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Cougar_Marauder
10-12-2017, 09:19 AM
I believe I have a leaky injector. My car stalled on me 2 times now, both times I was sitting at a stop light and after a slight acceleration and letting off the throttle it stalled. The first time it happened I could smell gasoline (the tank was also nearly empty). I did some data recording but could not reproduce the problem. I would attach the files but it says they are invalid type... Later I checked my catch can and I believe there was some gas in it as well as the dip stick smelling slightly gassy. There are no engine lights and it otherwise seems to be running OK.

Where do I go from here to be sure and find the leaking injector? I have seen videos of listening for the ticking and checking the ohms but haven't done that yet. I know that can help find a "bad" injector but would it find a leaking one? Any help would be appreciated!

Also the engine was rebuilt a couple years ago with a Trilogy (60lb injectors) tuned by Lidio.

justbob
10-12-2017, 07:16 PM
If it's stalling and your smelling gas I'd look into the FRPS.


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Cougar_Marauder
10-16-2017, 01:41 PM
I only smelled gas while waiting at the stop light just before the first time it stalled.
I checked for any fuel smell in the vacuum hose attached to the FRPS and there was none. I also took the FRPS off to try and blow through it and I couldn't. There didn't appear to be any pressure in the rail when I removed it but I haven't started the car in over a week now. I have a fuel pressure gauge on the way.

BLACKMARAUDER04
10-16-2017, 05:04 PM
check your air idle valve. It can cause stalling.

Cougar_Marauder
11-06-2017, 03:00 PM
So I'm back to square one on this. I did the sound check on all my injectors and they sound good. I put a fuel pressure gauge on the rail where the Schrader valve was and it is only reads 30psi but data logging shows me at 40psi, so I bought a new FRPS. No change with the new sensor. So did I get a bum gauge? or could this be a sign of a failing pump? I also tried cranking up the boost-a-pump but that made no difference. The pump is an Aeromotive Stealth 340, maybe 2 years old.

Turbov6Bryan
11-06-2017, 03:07 PM
There's a local guy here that cleans injectors for 10 bucks each plus shipping

Lsxkilr custom calibrations

They are on Facebook too

If it's dying I would put a gauge on it, and watch the fuel pressure. I bet the 2 year old fuel pump is dying.. use a gauge and a buddy

Fastbob
11-06-2017, 04:04 PM
There's a local guy here that cleans injectors for 10 bucks each plus shipping

Lsxkilr custom calibrations

They are on Facebook too

If it's dying I would put a gauge on it, and watch the fuel pressure. I bet the 2 year old fuel pump is dying.. use a gauge and a buddyOr a gauge duct taped to the windshield so you can see it.

ByronRACE
11-06-2017, 04:17 PM
If you think you have a leaky injector, pull all 8 plugs, remove all 8 coils, cycle the key on and off about 50 times to cycle the pump, then hold the throttle to the floor and crank it for a second. The hole that shoots fuel out is where the leaker is. Holding the throttle floored during cranking turns all 8 injectors OFF. Caution; you CAN bend a rod if you do this with the plugs in and a bore is full of fuel. It can hydraulically lock the engine at a point where the leverage on the small end of the rod during cranking is high enough to bend it. We had the misfortune of this happening after installing brand new ACCEL injectors in a brand new Cobra back in the day. The mechanic keyed on a few times and witnessed weird fuel pressure behavior, saw no leaks, then cranked it anyway. BANG.

Fastbob
11-07-2017, 06:03 AM
I would think that if you have a leaky injector there should be evidence of that on the sparkplug in the affected cylinder. Perhaps remove all the plugs, take a close look for deposits and compare their color.

FordNut
11-07-2017, 09:35 AM
As for the pressure gauge, it probably reads fuel rail referenced to atmosphere. The FRPS (and PCM) reads fuel rail referenced to vacuum. About 10 psi difference.