running rough on 3 cylinders

2001 TOYOTA RAV4
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EGAZ11
Engine Performance problem 4 cyl Two Wheel Drive Automatic 160000 miles

One morning i started my car and it was running on 3 cylinders- rough idle, poor acceleration, hesitating when giving gas. I replaced all the plugs and found a fouled plug in #3 but no improvement in power or idle. The check engine light code read misfire on #3 cyl. I have put two bottles of Lucas fuel injector cleaner in two full tanks and no help. Its not running hot and sometimes runs ok at higher speeds. Coil ? f injectors? cat converter? plug wires? What can i do?
Apr 28, 2010 at 4:26 PM
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RASMATAZ
  • ✓ASE Certified Mechanic
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Yep first check to see if the #3 coil is working here is a guide to help you confirm.

https://www.2carpros.com/articles/how-to-test-an-ignition-system

If it has spark lets check compression and then fuel injector operation here is a guide that will help you walk down the problems using easy tests.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Please let us know what you find. We are interested to see what it is.

Cheers

Apr 28, 2010 at 5:13 PM
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EGAZ11
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Yep it was low compression my mechanic said it has a burnt exhaust valve and will cost 800.00 to fix. I will need to park it for while. Thanks for the help the guides are great.
Apr 29, 2010 at 5:03 PM
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