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ryan87gn
03-15-2007, 07:15 PM
Ok guys, need some help. Made the following changes to my '87 GN.

-009 injectors from CoryMC - on this site and turbobuick.com
-adjustable fuel pressure regulator - Red Armstrong
-TurboTweak chip from Eric

Current setup is a mostly stock '87.

-XP Fuel Pump
-Fuel Enhancer
-SMC Alky Kit
-Ram air

Probably something I forgot, but stock turbo & motor. Car ran great prior to the adjustments. It's been stored all winter, started here and there. When I start it, it runs for 30 seconds to a minute (fairly smooth) then dies out. When I start it again, the rpms will rev to 1800+, then drop down to 600-800 and die out. Happens each time after that. Eric's sent me new chip, so I know its not the chip. I've got the fuel pressure dialed in to 43, vacuum line off. Seems to be a bit of water coming out of the pipes and the dump pipe, but I figure that's because its been sitting. Any suggestions on where to start? Really need help! Thanks.

Overboost
03-15-2007, 07:34 PM
are you getting any sort of check engine light? has the spark module been changed from stock. these can cause all sorts of havoc that takes you days to find. check the IAC motor and be sure it is not froze with any type of water that has gotten in there and makes it flake out.
run a scan tool if you have it and see if you notice anything "strange" as it is running (tps voltage out of whack, O2 reading shooting up)
or, try some sea foam, it fixes just about anything.

Keller
03-15-2007, 07:37 PM
Possibilities:

- Fuel pump relay
- Pump
- Intermittent connection in wiring

In theory, while the car is running, the oil pressure switch should cover for a bad relay because there is a failsafe wired in. Does this still work with the 'hot wire' kits? Should.

Nothing would help a bad pump or intermittent wiring. I've never really heard of the wiring being bad (just weak).

I have had a similar situation to this. Headed to the track. Go to line up. Car won't restart in the lanes. Get pushed to the pits. Try to figure the thing out for an hour. AAA card in hand, I'm ready to call for a tow and decided to crank once more...*VROOM!* I go make two quick passes before they shut down the track for the night. I pack up...and its dead again. Do everything including beat on the tank and it starts running. Drive it home, and it dies at least once more along the way. Replaced the stock relay and XP pump - no more problems.

Incidentally, plugging in the wire to force the pump on (as in to drain the tank) had no effect when it was down.

Be interested in hearing what fixes this.

http://www.gnttype.org/forums/showthread.php?t=6310

ryan87gn
03-15-2007, 08:19 PM
are you getting any sort of check engine light? has the spark module been changed from stock. these can cause all sorts of havoc that takes you days to find. check the IAC motor and be sure it is not froze with any type of water that has gotten in there and makes it flake out.
run a scan tool if you have it and see if you notice anything "strange" as it is running (tps voltage out of whack, O2 reading shooting up)
or, try some sea foam, it fixes just about anything.

No check engine light. No, no change to the spark module. Car is stored indoors, generally the only water it sees is when its washed. Didn't see anything abnormal on the scan tool.

ryan87gn
03-15-2007, 08:22 PM
Possibilities:

- Fuel pump relay
- Pump
- Intermittent connection in wiring

In theory, while the car is running, the oil pressure switch should cover for a bad relay because there is a failsafe wired in. Does this still work with the 'hot wire' kits? Should.

Nothing would help a bad pump or intermittent wiring. I've never really heard of the wiring being bad (just weak).

I have had a similar situation to this. Headed to the track. Go to line up. Car won't restart in the lanes. Get pushed to the pits. Try to figure the thing out for an hour. AAA card in hand, I'm ready to call for a tow and decided to crank once more...*VROOM!* I go make two quick passes before they shut down the track for the night. I pack up...and its dead again. Do everything including beat on the tank and it starts running. Drive it home, and it dies at least once more along the way. Replaced the stock relay and XP pump - no more problems.

Incidentally, plugging in the wire to force the pump on (as in to drain the tank) had no effect when it was down.

Be interested in hearing what fixes this.

http://www.gnttype.org/forums/showthread.php?t=6310

I checked the fuel pump connection. I'll check it again. You know, I generally do hear the pump running when the car is running. I'll have to go listen for that again as well. I'll keep you updated...

Thanks to both for the advice!

ryan87gn
03-16-2007, 12:29 PM
Update: Fuel pump seems to be fine, can definitely hear it running. Dropped a note to CoryMC, who I had got the injectors from. Now, it seems, he bought them from someone else who supposedly bought them from FullThrottleSpeed. Gave Eric from TurboTweak the #'s on the injectors as he's tried helping me out (especially to determine its not the chip). He said one of the injector part #'s was old.

Overboost
03-16-2007, 08:18 PM
keller, what is an "XP pump"?

Keller
03-16-2007, 10:50 PM
Red Armstrong's (Quad Air) tested/modded Walbro pump.

ryan87gn
03-17-2007, 10:03 PM
What should my O2 voltage, TPS, IAC, LV8 and MAF be when the car is NOT warmed up? I was able to get some readings today and wanted to see if they mean anything from a cold car. I've looked at the quick reference chart and I believe it is for a warm car. Thanks.