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View Full Version : 2.5 turbo cutout under load 3-4k rpm



Fox
09-25-2016, 01:15 AM
car is a 1992 dodge spirit 2.5 turbo manual trans, stock boost. problem started with it breaking up to the point where it wouldn't run above like 1-2k rpm (like it wasnt getting fuel) this only happened after a long drive,it would still run and drive. if you park it after waiting awhile it would be back to normal, about a month later it was then having a no fuel pump prime situation where it wouldnt have fuel at the rail and didnt hear it prime but there was still spark.
checked voltage at the pump. working fine. some debris in the screen cleaned them out (pump filter and tank isnt very old)
then its working better seems to prime start more consistently but now breaks up in the higher rpms so i ordered a walbro pump and replaced it same issue.
what have i checked or replaced?- hep sensor- plug wires- coil - new walbro 225 pump-

im thinking i could be losing voltage to the pump or possibly a fuel regulator or injector issue does this sound right? maybe barrow a fuel pressure gauge or run some wires to monitor the pump voltage while this is happening, i have no codes but feel it may be a type of fuel cut occurring from the sbec maybe the map or tps is on its way out ?

sugestions please :)

tryingbe
09-25-2016, 02:13 AM
What plugs are you using?
Do you have a wideband?
What boost level are you running?

You can test your fuel pump.
http://www.turbo-mopar.com/forums/showthread.php?74508-How-I-tested-my-fuel-flow-and-get-exact-liter-per-hour&highlight=

You can up the voltage.
http://www.turbo-mopar.com/forums/showthread.php?79747-Flow-numbers-before-and-after-fuel-pump-wiring-in-my-GLH&highlight=

Fox
09-26-2016, 02:52 AM
7 or 10psi psi its on stock boost control never changed the boost level
no wideband currently but i have one i can add
champion rn12yc at stock gap

i might try the relay mod you posted to get better voltage at the pump and also rule out an bad connection or short in the old system and it will only help when i do run more boost later on \

87blueshelbyz
09-26-2016, 05:45 AM
Connect a fuel pressure gauge to your fuel rail and duck tape it high enough on the windshield so that you or a friend can see it. Go for a ride and watch the gauge.

BBBDakota
10-19-2016, 05:23 AM
Check engine light?

Fox
10-22-2016, 10:38 PM
haven't had time to mess with this car in awhile sould be looking at it again soon, it would blink on when the cutout was occouring but store no codes, and i dont have a scanner to monitor live values

ShadowFromHell
10-24-2016, 10:59 AM
Back when I first got into these cars I had a 88 shadow ES that developed a very similar issue. Under boost it would cutout right around 4k. When it was cold it wouldn't do it near as bad so I thought it was fuel or spark. After throwing a TON of parts at it, it turned out the cam timing was off a couple teeth. Fixed that and it went away. I would start there its easy to check.

Fox
10-24-2016, 09:41 PM
sounds like a good idea, im sure the timing belt is pretty old anyway

1BADVAN
10-25-2016, 12:13 PM
haven't had time to mess with this car in awhile sould be looking at it again soon, it would blink on when the cutout was occouring but store no codes, and i dont have a scanner to monitor live values
Do you have a custom calibration? Sounds like a knock indicator light

Fox
10-25-2016, 07:44 PM
no its stock sbec2 not chipped yet

1BADVAN
10-26-2016, 02:07 AM
no its stock sbec2 not chipped yet
Ok but no codes at all? Just 55 or do you have 12 also that could indicate that the computer is losing its power connection under vibration, I saw a car do that

Fox
11-15-2016, 06:20 PM
it was the sparkplugs somehow they where all sooted up on 1 and 3 after only 2500 miles probably from cheap gas i was getting, most of the gap was filled and must have been blowing the tiny spark out now rinning 93 with new plugs and its perfect again

tryingbe
11-15-2016, 07:46 PM
Your cylinders are using oil.