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I set up vrg3's scantool (amazing, really sweet. Had to use the previous version, newest hangs when it looks up rom id). I was thinking I had engine problems, but the more I look at it, the less I think so. Here's my thread in the engine forum: http://bbs.legacycentral.org/viewtopic.php?t=27559

To sum it up, my engine wont run right when it's warm. After it hits 203F, the fan kicks on and I get trouble. It like misses or something. Here's what I've tried so far:
New NGK plugs
wires
coilpack
coolant temp sensor
about 1 can of seafoam total through my IAC valve
white plug knock sensor
grounding mod

still problems, this is what the scantool told me when I was having these problems:

idle- 700rpm
sys. voltage- 13.76v
timing- 20 degrees BTDC
airflow- .78 to .82
load- 38 to 40
TPS- 4.64v
injector pulse- 2.048ms
IAC- 32-33 at idle, 37 to 38 at 2k rpm
O2- .02 to .99
fuel trim- 0 to 2.3
barometric pressure- 729.15

I've tried running with the O2, and pressure sensor disconnected.
I have no idea what else to try. Help?

Turns out my timing belt was the culprit. It had skipped a few teeth and threw me off. It was interesting because with the scantool hooked up, the timing never changed from 20 degrees, warm or not it was constant. Now, with a new belt and the cams lined up like they should be the timing rises when I hit the gas.

The cam sensor must not kick in until the car hits temp. Before that it must default to 20 degrees. When the sensor kicked in, the timing was way off and it caused it to miss, and without a proper reading, my timing probably didn't change. Glad it works now, I'm gonna put my PDA in my car with Pocket DOS to run the scantool while I drive, it'll look sweet!

your timing should stay at 15BTDC if turbo, 20BTDC if non - give or take two degrees.

the ECU doesn't use a map, but an internal calculation (so I'm told) of what the timing should be when you rev the engine or put it under a specified load - looking at the 'timing correction' field tells you how far it's having to deviate from that preset calculation to avoid knock or improve economy (when cruising)

timing should change when you rev the engine, always

and acceptable values for me anyway is anything between 10BTDC and 45BTDC - I see 45 on a regular basis when cruising in the city, and normally 30 to 35 when on a heavy load.

oh, what I was going to say was:
the cam sensor is operational regardless of the engine temperature, what was most likely happening is that because of the added or reduced timing physically (with the belt) the ECU was seeing an abnormally low or abnormally high O2 reading and it was trying to adjust timing as well as fuel to correct it at idle.

what would explain why it happens after the fan kicks off when you rev the engine could be the fact that once you bring the unloaded engine up to a certian rpm, it will run rich there for a moment, and when the O2 readings settle back down then the ECU will try to do the same compensation, screwing with your timing because it's seeing an invalid reading.

Hm, interesting! Thanks for the education.

Now, with the O2 sensor, it defaults to .30 when unplugged and stays there. When I ran the car without the O2 sensor, I still had the exact same issues.

I think the weirdest change was that after the new belt, the tiiming changed from it's constant 20 degree reading and actually would rise with engine rpm's

n2x4 wrote:I'm gonna put my PDA in my car with Pocket DOS to run the scantool while I drive, it'll look sweet!

If you can get this to work I'm interest to know how you did it. I have a sony Clie that I have no use for and this could be a good use for it...