fuel pump and injector trouble

[hydell3gst]

I bought a 95 gst the other day it didnt run when i bought it it has a starter issue but i tried pull starting it and found it wasnt getting gas, the fuel pump wasnt coming on i couldnt find any relay or fuse so i just rewired it and went on about my way but the fuel injectors are not spraying gas gets to them, i ran direct power to one and it sprayed full blast no problem i ran a volt check on the plug and there all 4 at a steady 7.48-50v, i know they should be at 12v i just cant figure out why there not spraying and i have an adjustable fuel p reg and it is always on 0psi when i turn the pump on it jumps to like 50psi but it goes right back to zero when i turn it off i know that it shouldnt do that is that a bad regulator or what??? i gotta figure all this out i wanna be able to drive my new car.

thank you.

 

[And_44]

If I was on my PC I'd share the link for a no start. But do a search for "no start" and there is a tech post written with a check list you can go through.

 

[Chaosweaver]

Check the 20A motor fuse in the engine bay, make sure its not blown. Also, the fuel pump relay is under the dash, right next to the ECU. You have no take off the passenger side panel to get to it.

Does the pressure fall to 0 right away? Or does it take like 10-15 mins? Usually some AFPRs will bleed out to 0 after a while.

 

[jpmxrider489]

How about your resistor pack for the injectors?

 

[hydell3gst]

it will fall to zero as soon as the pump goes off and i ended up finding the relay and it was good

and the resistor pack is pluged in but i dont know anything else about it

 

[Chaosweaver]

The FPR has to have a huge leak to do that.

 

[NHerron]

How did you 'rewire' the pump?

Do you have spark? If no spark, no pump, no injectors I would blame the CAS.

Also, when you cycle the key to 'run' does the check engine light come on for 5 seconds and then go off?

 

[hydell3gst]

im gonna replace the fpr today hopefully, and its getting spark as far as i know i pull started it yesterdayand it ran but it ran like shit and wouldnt stay running unless i was pushing the pedel alot, and yes the check engine light is on when you turn the key on

and on the fuel pump i rewired a new fuse into it and ran it to a switch
im new to dsm, whats the CAS?

 

[boost97gst]

CAS= Cam Angle Sensor. That could cause spark but no fuel if im not mistaken. A cps, crank pos. sensor, failing will give you no spark AND no fuel. I doubt your fpr is the issue.

 

[hydell3gst]

i dont think the fpr is the issue either its getting plenty enough fuel pressure, idk im gonna try and have a diagnostics done for the check light and see what it pulls up, it seems weird that sensors that have nothing to do with fuel can affect wether it works or not like i said im new to dsm this is my first one

 

[steve]

i dont think the fpr is the issue either, its getting plenty enough fuel pressure. idk im gonna try and have a diagnostics done for the check light and see what it pulls up. it seems weird that sensors that have nothing to do with fuel can affect wether it works or not.

like i said im new to dsm this is my first one

I doubt the FPR is causing this issue but investigating why the pressure drops to zero so quickly may solve other problems down the road. You can ignore it for now.

Just to be clear, the car didn't run when you got it and hasn't run except when you "pull started it". Exactly how did you pull start it? Did it seem like it was running on all the cylinders or more like a lawnmower.

Please also explain in detail what you've done with your rewiring so we can be sure your not masking some other problem. The factory wiring should be working and since it's not, the underlying problem could be continuing to effect you.

Spelling and punctuation make a huge improvement in readability and understanding that's why the site makes them a requirement. It doesn't matter if your using a phone or a computer when posting the requirement remains. Please see if you can spend a little more time on your posts.

EFI based engines use the computer to control things like spark and fuel. The computer needs information from the sensors like engine timing information from the Crank Angle and Cam Angle sensors (or the single CAS on a 1G), the Air Volume, Air Temp, and Barometric Pressure sensors in the MAS, the Engine Coolant Temp sensor and the Throttle Position sensor to correctly know how much fuel to spray and when to fire the injectors and spark plugs.

NHerron wants you to confirm a simple test, does the ECU turn the CEL on for 5 seconds when you turn the ignition on and then turn the CEL off? That identifies that the ECU turned on and ran correctly for 5 seconds. If the CEL stays on then you might have saved error codes you want to read out or the ECU could have crashed before turning off the CEL.

 

[boost97gst]

I just reread original post. The afpr dropping to zero IMMEDIATELY is odd. Not sure whats going on there. Possibly the fuel pump is draining backwards when powered off. So if your not getting injector pulses grab a book or download the factory service manual and find out what drives inj pulse train. Theres your culprit. These cars are blackholes that accept only money , get ready for it...