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So I got this car for $100, and I don't know exactly the differences between the 92 and 94 I have but this is what was happening.

The TPS broke and the guy couldn't figure it out, he said it kept loosing power and he would push down the pedal and nothing would happen. So he parked it because it wouldn't start one day. Two years later, I got it, unplugged the TPS and it worked. So I just kinda slapped a new used tps in there. Seemed to work good without adjustment.

So, I tried to drive it down to Costco on the 2 yr old gas, and it made it ok, was guttless, and so I blamed the gas. Got down, and it started dieing. It died driving away, and going down the hill out of costco. I finally made it back and it seemed powerless. So I bought feeler gauges, adjusted the TPS to factory specs, adjusted idle, and thought it was good to go.

Well today I took it for a test drive, and it was still just powerless, so I tried to adjust the timing, and the distributor was turned completely advanced, and that seemed the only way to keep it running. But, I set it to the factory 10 degrees advanced, let it idle for like 5 mins, and it died. Tried to restart, no dice. So Finally after waiting for 5 mins, it started, very poorly, barely running! Advanced the timing, and then noticed every time I step on the brake the RPMs drop way low, and the car almost dies. So I went through and checked for vac leaks, none.

So here I am open for ideas. I am thinking possibly:

Dirty injectors
Bad Distributor
Bad Coolant Sensor (Seems to only do it when it is warm... maybe)
Vac Leak Still
bad brake booster
Something Electrical!!!

So if anyone has any thoughts, the ECU still blinks code 12 for the TPS... So I have tried to reset the ECU, but still won't! I am so flustered!

Maybe you just need a new TPS?

SuperK wrote:Maybe you just need a new TPS?

Yeah, but that wouldn't explain why it runs the same even with the tps unplugged....

bad catalytic converter? Plugging the exhaust?

No, tried that already... and the neighbor would be pissed even more if I tried it again. So Far he has come over and complained 2 times, both ending in he is going to call the cops. No cops yet...

But here is an update:

Replace Fuel Filter, ran a ton of lucas through the fuel system... nothing. Unplugged IAC, and didn't help. Unpluged TPS, and didn't help. I have broken down the symptoms though, it will only die when warm. And When I had the IAC unplugged I was able to test drive it, but it still had no power!! I also ran a ton of seafoam cleaner through the intake and nothing....

Try the MAF sensor on the intake, it controls how much fuel is injected into each cylinder.
Pull the #1 spark plug and have a look at it to see if its uber lean or uber rich. Rich would
be black carbon buildup, lean would be white.

Test the MAF sensor with a multimeter as per the online manual on the site. I dont remember
offhand what the values should be but I had one for sale that I know works if thats the problem.
They are hundreds new. Ive also got a 94 throttle body, injectors and distributor.

Nice neighbors... If your not breaking any noise laws or whatnot then just ignore them.


If its not the MAF check the timing, could be way retarded.

Oh also the 94 B6 has two cats, one
right under the header and the main one further down. My main one went out before the coffee can sized
one under the header did. Think it was 50 bucks to weld in a straight pipe.

I was talking with a mechanic friend and he said he bets it is the coffee can one under the header. I pulled it off before the main one.... But I guess I am just going to be cutting them both out. Well punching out the small one and recycling the other. Stay tuned for what happens!!

u my 95 dohc did this exact same thing. i still never figured it out and its still parked. if you do find out let me know. i tried replacing the Maf as well and didnt change much. start with the basics, get the battery tested to make sure that car is getting enough power to run everything correctly. and go from there

Well guys this is what I have done. I thought it was the cat, and it still might, but when I parked it for the last time, the top coolant hose burst, so I replaced it, and now the thing won't start. It is being weird. The things I did:

replaced coolant hose
Put a different VAF on
took EGR pipe off of Exhaust (To vent for cat clog)
hooked up intake "correctly" (Made hole in coupler for IAC)

And then bam, it won't start. Here is the funny thing, So I can smell gas, so I know I don't need gas. So then I check for spark, and there is spark... but when I pulled the plugs they are soaked with gas. So while starting it I reach into the back and unplug the pump, it starts wanting to start so I plug it back in and nothing... I did this a couple times with no luck, so I am thinking weak spark. So I go and get the extra distributor I have, put that on, and notice the cap and rotor are a little bad, so $30 I have new ones, and I slap them in. Go to start it and.... same thing. Then I check the plugs, all of them, and their gap is like .055+. So I put them at .040~.038. Somewhere around there. I am turbo, so I know you can go smaller and they run fine. And I think stock is like .042??? And then, nothing. It wants to start a little bit more now when I unplug the fuel pump, but as soon as I throw that thing back on, it seems like INSTANT FLOODING!!! I would think it was maybe a bad injector, but all of the cylinders are like that..

So I need some help... This $100 car is now a $300 car, and it still doesn't run.

Oh and other things I have replaced now are:
Battery
Radiator and Hoses
PCV
Fuel Filter
TPS

0.039 - 0.043 inches gap stock sparkies

Whats your O2 sensor up to during all this, something is making it run
hella rich if its flooding. VAF might need adjusting.


When you say you took the EGR pipe off the exhaust - whatcha mean?
like is there a hole that is allowing outside air into the exhaust in and
around where the O2 sensor is?

You dont want to open it up there, thats worse than having a clogged kitty cat.

Get the little spark plug tester from autozone, with the adjustable screw... see what the intensity of the spark is.


Is it throwing the TPS code with the other TPS? What code is it throwing now?

If the car is getting fuel, and enough spark... it could be your ECU. My friend's MX-3 has great spark, great fuel, all new parts, and the VAF/MAF works... but the ECU went ka-plut and it don't start.

If its a regular 94 B6 DOHC ECU I have an extra:


http://www.mx-3.com/phpBB3/viewtopic.php?f=2&t=66333

I cleared the TPS code, and it hasn't come back.

I replaced the ECU today, and same, thing. So I pulled the injectors and, they are FILTHY!!! I think they need to be cleaned, and or just replaced. So since I can't get another set until next week, I might try cleaning them.

if a filthy injector is causing that much headache, send them to somewhere like witchhunterperformance to get them professionally cleaned and rebuilt. I doubt it's something you can clean without the right tools, and they'll flow-test them before and after to make sure you are getting the correct flow.

Well, finally had time to install the injectors... still floods. So we are gonna just gut the cat and see what happens!

Anyone else has any ideas??? When we floor it while trying to start it, it almost starts, but not....???