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Running pig rich and stalls when warm

tweeder

New member
I'm talking diesel rich, the pipes are black and you can visually see it rolling out the pipe with every spike of the throttle. I have seen my fuel trims at -17. Once it's warm it surges and wants to stall. I have replaced the o2, iac, maf and map sensors. I noticed a small header leak at cylinder #2 because the header wrap was getting sooty. It wasn't something that I could feel but I welded it up. The spark plugsan o2 were sooty. MThe idle seems normal. I doubt I have a vacuum leak as its all new hoses. I did spray the engine with carb cleaner ad seafoamed it and didn't turn up anything.
 


vacuum leak would have you run lean,

fix your map

It was running rich before, thats why I changed out all sensors. The maf was because it set a code. For the map, I have one in there now I just need what the operating perimeters are to see if it's correct.
 
Pull and label all six spark plugs to see if they are burning evenly. Any single plug that seems to be burning especially cleanly would indicate a lean condition which could stem from a bad injector, air leak, electrical problem, etc. A plug showing a color that is darker t han KFC Fried Chic ken could indicate an injector that is running colder or more richly..
 


Pull and label all six spark plugs to see if they are burning evenly. Any single plug that seems to be burning especially cleanly would indicate a lean condition which could stem from a bad injector, air leak, electrical problem, etc. A plug showing a color that is darker t han KFC Fried Chic ken could indicate an injector that is running colder or more richly..

All are blacker than Toby's a$$
 
I went out and really doused the upper manifold gasket with two cans of carb cleaner and I seem to have a leak in the manifold next to the thermostat so I have a new gasket ordered and will be in on Wednesday. Anything I should take care of easily as I have the blower off?
 
new vac lines and vac tee's they are gonna break, should have them before you do the work, its 5 bucks worth of piece of mind.
 


We'll I have the new gasket on and it's still leaking from the same area in the upper plenum around the thermostat housing. Now what?
 
your sure everything is clean and free of old gasket?

you can try a thin smear of rtv both sides of the gasket around the outer edge of the gasket. torque it back down let it sit over night to cure, then fire it up.
 
I reseated the intake gasket and I think I got it but I'm still running rich and surging when warm. I made a contraption to pressurize the intake through the throttle body and I was leaking from the map so I took it out and siliconed it and that helped, now it leaked down from 20 or so psi very slowly, I soaped the engine and I didn't' see any. Mabey the purge solenoid? I'm thinking of taking off the throttle body and making a block off plate and then pressurize it from the octopus. I'm just wondering if if possibly be leaking from the brake boost port? I'll have to make a smoke test and see if that shows something
 


negative fuel trims means it is pulling fuel. i would check that you don't have a stuck injector or bad fuel psi reg. test fuel pressure might be too high.
 
negative fuel trims means it is pulling fuel. i would check that you don't have a stuck injector or bad fuel psi reg. test fuel pressure might be too high.

Sorry negative fuel trims mean it's running rich. I have a fuel pressure guage on the rail and it's reading around 43 psi.
 
Not sure if this is it but I sprayed a soapy solution in the injector holes and sure enough injector number three is bubblin, so I have a set of o rings on order.
 
Got the new o rings in and now a new problem, I swear I get a new problem every time in fix something else. Now it won't start, I checked and I am getting fuel and spark but it backfires really powerful and loud. So powerful that it blows the rubber exhaust tubing right off the pipes.
 
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