Racetronix. Little to no fuel pressure
12-01-2010, 04:12 PM
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Racetronix. Little to no fuel pressure The shop just recently installed a fresh forged LQ4 motor and put a break in tune on it. I drove it around a bit yesterday and everything seemed fine. Ever since the car will crank but wont fire. I immediately thought of a bad crank sensor but when I checked my fuel pressure gauge and when I turn the key to the on position it only reads no more than 3psi. FP was fine driving around last night. Any ideas?
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12-04-2010, 03:29 PM
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ok so really no fuel pressure at all. I swapped fuel pump fuses and nothing. so either something is clogged up, something not getting electrical connection, or fuel pump gone bad. just changing the filter probably won't fix it... thinking I should get a little pressure if it were a clogged filter... anyone else agree?
12-04-2010, 03:32 PM
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oh one other thing... to test the fuel pump, I should be able to unhook the fuel filter from the fuel line and turn the ignition on and I should have fuel coming out if the fuel pump is working properly correct?
12-05-2010, 09:20 PM
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check the hose from the pump to the housing. i had good pressure one day, came out to fire the car up for a buddy the next day, itd fire up, but wouldnt rev. finally got to where itd bearly start. i pinched off the return line, still no psi, when i pulled the pump the rubber hose had ruptured.
12-05-2010, 10:05 PM
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k. figured I'll need to look into the fuel pump. but got to decide whether to drop a 98' tank or cut a hole. have to replace hatch shocks before I could get back there though. did racetronix supply you with another hose or will a gm replacement do?
12-06-2010, 03:14 PM
#12
The Racetronix kit comes with the proper corrugated hose.
I would not use a kit with a rubber hose in the tank... they tend to be short lived.
Also the 98's tend to have some regulator issues, so check this out first before you start buying parts.
If interested, I'll be glad to set you up with a pump kit for your car.
I would not use a kit with a rubber hose in the tank... they tend to be short lived.
Also the 98's tend to have some regulator issues, so check this out first before you start buying parts.
If interested, I'll be glad to set you up with a pump kit for your car.
12-06-2010, 11:51 PM
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The Racetronix kit comes with the proper corrugated hose.
I would not use a kit with a rubber hose in the tank... they tend to be short lived.
Also the 98's tend to have some regulator issues, so check this out first before you start buying parts.
If interested, I'll be glad to set you up with a pump kit for your car.
I would not use a kit with a rubber hose in the tank... they tend to be short lived.
Also the 98's tend to have some regulator issues, so check this out first before you start buying parts.
If interested, I'll be glad to set you up with a pump kit for your car.
12-08-2010, 04:55 PM
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update...
new fuel filter + charged battery = nothing. I still don't think my fuel pump is getting power (can't hear it running, all I hear is a "click" that comes from that direction, maybe its because all my other noises in the cabin when I turn the key over).
new fuel filter + charged battery = nothing. I still don't think my fuel pump is getting power (can't hear it running, all I hear is a "click" that comes from that direction, maybe its because all my other noises in the cabin when I turn the key over).
12-19-2010, 12:50 AM
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update...
My buddy and I cut a trap door tonight. Checked the voltage at the connector on top the fuel pump and got 5 volts with the key in run position. Noticed the plug states its a 5 volt connection? Odd, cause we were thinking it'd need 12v. Anyways, the pump wont turn on. So we pulled the fuel pump and couldnt figure out how to get that yellow plug looking deal from the harness on top out therefore I had to leave it in the car. Now what to do??? I'd hate to order a new pump if there's a way for it or something in the assembly causing the problem...
My buddy and I cut a trap door tonight. Checked the voltage at the connector on top the fuel pump and got 5 volts with the key in run position. Noticed the plug states its a 5 volt connection? Odd, cause we were thinking it'd need 12v. Anyways, the pump wont turn on. So we pulled the fuel pump and couldnt figure out how to get that yellow plug looking deal from the harness on top out therefore I had to leave it in the car. Now what to do??? I'd hate to order a new pump if there's a way for it or something in the assembly causing the problem...
12-19-2010, 09:40 AM
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12-19-2010, 02:42 PM
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Ok so I hear there is a place on the pcm that I can run a wire from it to the battery to get 12v to the fuel pump. Where is this connection thing or is it not on ls1 cars?
