Lean at WOT???
2000 GMC Sierra ext. cab 4X4. 6" lift with 35" tires. Dynatech SupermaXX long tube headers, hi flow cats and Y, and Gibson cat back. Crane 212/218-.531 lift cam installed a year ago. Cold air intake. Tuned ECU from Nelson. Truck is running crappy at WOT. Feels like plugged cats. As soon as you let up 1/4 throttle it takes off like a bat outta hell. Would not idle right so I opened the set screw a couple of turns. Seemed to help for a while, now is dying again when turning at idle. I bought a wideband O2 and at idle and cruise it reads good. 14.0-14.9. The problem is at WOT. It went to 19+ !!!. I have emailed Nelson and he said to check fuel pressure. At idle I have 53. I just borrowed a fuel pressure gage with a long hose to check at WOT. What should I read? The fuel filter was changed about 20,000 ago. Truck has 86,000 on it. Is the fuel pump the main suspect here? Nelson said he increased my fuel tables aroun 25% across the board. Could this have taxed the factory pump? If so, what is a good drop in replacement that won't break the bank? Sorry for all of the questions, just looking for a little guidance. If it wasn't 5 degrees here I would have checked the WOT fuel pressure already!!
Rubie
Last edited by iowackers; 12-08-2010 at 04:42 PM.
2006 GMC Sierra 1500 HD Crew Cab 4X4, 6.0L, 12" CST lift, 37" tires, CAI. Vinci cam 210*/218* LIFT .587 / .595 LSA 114*4A, Power Slot rotors all around with ceramic pads, Rebuilt 4L80E with shift kit and billet converter.
Rubie
Reply With Quote