Engine Problem

[celica2002]

Can anyone help me with an engine problem with my 2002 Celica? The engine makes a popping sound on tick over which can be heard in the induction side and exhaust. The car drives rough at low RPM. I expect the problem is still there higher up the rev range but not noticeable. I have had the engine light on once for misfire on cylinder 3. New coil has had no effect. Erased the light and has not come back although problem persists. I checked for air leaks by spraying carb cleaner around inlet manifold. Did not take any in. Any ideas as it may lead to the financial black hole that is the dealership.

Found the problem..... It wasn't until it started running much worse that I could see it. A cracked insulator on the central electrode on one of the spark plugs. Plugs not been in that long, are those Densos any good?

[Boro Sera]

2002 celi won't be under warranty anymore.......so why go to the dealer?

There are plenty of good independants who charge reasonable prices .

[Ken N]

Might be a valve problem. I think I would give the dealership a miss on this one.

[Black Knight]

Could be quite a lot of things.

Split hose maybe somewhere after the air flow meter? Worth checking they're all connected properly and not split. A damp rag wrapped around them can help with diagnosis with the engine on (it'll suck/blow against the rag). That's the easy one.

After that you're into making sure that all the wiring is connected properly.

It's possibly something in the VVT-i control system keeping the valve timing advanced but I'd have expected a warning light if you got that. If the valve timing is stuck advanced it won't idle smoothly (quite often diagnosed as a misfire)