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Discussion Starter #1
This is probably a dumb idea but I wanted to see if this may actually work. My car is running super, super rich. I followed the car while someone else drove it and black smoke rolled out almost the entire time. The driver said he never took it past 3k and hardly gave it any gas at all.
I've check the basic stuff, ecu codes, tps sensor voltage, CAS, CTS, new injectors and the FPR. Awhile back I had this problem and it was a cracked exhaust manifold, which caused a little black smoke but no where near what its doing now. The cracked manifold is still on the car because Its kinda my beater and i would rather just bolt a header up when i get some extra money.
The plugs are all gapped correctly and are not fouled with oil or gas, and the car runs and drives just fine.
Basically it looks like a deisel truck when I take off, and full throttle is just rediculous.
Anyways, would tilting the TPS sensor forward trick the ECU into thinking it was at lets say 75% throttle when its actually at 100%?
If so, how will this effect the timing map, and drive ability?
 

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I don't believe tilting the TPS would do anything to solve your problem. The ECU is still going to base it's injection off the load it sees (basically MAF voltage) not the TPS. From my understanding the TPS is used to check for idle, WOT, and quick throttle transients only. It sounds like you have more of an air metering problem. I'd check around your MAF area, the MAF itself, etc. Maybe try swapping in someone else's known good maf. Check MAF voltages per the FSM. Check for vacuum leaks (although that initially causes a lean condition, I've seen the ECU over compensate if the condition is small enough for the engine to run with the leak). I would check these types of things.
 

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Discussion Starter #3
Oh ok, I understand what your saying about the MAF, that makes more sense, lol. Your probably right about the MAF tho, I haven't checked voltage and I don't remember the last time i cleaned it (I live on a gravel road).
I'll check voltages/clean it later and see what I come up with.
Thanks man.
 

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Discussion Starter #5
Lol, yeah that would lean it out. The problem was the cracked manifold (upstream of the o2). Swapped it with a different one and now it runs perfect.
 

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Did you change the O2 sensor?

I didn't see it listed...

Just a thought...
 

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Discussion Starter #7
Yeah I replaced almost all the sensors before I found the cracked manifold. I would have like to put a header on but a free stock manifold is better than a cracked manifold, lol.
So if anyone is running super rich and have checked almost everything, check your exhaust manifold.
 
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