ROUGH & HESITATION

2001 Toyota Corolla

Tiny

CCross

June, 10, 2012 AT 4:16 PM

2001 Corolla - rough idle on initial start up in the morning, then clears up, then hesitates slightly on accelleration from a dead stop after that.

I've changed coil packs, spark plugs, MAF & O2 (upstream) sensors, & added a fuel injector cleaner.

Still have idle & hesitation problems - help!

FOUND 2911 RELATED QUESTIONS

5 Answers

Tiny

ASEMaster6371

June, 10, 2012 AT 4:21 PM

I think you are on the right track with injectors. You need them professionally clean, not by an additive. Clean the throttle body as well.

Another issue with toyotas was carbon build up on the intake valves. A top engine cleaner done by a shop can be done to see if it helps. In a lot of cases, removal of the head and a valve job was the answer as carbon absorbs fuel cold and after it warms up, it will run ok.

Get a shop to verify this for you.

Roy

Tiny

KHLow2008

June, 10, 2012 AT 6:25 PM

Any trouble codes?

Tiny

CCross

June, 10, 2012 AT 6:45 PM

P0300.

And it "consumes" oil (no leaks that I could find).

Thanks for the help!

Tiny

KHLow2008

June, 10, 2012 AT 6:55 PM

Multiple misfires. Check the engine compression and valve clearances apart from what Roy had recommended.

Oil consumption would often create a lot of carbon deposits if the intake valve seals are bad.

Tiny

CCross

June, 10, 2012 AT 7:54 PM

Will do - thanks again!

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