I accidentally posted this same problem on the 2007 + board, but hopefully will get some answers here.
Our '99 Tahoe, which had the engine replaced about 3-4 years ago, about 60,000 miles or so, is starting to give us problems starting. Starts right up in the cool mornings, but after sitting in the hot sun all day when I'm at work, it cranks over, acts like it starts, then dies immediately. 2nd try starts right up, but I think there's a hesitation just before the engine 'catches' and it keeps running. Took it to a shop and they said it needed a tune up-figured it could use one anyway, so we replaced plugs, wires, rotor and cap. That did not solve the problem. Thought it might be the ECT sensor or the ignition module. Replaced both, didn't help, still did the same thing. Now, we'd replaced the entire fuel pump assembly earlier this spring as the old one had died, so the fuel pump is running, and the pressure is holding well, doesn't drop. No codes are being shown, and we put our scan tool on it, which can read codes but it can't delve into the complications like an expensive machine might. All it says is that there are no errors. We had replaced the MAF about a couple years ago too. Seems like it always starts up on the 2nd try, but when it's warm outside, or it's been running and then shut off, the 1st start always makes it die. The idle control looked ok, we took it out and it wasn't broken, and anyway, the truck runs fine, no hesitation, no jerking, no stalling. Nice and smooth idling, the tach doesn't jump around. Anybody hear of this problem before? We've tried to think of everything it could be, but can't figure this one out. Please help if you can. Thanks!
Our '99 Tahoe, which had the engine replaced about 3-4 years ago, about 60,000 miles or so, is starting to give us problems starting. Starts right up in the cool mornings, but after sitting in the hot sun all day when I'm at work, it cranks over, acts like it starts, then dies immediately. 2nd try starts right up, but I think there's a hesitation just before the engine 'catches' and it keeps running. Took it to a shop and they said it needed a tune up-figured it could use one anyway, so we replaced plugs, wires, rotor and cap. That did not solve the problem. Thought it might be the ECT sensor or the ignition module. Replaced both, didn't help, still did the same thing. Now, we'd replaced the entire fuel pump assembly earlier this spring as the old one had died, so the fuel pump is running, and the pressure is holding well, doesn't drop. No codes are being shown, and we put our scan tool on it, which can read codes but it can't delve into the complications like an expensive machine might. All it says is that there are no errors. We had replaced the MAF about a couple years ago too. Seems like it always starts up on the 2nd try, but when it's warm outside, or it's been running and then shut off, the 1st start always makes it die. The idle control looked ok, we took it out and it wasn't broken, and anyway, the truck runs fine, no hesitation, no jerking, no stalling. Nice and smooth idling, the tach doesn't jump around. Anybody hear of this problem before? We've tried to think of everything it could be, but can't figure this one out. Please help if you can. Thanks!
