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2000 COROLLA HAS LEAN CODES & MISFIRE CODES

Car has very low power. Fuel pressure is 48psi; I did smoke test no leaks, pulled injectors, check for fuel spark look to be fine. Remove converter, no change. We did a compression test, 190 on all cylinders...

Thanks for any help

what are the codes? Fuel trims? running compression? Is it actually mis-firing? Correct type plugs/fresh? Valve cover tube seals leaking on boots? Fuel contam? Freeze frame data can be usefull.

I don't know if this is a chain drive without looking but it sounds like a couple of teeth have jumped if it's belt driven.

That was my first thought, however, it has a chain

When the scanner is hooked up look at the timing. The knock sensor can be retarding the timing. I've seen knock sensors where the bolt has oxidized and cracked the sensor causing a retarded timing. This won't necessarily throw a code because the sensor is doing it's job and as far as i know there isn't a way the P.C.M. can cross check. If in fact it's the sensor and there is oxidation, if the bolt has to be ruined don't use an off the shelf bolt or one in the infamous "bucket of bolts". This is a collared bolt and a designed tight fit. Unplugging it and driving it will not tell you anything. You'll just throw it into "LIMP" and it will run just like it is now and you may wrongly feel it's not the sensor. Diagnose it by watching the scanner. If you're not to sure what is going on watch the timing and tap the sensor. It should retard within a second. If it doesn't and is reading 20 degrees retarded replace it. Unplugging it will not give you what you think it will.


Another thing i see once and a while is people adding magic additive causing issues. Some of this stuff suggests adding a cap full per gallon and i've seen idiots that think more is better and add the whole quarts to 5 gallons of gas.