2000 Corolla p0300

[00corolla]

Let me start off by saying any help would be great.

My wifes Car, a 2000 Corolla LE. About a month ago she was on the freeway when the timing chain gave out. After pulling the engine apart and replacing valves and timing chain, we put the engine together but now we are getting a p0300 code and when the engine is cold it runs like crap (The breaks also don't work very well when the engine is cold but work fine when it warms up). We have changed plugs, Changed and gaped all Valve Lifters, Changed all gaskets. We are basically at a loss.

Does anybody have any suggestions, also is there a way to test coil packs? I assume toyota can but will charge me an arm and leg.

[fishexpo101]

Quick way to test for a defective coil pack is to cycle out the packs with a spare coil until the problem goes away - not very convenient though.

You already changed the plugs - so that's good, eliminates one potential culprit. Make sure they are gapped to 0.044". Most of the Iridium plugs come pregapped, but always a good idea to double check them. Other potential culprits with a P0300 (random misfire):

- Faulty coil pack
- Faulty O2 sensor
- Faulty fuel injector
- Faulty camshaft position sensor
- Faulty wiring (broken or short to ground)
- Burned exhaust valve or valve seat
- Clogged catalytic converter
- Faulty PCM

[MacktasticSlick]

Ok, I've got a silly question... What do you mean when you guys are talking about gapping your plugs? It's not really important right now to me because my car runs great, but I was just curious.

[fishexpo101]

Gapping a plug - usually entails taking a feeler gauge or sparkplug gapper and verifing the "gap" between the ground electrode and the center electrode.

Example image -

[MacktasticSlick]

Ah. Thanks. So... what do you do for a living? It seems like you practically invented the car. I've read some of your wall o' texts, and you sound pretty damn smart.