Hello! I have a 1998 4.0ohv 4wd. Recently I got the p1309 code and also the p0171,p074 bank 1 and 2 lean codes. I proceed to change out the Cam Position Sensor and syncro. I did them both correctly exactly by the book. Made sure to put the engine at top dead center ect. I reset the computer ( left battery unhooked for few hours ) and started her right up. It began to relearn itself but started running rough and sputtery. I maybe thought it could be the
TPS ( throttle position sensor )
MAF ( Mass air flow )
IAC ( idle air control )
and air temp gauge.

I ordered a new MAF and TPS since i found a good deal on amazon. I clean the temp gauge and IAC. After another reset it developed this problem.

from 0mph full throttle no acceleration at all. 0. half throttle was quick and fast and sounded healthy. I proceeded to do some research on the fourms and found a issue could be ground wires and PCM ( power control module ,the ecu/computer ) I checked all my grounds and even took off my coil pack and cleaned the grounds under the coil pack and threw it back on. I even checked the fuel filter and got sprayed right in the ear even though i relived the pressure! Right now its doing another computer reset.

My question to you dear kind folks is this. What the hell could it possibility be!?

ive checked spark plugs, cleaned air filter, checked fuel filter, checked all vacuum lines, brand new MAF,TPS, cleaned IAC and temp gauge. I need help please! Im lost and dont know what to do. thank you all so much!

 

check all battery connections to and from battery to engine / engine to body firewall / body to frame / frame to battery ( frame to battery and battery to engine are the 1st to fail )

also maybe the computer circuits are failing ,

 

Sounds like you've addressed all the sensors but haven't found the real problem that you started off with. Maybe the fuel injectors or fuel pressure regulator right off the top of my head .

 

@ Cheese_man do you have or know of a wiring diagram? I want to double check that all of them are coorect. and @ Ranger_fan14 any way to test fuel pressure regulator? Because in park revs up fine, in netural revs up, half throttle is quick but full sputters.

 

there is a connector on the fuel rail that looks like a tire valve

this valve is for pressurized injector cleaning , that is where you connect a pressure tester

pressure at idle should be constant , a slight dip when you accelerate but returns to normal pressure

if you have been using 87 octane with ethanol , then is probably certain little chunks of rubber have dislodged from inside of the rubber fuel lines and are clogging the fuel injectors

those older rubber hoses are NOT ethanol tolerate , ethanol just eats that older rubber for lunch

some of the newer injector cleaner formulations dissolve older rubber inside the injectors thus cleaning them out .

 

Ill take a look! And yes have just been using 87 ill run fuel injector cleaner through there as well

 

make sure that you use the pressurized injector cleaners that connect to the fuel rail

regular in the fuel tank injector cleaner are too diluted to quickly clean clogged injectors

 

On ranger station a fourm user told me I possibily installed the syncro wrong if the old one was installed wrong. So im going to redo the install also heres this morning test drive update.

Just got back from test drive, let it run in the driveway for a few minutes then went for a drive. Ran around for 5 minutes normal without flooring it or anything. I then went half throttle , accelerates smooth,clean healthy sounding a little slower then expected but i am on 33s and 410 so didnt expect it do be quick. did a 0 to 30/45ish half throttle and took video did fine. Did 0- ? full throttle wont even budge! Starts mis firing,back firing, popping, low low rpm's about to die. Has 0 power. Anything full throttle under 30mph does this, any speed more then 30 full wide open has power.Moves quick no sputtering. Occasionally when i stop and put it in park or neutral i rev it, and itll sometimes start random mis firing, sputtering ect, but then itll go back to normal and rev fine. I got a video of this happening as well. Any idea on what this issue could be!? Ive changed all the sensors correctly, cleaned the pcm memory, cleaned all connections, checked battery connections as well. Could it be a bad coil pack? Or maybe cats?

 

sputtering is from lack of fuel , so partially clogged injectors sounds like the culprit.

but also FULL acceleration 0 effect , may also be clogged catalytic converters

i was reading a lot of other people suffering clogged CATS from using 87 octane fuel with ethanol

1 last thing is , 1 person ultimately had to replace his fuel pump because the ethanol has disintegrated the pick screen so much that the pieces were plugging up the fuel pump pickup tube

 

Ill take off the exahust this week on my day off and take off the fuel rail and check injectors, I took a video of what its doing, Its just weird because its only doing it from 0-30 anything faster then 30 wide open throttle its fine. Also when in park ill floor it, no problem runs and revs fine ill do it again and itll start to sputter then go away.

 

How about fuel pressure. Had the same and fuel pump pressure was low. There was enough fuel at low speeds but not high. Also a EGR valve not working right will cause rough idling.

 

If your fuel pressure regulator is located on top of the engine like mine is one test you can do is disconnect the vacuum line from it and check it for the presence of gasoline but if raw gas were leaking into your intake it would most likely make it very hard to start the engine ie long cranking time and then rough running when it does start till the excess gas is burned in the cylinders.

From all you've said I don't think it's the regulator but I'd still get a gauge and check the fuel pressure.

Also the fact that over 30mph it runs fine doesn't sound to me like an exhaust issue. I've had catalytic converters go bad and every time I just had almost no power at all, like sticking a potato in your exhaust pipe. I could barely get up to 30mph much less go faster. Of course you could have an obstruction that moves out of the way as the pressure in the system builds with speed so removing the exhaust and checking that would tell the tale there.

If you don't have a fuel pressure tester I think Autozone will loan those out.

I"m also wondering if you maybe have a crack in your distributor cap or something wrong in that area, bad rotor maybe?

Are you pulling any codes now that you've replaced all those sensors?

 

No codes but the thing is, the truck ran fine before just slowish and gutless but way fastet then what it is now, but at 0 i could do wide open and take off. I think i didnt correctly install the syncro. Its probably out of time.

 

You may have to get the slowish and gutless back before going ahead with fixing it. Like I suggested, check the fuel delivery flow and pressure before throwing money at it in parts.
Remove the injectors and do a spay test if pressure and flow rate are OK.

 

I would definitely suggest you go back and redo everything you've done regarding the cam position sensor and syncro and check the timing before doing anything else. Make sure everything is installed correctly and if possible test the sensors to make sure they'e ok. It's not unusual to get a brand new sensor that fails or is bad to start with.

Found this on Youtube, see if it helps

 

With a distributor the engine must be not just be at TDC but must also be on the compression stroke and not be between the exhaust/intake stroke. Maybe it is OK for sensor. I would rotate the engine to the compression stroke just to be on the safe side.
Also if the oil pump is not lined up you can turn the pump with a long screw driver down the hole.

 

I followed that video but rather then set my engine to TDC i used the old syncro as a refernce. I dont have any p1309 code anymore. Just lean codes.

 

Are those codes cylinder specific? If it is just a cylinder or two it would indficate plugged injectors. If it is over engine I would suspect main fuel delivery. Pump or regulator??
Possibly clogged inlet filter to pump in the tank.

 

lets not get ahead of ourselves

you should perform a fuel rail pressure test before anything else!!!!!

this will reveal if the injectors are indeed nearly clogged up or if it is a fuel pump pressure problem

 

I will! But idk how that can be a problem. Because all it ran sorta fine before but not mis fires like crazy

 

I don't really know how that would work, if the first install was off slightly then it would seem to me you'd need to start from scratch with the new synchro and make sure it's installed correctly. As the video points out it's a very precise setting, just a little off and your engine won't run right.

Any way though, how's it run now?

 

Both banks lean indicates low fuel flow. There may be plenty for low load conditions but not enough at higher loads. If pressure and flow is good then maybe injectors clogged some.