runs good one day bad the next

[hansfase]

hello, i have a '92 eagle awd with a 47trim turbo upgrade and it almost always runs bad, the cars power flatlines with boost and can only be driven at 0psi hardly even exelerating.
some times i might get lucky and it will run great for a minute, but most of the time it is running bad. i gan also drive the car all over the countryside at 0psi and still only get like 12-15 mpg. i have replaced the knock sensor, fuel filter, plugs, wires, and ecu, now i am pulling my hair out. i have also tryed hooking it up to a snap-on code reader and it had problems communicating. HELP!! PLEASE!!!

 

[Mr Peepers]

Have you done a boost leak test lately?

 

[Dream On]

If it's getting that bad of gas mileage, I'd bet the o2 sensor is shot. Boost leak test would also help. If you can't get the scan tool to work, find a friend with a logger or just hook up a 2 wire speaker to the diagnostic port and read the codes manually.

http://vfaq.com/mods/wayback/BradBauer/electrical/code.html

 

[hansfase]

i havent found any boost leaks and my o2 isnt throwing me a chec engine but i do have another i can toss in and see if it helps

 

[HIGHPSI4]

Sounds like a bad knock sensor.

 

[hansfase]

the car has a brand new knock sensor on it, put it on myself. i also replaced the coil pack.

 

[Turboeagletalon]

your waste gate could be stuck open. Your timming could be way off. Do a compression test and rule out internal motor problems. BAd mass. runnig way to rich my couse that problem.

it sounds like your turbo isn't spolling

 

[hansfase]

well i have done a compression check already and i had 135psi across the board, the turbo is new and the actuator is turned all the way up and i can see that the actuator arm is in the right position. i also have two maf sensors and i have tryed swaping them out with the same resault. also i have pulled the plugs a few times and they were pure white near the electrode and slightly grey up top.

 

[Turboeagletalon]

could be a bad ecu also could be a bad coil pack.

try pulling the injector plugs of one at a time to see witch one isn't fireing fuel properly

 

[hansfase]

the ecu was the first thing i replaced and i swaped out the coils a few weeks ago, along with the injectors. i will try checking the injectors out again though, seeing as how it does feel like its starving for fuel i have also thought about sending them off to be cleaned. today i am having someone check out the filter thats on the fuel pump, i was also contemplating if the fuel pressure regulator mich create symptums like im having.

 

[Turboeagletalon]

also make shure your getting good fuel pressure. Your fuel pressure regualtor could have gone bad. And your your pump. I highly recomend doing a re-wire on it for it so it's getting a beture power source then 18g wire

 

[black91awdturbo]

white plugs show its running hella lean not rich, to me it sounds like you have a piss poor fuel pump thats on its way out! Do a fuel pressure test and that will most likely answer your problems right there.

 

[Turboeagletalon]

i agree

let us know man. im interseted to hear what happens