Mysterious lean condition
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Mysterious lean condition
After driving this car for the last couple weeks without so much as a hiccup, I left home for work the other day and noticed it was running uncomfortably lean. (especially considering how pig rich it was before) I got home, stuck my head under the hood and noticed the distinct sound of air being sucked in from somewhere it's not supposed to. Found a cracked hose, replaced it, noise gone. Took it for a test drive... still lean.
I started wondering if I could even trust the narrowband af gauge, so I hopped out to sniff the exhaust. Smells rotten, stings the eyes, no fuel smell... definately very lean.
Walbro pump and fuel filter are practically new. I can hear it working just fine. Double checked basically every rubber hose, silcon connector, etc.. I've got nothin. The only other things Ive really been able to think of is dirty injectors or the MAF sensor itself. I suppose its possible that when I took everything apart, some dust got in there or possibly the connectors rubbed on something dirty in the engine bay. I plan to pick up some MAF and electronics cleaner this afternoon to see if I can take care of the problem.
Any other suggestions you guys might have? Something Im missing? If cleaning the MAF doesnt change anything I might have to find a place with a smoke machine, but really really dont want to spend money on that. Im on a ramen and burrito budget and want to have this car track ready this summer!
I started wondering if I could even trust the narrowband af gauge, so I hopped out to sniff the exhaust. Smells rotten, stings the eyes, no fuel smell... definately very lean.
Walbro pump and fuel filter are practically new. I can hear it working just fine. Double checked basically every rubber hose, silcon connector, etc.. I've got nothin. The only other things Ive really been able to think of is dirty injectors or the MAF sensor itself. I suppose its possible that when I took everything apart, some dust got in there or possibly the connectors rubbed on something dirty in the engine bay. I plan to pick up some MAF and electronics cleaner this afternoon to see if I can take care of the problem.
Any other suggestions you guys might have? Something Im missing? If cleaning the MAF doesnt change anything I might have to find a place with a smoke machine, but really really dont want to spend money on that. Im on a ramen and burrito budget and want to have this car track ready this summer!
#3
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Gotta feed my need for speed, even if my stomach pays the price! Such is the life of a college student...
Alright its a 88 Turbo, custom intake with kn air filter, racing beat exhaust, primary cats gone, ac and ps removed, rtec ecu and walbro 255lph fuel pump all set up for a bigger turbo, but was switched to OE turbo and manifold before I bought it (hence why it was so rich before, and why its so peculiar that its running this lean), stock injectors, block of plates... I dunno, it has some other stuff but nothing that is pertinent to the issue at hand....
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Alright with the AFM out to clean I noticed that the flapper door seems to be sliiightly crooked so that air could seep thru the top. I am wondering if the door is not moving as much as it should because the air can more easily just move around it, so its not injecting enough fuel. Any thoughts?
Ill try and post pictures later today
Ill try and post pictures later today
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