New in-tank pump problems for 04 GTO
10-30-2006, 10:04 AM
#1
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New in-tank pump problems for 04 GTO Over the weekend i helped my friend install a walbro 255lph in tank fuel pump in his 2004 GTO. The install didn't seem to bad @ first. We got it in, everything plugged up, moodded the bucket as per another thread here. The car just wouldn't start for nothing. We could hear the pump running and had pressure at the rail. He started messing with the tune in his predator handheld programer and started messing with the injector slope. The only thing there that seemed to help was taking the slope all the way to the left (-40%). The car would start fine, idle fine. When we raised the rpm's it would run lean, then basicly fall flat on its face @ WOT. 
Any ideas? The car is a 2004 GTO, LS1, M6, has a K&N intake, Pacesetter LT's, cats, Borla mufflers, !AIR, !EGR, predator tune, and will be running 100-125 shot through an NX MAF wet kit (was doing the pump as a precaution).
Any advice would be greatly appreciated! Thanks in advance!
Any ideas? The car is a 2004 GTO, LS1, M6, has a K&N intake, Pacesetter LT's, cats, Borla mufflers, !AIR, !EGR, predator tune, and will be running 100-125 shot through an NX MAF wet kit (was doing the pump as a precaution).
Any advice would be greatly appreciated! Thanks in advance!
10-31-2006, 06:51 PM
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have you chacked the pressure at the rails while modulating the throttle? did you remember to put the oring on top of the new pump nipple before reinstalling it into the tank? i found that strapping the pump tight into the nipple acceptor with zipties kept the pump from losing pressure under heavy load... good for 650rwhp with 55lb injectors!
10-31-2006, 07:19 PM
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We didn't check pressure at the rail with a gauge, but it shot out a good 6-7 feet from the front of the car... We do need to put o-rings on the nipple. He called the shop where he bought the pump and they told him he needs 2 o-rings on the nipple? The zip tie thing is a good idea. I think we are going to work on it again tomorrow. Did you modify your bucket or the lid ( the part the pump slides into)? If so how? Thanks!
11-01-2006, 10:52 AM
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Whenever I install the pumps only part modified is the part around the pump. I leave the bottom of the bucket alone. I have found that if you modifiy the bottom, you run into issues on long WOT runs.
Chad
Chad
11-02-2006, 09:00 AM
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We got the pump all the way in last night. Seems to be working the way it should now. Car started right up, idle fine, and kept pressure up @ WOT. Thanks everyone for your replies!
