Won"t hold fuel pressure?

scotty305 · 09-03-2008, 12:48 AM

I visited phantomworks this weekend and we got a few things figured out.

We used my AEM EMS so we could datalog the cam & crank angle sensors and fire the injectors and coils manually.
Turns out the crank angle sensors were too far away from the trigger wheel for the AEM to be happy with them. (might have been OK for the stock ECU, but the AEM is a bit more picky about signal strength). We used some washers to shim it closer and the EMS was reading both timing inputs and calculating RPM and stat sync'd correctly. The car still didn't fire, so we checked for fuel and spark. Injectors were all clicking but no spark from any of the coils. Eventually tracked that down to the ignitor not being grounded well (it grounds through the case), we cleaned it up and bolted it to the chassis and the car fired up and idled.

Fuel pressure looked OK at idle and increased when blipping the throttle in neutral, but I had to leave before we got a chance to take it around the block and make sure everything was still good during a full-throttle pull.

Just wanted to update the thread in case anyone else comes across a similar problem.

phantomworks · 09-08-2008, 01:44 PM

Still will not hold fuel pressure but while driving the car it seems to be ok but when shut off the car drops immediately to zero PSI.

David Jerome · 09-09-2008, 09:07 AM

Quote:

Originally Posted by phantomworks

Still will not hold fuel pressure but while driving the car it seems to be ok but when shut off the car drops immediately to zero PSI.

After it sits for an hour or so does it smoke on startup and kinda struggle to idle the first few seconds?

phantomworks · 09-09-2008, 01:40 PM

No, it actually idles fine and there is no smoke. It even drives like there is nothing wrong.

My only concern is that it didn't do this before, it used to hold fuel pressure for a day or two before the gauge would reach 0 psi.

09-03-2008, 12:48 AM	#1
scotty305 Rotary Fan in Training Join Date: Mar 2008 Location: Culver City, CA Posts: 84 Rep Power: 18	I visited phantomworks this weekend and we got a few things figured out. We used my AEM EMS so we could datalog the cam & crank angle sensors and fire the injectors and coils manually. Turns out the crank angle sensors were too far away from the trigger wheel for the AEM to be happy with them. (might have been OK for the stock ECU, but the AEM is a bit more picky about signal strength). We used some washers to shim it closer and the EMS was reading both timing inputs and calculating RPM and stat sync'd correctly. The car still didn't fire, so we checked for fuel and spark. Injectors were all clicking but no spark from any of the coils. Eventually tracked that down to the ignitor not being grounded well (it grounds through the case), we cleaned it up and bolted it to the chassis and the car fired up and idled. Fuel pressure looked OK at idle and increased when blipping the throttle in neutral, but I had to leave before we got a chance to take it around the block and make sure everything was still good during a full-throttle pull. Just wanted to update the thread in case anyone else comes across a similar problem. Last edited by scotty305; 09-03-2008 at 12:50 AM.

09-08-2008, 01:44 PM	#2
phantomworks The Newbie Join Date: May 2008 Posts: 21 Rep Power: 0	Still will not hold fuel pressure but while driving the car it seems to be ok but when shut off the car drops immediately to zero PSI.

09-09-2008, 01:40 PM	#4
phantomworks The Newbie Join Date: May 2008 Posts: 21 Rep Power: 0	No, it actually idles fine and there is no smoke. It even drives like there is nothing wrong. My only concern is that it didn't do this before, it used to hold fuel pressure for a day or two before the gauge would reach 0 psi.