pull out spark plugs and check the tips for fuel, all should be DRY, unless an injector is stuck partially open, or its wire is shorted to ground
Check BOTH banks, 1 passenger side and 2 drivers side, you need a comparison
All O2 sensor plugs are the same, if you were to Reverse Bank 1 and Bank 2 upstream O2 sensors you would get what you have
The 4 O2 wires that are attached to the sensor are all the same colors, but the Truck side O2 connectors have different colors for bank 1 and bank 2
In 2003
Bank 1 O2 should have a red/white wire as 1 of the 4
Bank 2 O2 a Red/black wire
You just need to confirm one bank has correct wire
Do "Clear Flooded Engine" test
Key on
Press gas pedal down to the floor and hold it down, this TURNS OFF the fuel injector pulses
Crank engine over
It should NOT START or even fire, spark is on but injectors are OFF
If engine starts shut it off and do next test
(Clear Flooded Engine test only works if throttle is Wide Open, so if engine started, shut it off, put a stick on gas pedal to hold it down all the way, then go to engine bay and see if you can open throttle a bit more, if so then gas pedal/throttle cable can not get Wide Open, if so, then Google: Ranger throttle cable mod, easy fix, then re-try Clear Flooded Engine test)
Unplug coil packs 4 wire connector, you want a no start/no spark
Turn key on and off 3 times, primes the fuel system 3 times
Press gas pedal down to floor and hold it down all the way, Clear Flooded Engine test
crack engine over for 5 seconds or so
Pull out spark plugs and check the tips for fuel, all should be DRY, unless an injector is stuck partially open, or its wire is shorted to ground
Check BOTH banks, 1 passenger side and 2 drivers side, you need a comparison
thanks so much. I will get on this as soon as I get home. One more question.. is there a diagram for vaccuum lines? Also, how many 02 sensors are there? I'm only finding 3.
On V6 engine with single exhaust to rear 3 O2s would be correct
The Left and Right upstream O2 sensors are used to give feedback to computer for correct air/fuel mix
Then a 3rd O2 after the Cat converter(s) to test that its working, cleaning up the exhaust, this one doesn't effect air/fuel mix much but can cause richer running when its gets older
O2s are the ONLY sensors that wear out, have a time limit, 100k miles or 12 years, and they start to run out of the chemicals they need to detect Oxygen in the exhaust
Vacuum diagram is on the radiator support with Emissions label, not easy to follow but that's really all there is even in Ford Shop Manuals, they are like wiring diagrams in that respect, they show whats connected to what but not the pathway thru and around the engine
i.e. Battery +--------------------------starter motor
Doesn't say where the cable runs, just where the two ends should be connected
The Left and Right upstream O2 sensors are used to give feedback to computer for correct air/fuel mix
Then a 3rd O2 after the Cat converter(s) to test that its working, cleaning up the exhaust, this one doesn't effect air/fuel mix much but can cause richer running when its gets older
O2s are the ONLY sensors that wear out, have a time limit, 100k miles or 12 years, and they start to run out of the chemicals they need to detect Oxygen in the exhaust
Vacuum diagram is on the radiator support with Emissions label, not easy to follow but that's really all there is even in Ford Shop Manuals, they are like wiring diagrams in that respect, they show whats connected to what but not the pathway thru and around the engine
i.e. Battery +--------------------------starter motor
Doesn't say where the cable runs, just where the two ends should be connected
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From: Camden ar
On V6 engine with single exhaust to rear 3 O2s would be correct
The Left and Right upstream O2 sensors are used to give feedback to computer for correct air/fuel mix
Then a 3rd O2 after the Cat converter(s) to test that its working, cleaning up the exhaust, this one doesn't effect air/fuel mix much but can cause richer running when its gets older
O2s are the ONLY sensors that wear out, have a time limit, 100k miles or 12 years, and they start to run out of the chemicals they need to detect Oxygen in the exhaust
Vacuum diagram is on the radiator support with Emissions label, not easy to follow but that's really all there is even in Ford Shop Manuals, they are like wiring diagrams in that respect, they show whats connected to what but not the pathway thru and around the engine
i.e. Battery +--------------------------starter motor
Doesn't say where the cable runs, just where the two ends should be connected
The Left and Right upstream O2 sensors are used to give feedback to computer for correct air/fuel mix
Then a 3rd O2 after the Cat converter(s) to test that its working, cleaning up the exhaust, this one doesn't effect air/fuel mix much but can cause richer running when its gets older
O2s are the ONLY sensors that wear out, have a time limit, 100k miles or 12 years, and they start to run out of the chemicals they need to detect Oxygen in the exhaust
Vacuum diagram is on the radiator support with Emissions label, not easy to follow but that's really all there is even in Ford Shop Manuals, they are like wiring diagrams in that respect, they show whats connected to what but not the pathway thru and around the engine
i.e. Battery +--------------------------starter motor
Doesn't say where the cable runs, just where the two ends should be connected
Is it near the Coil pack?
Coil pack had a "AM radio noise suppressor" called a condenser, on one of its bolts, one wire plug, might look like this: https://i.ebayimg.com/images/g/j3gAA...Uq/s-l960.webp
Turn key on, test if that plug has 12v, if so that's probably what its for
Also its wire color would match the Coil Packs 12v wire color, red/??
Not many 1 wire connectors other than that one
Coil pack had a "AM radio noise suppressor" called a condenser, on one of its bolts, one wire plug, might look like this: https://i.ebayimg.com/images/g/j3gAA...Uq/s-l960.webp
Turn key on, test if that plug has 12v, if so that's probably what its for
Also its wire color would match the Coil Packs 12v wire color, red/??
Not many 1 wire connectors other than that one
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From: US
In your last pic, the "RadioNoiseCapacitor\Condensor\Suppressor"
is shown mounted on the corner of CoilPack; has a 1wire pigtail+plug that connects into CoilPack 12v supply wire.
Commonly unplugged\forgotten during engin work, results in SoundSystemSpeaker noise varying with EnginRPMs.
Click here for Pic.
is shown mounted on the corner of CoilPack; has a 1wire pigtail+plug that connects into CoilPack 12v supply wire.
Commonly unplugged\forgotten during engin work, results in SoundSystemSpeaker noise varying with EnginRPMs.
Click here for Pic.
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From: Camden ar
On V6 engine with single exhaust to rear 3 O2s would be correct
The Left and Right upstream O2 sensors are used to give feedback to computer for correct air/fuel mix
Then a 3rd O2 after the Cat converter(s) to test that its working, cleaning up the exhaust, this one doesn't effect air/fuel mix much but can cause richer running when its gets older
O2s are the ONLY sensors that wear out, have a time limit, 100k miles or 12 years, and they start to run out of the chemicals they need to detect Oxygen in the exhaust
Vacuum diagram is on the radiator support with Emissions label, not easy to follow but that's really all there is even in Ford Shop Manuals, they are like wiring diagrams in that respect, they show whats connected to what but not the pathway thru and around the engine
i.e. Battery +--------------------------starter motor
Doesn't say where the cable runs, just where the two ends should be connected
The Left and Right upstream O2 sensors are used to give feedback to computer for correct air/fuel mix
Then a 3rd O2 after the Cat converter(s) to test that its working, cleaning up the exhaust, this one doesn't effect air/fuel mix much but can cause richer running when its gets older
O2s are the ONLY sensors that wear out, have a time limit, 100k miles or 12 years, and they start to run out of the chemicals they need to detect Oxygen in the exhaust
Vacuum diagram is on the radiator support with Emissions label, not easy to follow but that's really all there is even in Ford Shop Manuals, they are like wiring diagrams in that respect, they show whats connected to what but not the pathway thru and around the engine
i.e. Battery +--------------------------starter motor
Doesn't say where the cable runs, just where the two ends should be connected
After engine is warned up, 5min, let it idle and unplug the IAC Valve's 2 wire connector
IAC Valve will close and idle should drop to 600rpm or so, barely running, or it may even stall, either is good it means IAC Valve was working(not stuck) and no vacuum leaks
If it doesn't drop then you have an air leak, or a stuck throttle plate or a stuck IAC Valve
Adding Fuel doesn't increase RPMs, AIR DOES, that's the point of having a "throttle plate" on a gasoline engine
(Diesel engines use fuel to increase RPMs, this is not a diesel)
As you open the throttle plate and let in more air RPMs go up, THEN more fuel is added by the computer
If you add more fuel at idle you will get an increase in RPMs and then engine will struggle and stall as it "floods out"
IAC Valve will close and idle should drop to 600rpm or so, barely running, or it may even stall, either is good it means IAC Valve was working(not stuck) and no vacuum leaks
If it doesn't drop then you have an air leak, or a stuck throttle plate or a stuck IAC Valve
Adding Fuel doesn't increase RPMs, AIR DOES, that's the point of having a "throttle plate" on a gasoline engine
(Diesel engines use fuel to increase RPMs, this is not a diesel)
As you open the throttle plate and let in more air RPMs go up, THEN more fuel is added by the computer
If you add more fuel at idle you will get an increase in RPMs and then engine will struggle and stall as it "floods out"
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From: Camden ar
After engine is warned up, 5min, let it idle and unplug the IAC Valve's 2 wire connector
IAC Valve will close and idle should drop to 600rpm or so, barely running, or it may even stall, either is good it means IAC Valve was working(not stuck) and no vacuum leaks
If it doesn't drop then you have an air leak, or a stuck throttle plate or a stuck IAC Valve
Adding Fuel doesn't increase RPMs, AIR DOES, that's the point of having a "throttle plate" on a gasoline engine
(Diesel engines use fuel to increase RPMs, this is not a diesel)
As you open the throttle plate and let in more air RPMs go up, THEN more fuel is added by the computer
If you add more fuel at idle you will get an increase in RPMs and then engine will struggle and stall as it "floods out"
IAC Valve will close and idle should drop to 600rpm or so, barely running, or it may even stall, either is good it means IAC Valve was working(not stuck) and no vacuum leaks
If it doesn't drop then you have an air leak, or a stuck throttle plate or a stuck IAC Valve
Adding Fuel doesn't increase RPMs, AIR DOES, that's the point of having a "throttle plate" on a gasoline engine
(Diesel engines use fuel to increase RPMs, this is not a diesel)
As you open the throttle plate and let in more air RPMs go up, THEN more fuel is added by the computer
If you add more fuel at idle you will get an increase in RPMs and then engine will struggle and stall as it "floods out"
thank you for your help. I got the fuel issue resolved, now just fighting the iac valve issues. I unplug the valve and no change in idle. I am throwing a code for it now, P0511.
What resolved the fuel issue?
P0511 means IAC Valve "circuit" has a problem, which would come up if you unplugged the "circuit"/connector
I assume the code came up after unplugging the IAC Valve not before?
Warm engine RPMs should be 650(manual), 750(automatic)
Computer uses IAC Valve to set the idle RPMs
When unplugged the IAC Valve should close and RPMs are then set by throttle plate which is usually set at 500-550rpm range, barely running engine
If idle didn't drop you may have a vacuum leak, so computer can't set a lower idle
But that should also set a code, computer has these codes
P0506 Idle Control System RPM Lower Than Expected
P0507 Idle Control System RPM Higher Than Expected
So if idle was higher then P0507, but no code, so could be computer wants the idle higher, but.............it should still have dropped if computer lost control, i.e. you unplugged IAC Valve
P0511 means IAC Valve "circuit" has a problem, which would come up if you unplugged the "circuit"/connector
I assume the code came up after unplugging the IAC Valve not before?
Warm engine RPMs should be 650(manual), 750(automatic)
Computer uses IAC Valve to set the idle RPMs
When unplugged the IAC Valve should close and RPMs are then set by throttle plate which is usually set at 500-550rpm range, barely running engine
If idle didn't drop you may have a vacuum leak, so computer can't set a lower idle
But that should also set a code, computer has these codes
P0506 Idle Control System RPM Lower Than Expected
P0507 Idle Control System RPM Higher Than Expected
So if idle was higher then P0507, but no code, so could be computer wants the idle higher, but.............it should still have dropped if computer lost control, i.e. you unplugged IAC Valve
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From: Camden ar
What resolved the fuel issue?
P0511 means IAC Valve "circuit" has a problem, which would come up if you unplugged the "circuit"/connector
I assume the code came up after unplugging the IAC Valve not before?
Warm engine RPMs should be 650(manual), 750(automatic)
Computer uses IAC Valve to set the idle RPMs
When unplugged the IAC Valve should close and RPMs are then set by throttle plate which is usually set at 500-550rpm range, barely running engine
If idle didn't drop you may have a vacuum leak, so computer can't set a lower idle
But that should also set a code, computer has these codes
P0506 Idle Control System RPM Lower Than Expected
P0507 Idle Control System RPM Higher Than Expected
So if idle was higher then P0507, but no code, so could be computer wants the idle higher, but.............it should still have dropped if computer lost control, i.e. you unplugged IAC Valve
P0511 means IAC Valve "circuit" has a problem, which would come up if you unplugged the "circuit"/connector
I assume the code came up after unplugging the IAC Valve not before?
Warm engine RPMs should be 650(manual), 750(automatic)
Computer uses IAC Valve to set the idle RPMs
When unplugged the IAC Valve should close and RPMs are then set by throttle plate which is usually set at 500-550rpm range, barely running engine
If idle didn't drop you may have a vacuum leak, so computer can't set a lower idle
But that should also set a code, computer has these codes
P0506 Idle Control System RPM Lower Than Expected
P0507 Idle Control System RPM Higher Than Expected
So if idle was higher then P0507, but no code, so could be computer wants the idle higher, but.............it should still have dropped if computer lost control, i.e. you unplugged IAC Valve
Remove the Air Tube from the intake, move it out of the way so Fan blades can't hit it
Unplug IAC Valve
Have a piece of thicker cardboard or similar flat piece of material that is stiff and can cover the throttle body opening
Start engine
At this time, just to be sure, try to manually close the throttle, a bad throttle spring can allow throttle plate to be sucked open when engine is running, causing higher RPMs
If tha'st not it
Move cardboard in place to slowly cut off air flow into the throttle body opening
That WILL bring the RPMs down
But it should also start causing any air leak to make a lot more noise
Engine, of course, should stall when throttle body opening is completely covered, if not then BIG AIR LEAK
Unplug IAC Valve
Have a piece of thicker cardboard or similar flat piece of material that is stiff and can cover the throttle body opening
Start engine
At this time, just to be sure, try to manually close the throttle, a bad throttle spring can allow throttle plate to be sucked open when engine is running, causing higher RPMs
If tha'st not it
Move cardboard in place to slowly cut off air flow into the throttle body opening
That WILL bring the RPMs down
But it should also start causing any air leak to make a lot more noise
Engine, of course, should stall when throttle body opening is completely covered, if not then BIG AIR LEAK
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From: Camden ar
Remove the Air Tube from the intake, move it out of the way so Fan blades can't hit it
Unplug IAC Valve
Have a piece of thicker cardboard or similar flat piece of material that is stiff and can cover the throttle body opening
Start engine
At this time, just to be sure, try to manually close the throttle, a bad throttle spring can allow throttle plate to be sucked open when engine is running, causing higher RPMs
If tha'st not it
Move cardboard in place to slowly cut off air flow into the throttle body opening
That WILL bring the RPMs down
But it should also start causing any air leak to make a lot more noise
Engine, of course, should stall when throttle body opening is completely covered, if not then BIG AIR LEAK
Unplug IAC Valve
Have a piece of thicker cardboard or similar flat piece of material that is stiff and can cover the throttle body opening
Start engine
At this time, just to be sure, try to manually close the throttle, a bad throttle spring can allow throttle plate to be sucked open when engine is running, causing higher RPMs
If tha'st not it
Move cardboard in place to slowly cut off air flow into the throttle body opening
That WILL bring the RPMs down
But it should also start causing any air leak to make a lot more noise
Engine, of course, should stall when throttle body opening is completely covered, if not then BIG AIR LEAK
the hood was off of this truck... outside in the weather since 2017. I know there is a vaccum line
going to the booster. The master cylinder reservoir has been disintegrated by the sun. Is that even possible to have a leak there? I'm about to give up and take it to a shop. Also, this truck will not run unless the air tube from the air cleaner to throttle body is on.
Plug the Booster hose port at the intake end, if you think that hose is bad
Take air cleaner out, use the cardboard, or gloved hand over air intake into MAF sensor
On the Air Tube is a Breather hose unhook it at either end and plug it, its just part of PCV system, but will suck in air from valve covers/oil pan
Take air cleaner out, use the cardboard, or gloved hand over air intake into MAF sensor
On the Air Tube is a Breather hose unhook it at either end and plug it, its just part of PCV system, but will suck in air from valve covers/oil pan
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From: Camden ar
Plug the Booster hose port at the intake end, if you think that hose is bad
Take air cleaner out, use the cardboard, or gloved hand over air intake into MAF sensor
On the Air Tube is a Breather hose unhook it at either end and plug it, its just part of PCV system, but will suck in air from valve covers/oil pan
Take air cleaner out, use the cardboard, or gloved hand over air intake into MAF sensor
On the Air Tube is a Breather hose unhook it at either end and plug it, its just part of PCV system, but will suck in air from valve covers/oil pan
Hey RonD, I figured I would update this post, I have figured out a few things.
The over fueling issues was an issue with the connector on bank 2 O2 sensor.
The one wire connector I was questioning goes to my oil pressure sending unit.
The 3Krpm idle issue was due to having 2 hoses backwards. (PCV valve hose, and the air cleaner hose were wrong) ignorant mistake but in my defense I didn't get to remove the old engine as it was already removed for me.
As far as the high idle is concerned it's mostly fixed. It's still a little high. Around 1500 rpm's is as low as it will go. Until I plug the IAC valve, then it idles around 6-700. What would be my next move?
Good work on the repairs 
Do you have an OBD2 reader?
Bluetooth OBD2 readers are under $15 online, they use a smartphone as the display, APPs are free or $5
With an OBD2 reader you can see what the Computer sees from all the sensors
Works on ANY vehicle sold in the US/Canada, from 1996 and up, that was required by Law, not an option for car makers, so good tool to have in the drawer
Reason why, in this case, is that the Computer is setting the 1,500rpm for some reason
When you unplug the IAC Valve, you take away the Computer's control of the idle RPMs, and RPMs drop to 600-700, so no vacuum leaks
Computer should also set a code for "higher that expected RPMs" if there was a problem with IAC Valve or its circuit
So the 1,500rpms is "on purpose", based on something the computer "sees" from sensors
If computer thinks coolant temp is under 50degF it will set a high idle to warm up the engine faster, but that idle will go down as coolant warms up, but its not doing that
Could be computer is "insane" as well, lol
Do you have an OBD2 reader?
Bluetooth OBD2 readers are under $15 online, they use a smartphone as the display, APPs are free or $5
With an OBD2 reader you can see what the Computer sees from all the sensors
Works on ANY vehicle sold in the US/Canada, from 1996 and up, that was required by Law, not an option for car makers, so good tool to have in the drawer
Reason why, in this case, is that the Computer is setting the 1,500rpm for some reason
When you unplug the IAC Valve, you take away the Computer's control of the idle RPMs, and RPMs drop to 600-700, so no vacuum leaks
Computer should also set a code for "higher that expected RPMs" if there was a problem with IAC Valve or its circuit
So the 1,500rpms is "on purpose", based on something the computer "sees" from sensors
If computer thinks coolant temp is under 50degF it will set a high idle to warm up the engine faster, but that idle will go down as coolant warms up, but its not doing that
Could be computer is "insane" as well, lol
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Nsherlock
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Apr 25, 2021 02:23 PM
