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Chevy/GMC Trucks \ 91 fullsize fuel delivery issue.. i think..91 fullsize fuel delivery issue.. i think..
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replies 1
following 2
baggednbad91
+1y
1991 1500 with 5.7 (350) has throttle bodie injection (tbi)
im running a fuel cell with an external pump made by i think airtech or something and it opperates in the psi range for the tbi. however the pump is a pulsating pump and i dont think the stoc in tank pump was.
truck doesnt always crank.. looking at it while spinning over the motor the injectors just trickle some fuel then when it doest crank it idles great but while in gear if you try to get it above 2000 rpms upon acceleration it acts as though its running out of gas and sometimes it quits running and then is difficult to crank afterwards.
new fuel filter, and the pump are brand new.
any help would be great
im running a fuel cell with an external pump made by i think airtech or something and it opperates in the psi range for the tbi. however the pump is a pulsating pump and i dont think the stoc in tank pump was.
truck doesnt always crank.. looking at it while spinning over the motor the injectors just trickle some fuel then when it doest crank it idles great but while in gear if you try to get it above 2000 rpms upon acceleration it acts as though its running out of gas and sometimes it quits running and then is difficult to crank afterwards.
new fuel filter, and the pump are brand new.
any help would be great
bigperm
+1y
hey man... i was having the exact same issue on my 95 tbi. had an inline pump from a fuel cell. went through 2 airtex pumps, changed the filter, rebuilt the tbi itself, changed egr valve, etc... truck started running really rich and sputtering, and sometimes would just die, or wouldn't crank at all, just like you described. fouling plugs, black smoke, all that. turns out that the pump was dumping WAY too much fuel to the tbi, and was overloading the built-in pressure regulator on the TB. hooked it to a psi gauge, and it read like 90 lbs at the throttle body, where these trucks only require 16-20 lbs (i think). it was just too much pressure for the stock tbi regulator to hold. anyway... i ended up taking off the in-line pump. put a factory delphi pump/ sender unit in the top of the fuel cell, and 90% of my problems disappeared. i think what happens is the internal regulator in those airtex pumps wears out quickly, and the pump starts pushing a shitload of pressure, causing the engine to flood out. two solutions:1) try to get a high performance fuel press. regualtor. I know JET products makes one for our trucks. http://shop.ebay.com/?_from=R40&_trksid=p3907.m570.l1313&_nkw=fuel+regulator*+tbi&_sacat=See-All-Categories2) cut a hole in the top of your fuel cell, and drop a factory pump in it. hope this helps!! good luck!!
hey man... i was having the exact same issue on my 95 tbi. had an inline pump from a fuel cell. went through 2 airtex pumps, changed the filter, rebuilt the tbi itself, changed egr valve, etc... truck started running really rich and sputtering, and sometimes would just die, or wouldn't crank at all, just like you described. fouling plugs, black smoke, all that. turns out that the pump was dumping WAY too much fuel to the tbi, and was overloading the built-in pressure regulator on the TB. hooked it to a psi gauge, and it read like 90 lbs at the throttle body, where these trucks only require 16-20 lbs (i think). it was just too much pressure for the stock tbi regulator to hold. anyway... i ended up taking off the in-line pump. put a factory delphi pump/ sender unit in the top of the fuel cell, and 90% of my problems disappeared. i think what happens is the internal regulator in those airtex pumps wears out quickly, and the pump starts pushing a shitload of pressure, causing the engine to flood out. two solutions:1) try to get a high performance fuel press. regualtor. I know JET products makes one for our trucks. http://shop.ebay.com/?_from=R40&_trksid=p3907.m570.l1313&_nkw=fuel+regulator*+tbi&_sacat=See-All-Categories2) cut a hole in the top of your fuel cell, and drop a factory pump in it. hope this helps!! good luck!!
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