My camry just recently started running really rough anytime it idles or is going slow. The issue goes away once I get it driving fast enough. But if I’m going slow or idling it sounds like a diesel. The check engine light came on too. We tried replacing the spark plugs but that didn’t do anything. It also feels a lot less snappy, and takes longer to speed up. Any ideas? Could it be the ignition coil?
It could be, but the check engine light is trying to give you the system with the fault. Get the code(s) read and find out.
I’ll go do that it doesnt have the light on now but it does come on randomly too but that’s always been an 02 sensor because my car got stolen 2 year ago and the fried a wire to one so it shorts out… but I will go see if it throws a code.
Beyond having the code run I’d suggest a compression check. One cylinder may have poor compression, which would cause rough idling that would smooth out at speed.
These engines are known for loosening cylinder head bolts. Check the rear side of the engine on the passenger side and see if there is any sign of coolant leak. Otherwise, I agree with reading the codes, there is your hint (and ours!).
Try to pull the codes. This will give you ideas on where to start.
Your best bet is to get an OBD 2 scan. This way if its a short in the AF sensor or O2 sensor it will read eratic.
The Throttle position should be 0 percent or 1,2. 5 and above replace the throttle body.
“If” you had an engine over heating issue just before this problem, then be concerned about the head bolts coming loose, and blowing the gasket, and hopefully not warped.
Check every vacuum line including the one that goes from the bottom of the throttle body along the bottom back side of the engine. Its just a vacuum reservoir. Yes jack it up and crawl under.
I just bought an 03 camry and ran the gauntlet on diagnosis. Mine idles under 700 rpm kinda rough, and the throttle percentage is at 16.5 at idle
Throttle body’s worn out, which isn’t unusual for these.