It was time to replace the timing belt on my 1998 Ranger 2.5 4 cyl. it was running rough and back firing. when the harmonic balancer was removed the aluminum sprocket on the back had some teeth that had broken off. A used balancer was purchased the timing belt was replaced. Engine still runs rough and engine code " camshaft sensor". Long story short: crankshaft sensor, camshaft sensor,another balancer (guaranteed to be correct),and ecm were replaced with no improvements. I re-checked all the timing marks they are spot on. Any ideas?

 

What was the code number(s) you had before, and what is it now?

Rough running and backfiring is usually a mechanical problem not sensors or computer.
Possible causes are:
Vacuum leak
Clogged exhaust(first symptom is loss of power at highway speeds)
Leaking or partially blocked fuel injectors
Failing coil packs
Leaking valves(valve train issues)
Water in the fuel, often called "bad gas", lol, and you can get a tank full any time and any where.

A slipped/stretched timing belt causes loss of power but engine still runs fine as far as no misfires or stumbling.

The broken teeth on the CKP sensor ring should have set a code, the computer is not that smart but missing CKP sensor pulses should have caused it to notify you.

Have you looked at the spark plug tips to see what they tell you about engines running condition, i.e. lean or rich or oil burning
How many miles on the engine?
Has the MPG fallen off since the problem started?

Is it possible for you to do a compression test?



The CKP sensor(crank) is the main sensor, if it isn't working engine won't start.

CPS(cam) is a sub sensor, it allows for better sequential fuel injector timing and better spark advance timing, but fuel injected engines did and can still run just fine without these, they were added for better MPG and lower emissions.

A quick test you can do is the Clear Flooded Engine test:
Turn key on
Press gas pedal to the floor and hold it down
Crank engine

Engine should NOT fire or try to start, fuel injectors are shut off but spark is on
If it fires then you have fuel leaking in, usually from a fuel injector.

As soon as you release gas pedal fuel injectors will start up again

 

P0340 camshaft sensor circuit malfunction. Code was cleared and came back up. Does the #1 spark plug need to be removed to align the crankshaft marks? Is it possible that the marks are aligned to the exhaust TDC vs the compression TDC?

 

TDC, top dead center, just means the #1 piston is at the top of it's stroke, there is no compression or exhaust stroke as far as the Crank Shaft is concerned.

Compression stroke and exhaust stroke are decided by the Cam Shaft.

A cam shaft gear is always twice the size as the crank gear, if a crank gear has 20 teeth it's cam gear will have 40 teeth, so 2:1 ratio

TDC is just to tell you #1 is at the top, you then set the Cam to it's mark that coincides with #1 at TDC

 

All of my timing marks are lined up, I am going to put it back together, but before I do that I am going to examine the camshaft sensor wire carefully to see that it is not shorting out anywhere. This wire harness runs underneath the air compressor bracket and is a tight fit.
I did check the continuity of these wires back to the ECM it was good, but it can still be shorted out and have continuity if it's not completely cut through. Once back together I will start it up and check to see what codes come up. Now that I'm sure that the timing belt is correctly installed I can focus on other areas. I will post these results. Thanks for your help.

 

While had the ac compressor bracket removed I noticed that the cam shaft position sensor harness was routed under the bracket instead around the bracket and it looked like it may have been pinched under the bracket. I taped it up with electrical tape and re routed it behind the bracket. Used a harmonic balancer install tool to insatall the harmonic balacer.
Put it back it all together and started it up, it went to an idle right away and ran with no back fire or stumbling. I still have an ECL on but have not had time to check the code. I will check the code maybe tomorrow if it's not raining or snowing.

 

Good work

If CEL came on right away, then it is most likely an unplugged sensor.
Or EVAP vacuum line is off.
Computer tests all the sensors on startup but doesn't use most until engine warms up.

Cold idle should be above 1,000 rpms then it should slowly drop to "target rpm" when engine warms up, so in about 5 to 8 minutes.
Automatics target is 800
Manual 700

After warm up CEL is usually a problem with actual engine operation, i.e. lean/rich, EGR, misfires.

 

It is running a lot better, but the CEL P0340 code came back on. Is it possible that this has something to do with the ECM programming codes? Not sure what to do next.

 

P0340 can be a tough one because it may not be a Cam sensor(CPS) issue at all.

The crankshaft(CKP) sensor is the big kahuna, most important, engine won't start without it pulsing at #1 TDC.
And that is what the Cam sensor is compared to, the CKP sensor.
So if there is a misalignment on the CKP, you will get p0340 because Cam sensor doesn't 'agree' with CKP, CKP is the boss sensor, even if it is wrong, lol.
So P0340 could be misaligned CKP sensor

Also a few sensors share the reference wire for the CPS, the Grey/red stripe wire.
TPS
ECT
IAT
O2s
DPFE

Any short in one of these wires could show up as P0340
This is pin 91 on the computer

 

Is there an alignment procedure for installing the crank shaft sensor?

 

There is a tool for it

Many never use it and don't have any issues, so not sure that's it, just making the point that CPS code can be cause by other things, not just CPS