I am trying to help get a vehicle back in working order for my girlfriend. Her Saturn is throwing the P0366 code. It has not sent any check engine lights. We had a dealership friend look and confirm the code.
That being said. The symptoms are vaguely similar to bad spark plugs or transmission issues. It is losing power. Step on the gas and it gets almost no acceleration. The vehicle shutters are specific speeds. Dealership friend did tell us that it IS possible that it was just excessive carbon buildup in the engine. But i don’t know how to confirm that. He mentioned running seafoam through the engine as a carbon cleanup? I could have vehicle oil changed And do a carbon cleanup through an oil change facility as well. I believe it is due for oil anyway.
What I am looking for is some help diagnosing the specific problem and the possible cost of repair. Any help would be greatly appreciated.
So you say a P0366 code but NO check engine light? Then it no longer has the code but it has stored one.
You post '07 Saturn but no mention of mileage. You have dealership friend but no one has offered help in diagnosing the problem or fixing it? The P0366 can be caused by one of more of these problems.
Cam sensor wiring routed too close to spark plug wiring (causing interference)
Poor wiring connection at cam sensor
Poor wiring connection at PCM
Bad cam sensor “B” on bank 1
Damaged reluctor wheel
This is a Bank 1 problem and it can cause lack of power. I’d suggest replacing the bank 1 cam sensor once I’d carefully checked the wiring. The sensor itself is $22. I don’t know if it is difficult to get to or not on this car. Curious that it is not setting a check engine light because it should.
outlook with 3.6 motor sometimes has issues with the timing chain stretching/wearing and throwing codes for crank/cam sensors. a dealer should be aware of driveability issues. if you say my 3.6 seems down on power. they might say something.
I will mention it. My friend was only able to run the codes for me and offer minor suggestions. We have only done it once. We would have to pay for more repairs and stuff if we took it back. Their sho lets them do some minor checks and stuff for “friends and family.”
The camshaft sensor produces 4 pulses per camshaft revolution, which the ECM uses to tell where the camshaft is relative to the crankshaft. The ECM uses that info to fine-tune the ignition and injector timing. It also uses it to verify the variable valve timing is doing what it should. I wouldn’t expect a severe performance hit with this code. In the event this signal disappeared the ECM would probably disable the variable valve timing function, but otherwise the engine should still run pretty good; though possibly you’d notice a little less quickness in the car’s acceleration.
If the cam signal didn’t disappear entirely but instead was corrupted with noise, that might cause the engine to run poorly. And if the camshaft/crankshaft phasing wasn’t correct – for example the timing chain was stretched or skipped a tooth-- that could cause the engine misbehave. Given the symptoms my guess is one of these
the code is a red herring, symptoms unrelated to camshaft sensor, and the problem is elsewhere. Do a basic tune-up procedure, replace spark plugs, engine air filter, engine oil and filter, check idle rpm and ignition timing & check for vacuum leaks.
timing chain is stretched. If you can see something inside the hole that you pour the oil that moves with the camshaft, turn the crankshaft forward and backward manually to see if the crankshaft movement is significantly delayed w/respect to crankshaft. If so, possible loose timing chain.
cam sensor signal is corrupted. The easiest way to check this is with a Saturn scan tool or equivalent. A lab o’scope could be used also.