QuestionQUESTION: I consider myself a DIYer. However, my fiancee's car recently stalled in a desolate intersection after dark. With none of us having time to work on it and it being cold and late, the decision was to tow it to the dealer.. so I ask you this for my own well being and to have knowledge for when they call to state what is wrong / cost.
The car was acting fine until, like I said, it stalled at an intersection (at a stop). The codes read P0016 and P0340. Now, 4 months ago, the car was riding rough, wouldn't respond at times and threw a P0340. I replaced the camshaft sensor and it went away. Never did it have problems starting. Do you think this is related?
Also, I have an ongoing, intermittent P0441 which I'm thinking of having them look at. I believe this is likely unrelated.
Do you have any advice?
Its a 2.4l 4cyl with 83k miles. I have a bad feeling its the timing belt, but I have no idea if it has a belt or chain...
ANSWER: Hi JC,
Your conjecture about the timing belt is a definite possibility in light of the 0340 and the 0016. An inspection by removing the upper timing belt cover (2 screws) will tell you that instantly. I note that the 0340 would occur if the cam shaft stopped turning and the 0016 says that there is an inconsistency between the crank sensor (which would be normal even if the belt broke) and the cam sensor signals (which if no longer turning would certainly cause such an inconsistency). The 83k miles seems early for the timing belt to break, but it could nonetheless have broken. The piston/valve situation is free-wheeling, but inter-valve interference can occur if the cam shafts are turned independently. So the chances are good, if the belt broke at idle, that there is no internal damage to contend with. So you should have an easy time to check out that theory by going to the dealer yourself and having a look.
Roland
PS Please 'rate' my answer, and where you see the question about 'volunteer of the month' please consider a 'yes' answer. Thank you
---------- FOLLOW-UP ----------
QUESTION: Two more questions if you don't mind..
1 - Do you think the timing belt is most likely at this point (just trying to mentally prepare :) )
2 - Would a timing belt that is ready to break, exhibit any symptoms?
Thanks again
ANSWER: It is a possibility but not a certainty. Likely for sure, but it could be the cam sensor or its magnet also, so cross your fingers.
I am not aware of any specific symptoms prior to breakage except perhaps some reduced perfomance due to slight shift in the timing between the crank and the cam due to mechanical changes in length as it possibly stretched before breaking.
Roland
---------- FOLLOW-UP ----------
QUESTION: Well, its confirmed. The timing belt went. They recommended doing the water pump as well, plus the car needs a new battery (so they say). I never replaced it, the car was running off battery while we were trying to start it w/ hazard flashers on plus it sat for a couple of cold nights.
They say the tally will be about $1300. However, the mechanic I spoke to say he believed it was in fact an interference engine and wasn't sure yet if there was more damage... Is this possible?
AnswerHi JC,
The manual says:
"The engine is freewheeling meaning it has provisions for piston-to-valve clearance. However valve-to-valve interference can occur if the camshafts are rotated independently."
The best way to check out whether the latter possibility occured would be to observe now whether the timing marks on the camshaft sprockets are equally displaced, rotation-wise, from their normal tdc position which is a 3 and 9 o'clock. If so, then it would appear to me that no valve-to-valve interference occured when the belt broke. Of course it will be necessary for the mechanic to not turn the camshafts independently of one another when installing the new timing belt.
Roland
PS Please take a moment to 'rate' my answer. and where you see the question about 'volunteer of the month' please conside a 'yes' answer. Thank you JC.
