linuxrunner

Reading the voltage between vf1 and battery ground is showing 5v. from what i can tell this indicates that the computer at least thinks i am running very rich.

It does smell like raw gas from the exhaust.

Since i had the injectors cleaned and rebuilt 20k mi ago i started testing elsewhere.

Tested VF1 with T1/E1 jumpered to test o2 sensor, using an analog multimeter it was oscillating about 9 times ever 10 sec. that looked good.

Used 4crawlers instructions to test AFM and everything tested out right on.

Tested coolant temp sensor, 500 ohm at operating temp which looks to be right on.

Removed cold start injector wiring no change in richness (i realize this won't test for a leaking injector)

That was everything i could think of tonight, what else should i test?

Eventually i will need to test the injectors for leakage anybody know if that can be done without pulling the intake?

Just realized 2 more easy tests i can do right now, spark plug wire resistance and make sure the air filter is not clogged.

linuxrunner

okay, air filter is dirty but not clogged. I'll pick a new one up tomorrow.

Highest Resistance on the plug wires is 5k ohm on the longest wire, so that looks good.

Cap and rotor are about 20k mi old, but i clean the contacts up about 5k mi ago.

dromomaniac

I'll have to think on this, but I'm really posting because "linuxrunner" from Oregon!

I'm just a newish hobbyist with regards linux [most of my learning coding time is spent on random BS to keep things running at work (hydrogeology lab) which never seems to end and which is both awesome and futile]. And I miss Oregon, so much...the parts not clogged with sanctimony, anyway

Well, you have tested everything I would have suggested except the vacuum lines. I have a 3.0, so I'm accustomed to fretting about these. Not sure how crazy and H.R. Giger-esque it is in the 22re.

linuxrunner

I realized that i did the static test for the AFM, but forgot to finish testing by moving the vain while watching resistance.

I may have found something, there are 4 spots between fully closed and fully open that i can consistently get to to to infinite resistance.

pulling the cover of the AFM you can see deeply worn groves in the resistive strip.

Playing with the wheel in the AFM i can advance it to change the vf1 value from 5v down to 2.5v. This may just be tricking the ECM to go lean, but i would guess that the breaks in the strip are definitely causing drive-ability issues so looks like i will be picking up a new AFM tomorrow too.

Will update with any difference made.

RJR

I'm pretty sure it's the other way. +5 volts indicates the computer thinks the mixture is lean, and is trying to enrich it. If the voltage is all the way to 5V, it says the computer has run out of range to enrich it further.

It's likely that the ECU is getting bad data from the O2 sensor, making it think the engine is lean when it's actually not. That causes the ECU to needlessly enrich the mixture, giving you the rich mixture you're seeing.

You might need to consider replacing the O2 sensor, and/or carefully inspect the wiring.

linuxrunner

That actually makes more sense, because it was pinging pretty bad.

However I did test the o2 sensor using the method from the FSM and can see a nice oscillation i have had bad o2 sensors before and they have always failed this test. Is there a different way you would suggest to test it?

linuxrunner

Since i plain on purchasing a new denso AFM anyway does anybody know if the supra AFM bolt on to the stock 22re airbox or do you have to use a new cone filter?

They are close to the same price so i figure if it's a bolt on affair, why not?

linuxrunner

Couldn't find anybody who had a new OEM Denso AFM for an 82 supra available around here.

So i ended up getting the normal 22re version.

I did a resistance test on the new one before i put it in. No bad spots when you sweep the vain. also the new one starts out at about 140 ohm and sweeps up to around 780 ohm. The old unit started at infinant and jumped wildly to a max of 500 ohm.

hooked up new AFM and checked VF1 port, at idle it hangs out just under 3v give it some gas and it jumps around a bit. I had just plugged the ECM fuse back in so i'll measure it again after the computer has a chance to learn a bit.

Drive test is good, previously i had all my power in the first 1/4 of the accelerator peddle. half way down and WOT gave me exactly the same amount of power. Now i can feel response through the whole sweep of the accelerator peddle.

Also noticed that before when i gave it or let off the gas it would lurch badly that is MUCH improved.

I will drive it around a bit more (since the ECM reset the idle had not decided if it wants to be at 600 or 800) and see if it smooths out any better.