I recently purchased a '99 GPGT Sedan. It ran fine for a few months, and then I had a coolant leak... which I fixed (Block seal, can't beat it).
Well, as soon as the leak was fixed, almost simultaneously, the car began hesitating. When I'd go half throttle or more the car hesitates/bucks. I get a Service Engine Soon light also.
The Codes tell me it's a cylinder misfire. I can clear the code, and I can drive with less than 1/2 throttle... but, as soon as I go past 1/2 throttle it hesitates/bucks and the Service Engine Soon light comes back on. I changed the plugs and wires immediately, but no change. If it's not getting fuel, then it makes sense for the sensors to report a misfire.
Again, previous to thinking it was a fuel problem I did the following:
I changed the plugs and wires immediately, but no change. I went with better than OEM, from what Autozones computer said.
So, thinking it's a fuel problem I did the following:
Checked Fuel Pressure at the Fuel Rail=> Result, 27psi, BAD!
Changed the Fuel Filter => No change
Checked all the fuel lines => No Kinks, all good
Changed the Fuel Pump => No change
Took a look at the Fuel Pressure Regulator => Looks good, no leaks
Sniffed around for leaks => I don't smell anything, and I should know, it definitely smelled when I change the fuel pump
Cleaned the MAF (why not) => No change
Unplugged the MAF (why not) => No change
The 1/2 throttle situation is actually getting worse, I can't go past 1/4 throttle now.
WHAT THE HECK IS GOING ON!
Any ideas???
Other problems I'm having:
1. ABS/TCS light on. I checked and cleaned the ABS harness connectors at the front hubs, but no change. Any other ideas, or threads to read up on that you recommend? I'm ready to just pull the cluster bulbs and say the heck with it.
2. I need taillights, mine are so bad I had to dremel the outer lens and remove, but left the vertical lines. Not bad, but looks kinda silly up close, and you can play it like guitar strings. Anyone have some for cheap?
3. Heater Core is bypassed. Any suggestions on getting one? Should I get one new at the autoparts store, does someone have one in good condition, or should I pick one up at the salvage yard?
4. I recently put 20Kmiles on it over the past 6mo, has 178Kmiles, any recommendations? I'll likely do the LIM gaskets, and contemplating the HV3, but I might fab one up myself, $200 is retarded. Maybe I'll get a HUGE batch made and throw them up on ebay at a reduced price. I can't believe no one has made an alternative product.
Side Note: The car was a DEA repo, so there are A LOT of gutted out items (seats, doors, trunk, etc), it's silly but I've been filling the car back up. The seats literally have all the stuffing ripped out of them, the doors have no window regulators, just a stick in each door to hold the window up; and the trunk has no spare/tools/jack. So far, I've redone the front windows and the trunk, but the rear seat is pretty bad along with the rear windows.
PS. I paid $1500 for it, when it had 158Kmiles, the engine has lettering on it showing it had been recently replaced (it says "Good" "A"), and the transmissions shifts like butter. The engine leaks a bit of oil, and some coolant from the LIM gaskets. The transmission has no leaks. Rear shocks are blown, I replaced the front upper strut mounts, and I replaced the tie rod ends. Was it a good deal? I think so. Perfect Exterior but faded a bit, perfect interior except for the gutted sections. I thought it was a piece at first, but I'm really enjoying it.
Originally Posted by Bob Padilla
