Q: Rough Idle / difficult start

asked by on December 12, 2016

My car started off with having a rough idle. It's now having issues starting. Check engine light was on and had the code read. The code was for the camshaft position sensor. Replaced that along with the purge solenoid. Changed the ignition coils and there is no change. We originally thought it was the timing chain but, when we took everything apart, we discovered that the timing chain was not loose and the gears were aligned properly from TDC. The gauges are also sporadic now and the car almost sounds like a diesel when we do get it to start. Any help or suggestions are appreciated. I can do the mechanical work on my own.

My car has 119000 miles.
My car has a manual transmission.

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A rough idle may be caused by many different things such as low fuel pressure, low voltage to the fuel injectors, dirty fuel injectors, a vacuum leak, a faulty Oxygen sensor or a dirty or failing idle air control valve. Any of these possibilities relate to fuel delivery issues that will disrupt the normally balanced air/fuel mixture that would otherwise allow the motor to run smoothly. I would recommend having an expert from YourMechanic cometo your location to diagnose your rough idle problem.

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