Mechanics

GT

2000 Toyota Celica • 4 cylinder FWD Manual • 124,000 miles

I have a 2000 toyota celica gt and I am having what feels like an ignition misfire. It misfires below 3000 rpm and runs better above 3000 rpm still having a slight misfire. I have changed the ignition coils and have changed spark plugs. It has coil over plugs and I cant not figure out what is wrong. Its throwing a random misfire code and a pending cylinder 3 misfire code. I had a clogged cataylic converter then I replaced that then started getting this issue.
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Orioles2005
April 10, 2011.



Yes it has a cel light on its throwing a p0300 and a pending p0303 code and thats it.

Tiny
Orioles2005
Apr 10, 2011.
It does run better when I first start it up. When it was cold out it had a hard time starting and once it warms up the idle drops real low and starts to idle rough.

Tiny
Orioles2005
Apr 10, 2011.
Buy a can of carburetor and choke cleaner and start the engine. Spray all of the vacuum lines and listen to the engine for it to stumble or rev higher. The spray where the intake meets the head and the throttle body. The first part sounds like a vacuum leak.

With a multimeter, check the voltage at the coil for #3.

Check the cold start valve or injector for proper operation. When cold, the engine needs a little more fuel than normal for starting and to warm up properly.

Next, perform a compression test. You should see in the area of 150 PSI from each cylinder and no more than 10 PSI variance from cylinder to cylinder. If #3 gives you a significantly lower reading, squirt a small amount of oil in it and check again. If no change, bad valve(s)(not so bad), if compression rises, bad rings(not so good).

Rivermikerat
Jun 13, 2011.
Try changing ur air filter and cleaning your mass air flow sensor. Does it feel like a miss fire? Or does ur check engine light say "random miss fire"

Tiny
Spirit7799
Mar 2, 2012.
Closing thread due to lack of response and age of thread.

Rivermikerat
Mar 12, 2012.