M50NV cuts out going from idle to WOT

[lolcantturn]

Hmmmmmmmm...that seems kind of correlated. you see, sometimes I feel like I hear an intake backfire? I feel it in the throttle pedal, which can be from the cam sensor fucking up..

[blueapplesoda]

cam sensor sends a signal to the ECU to decipher which cylinder is on what cycle, for sequential fuel and spark.

[trackjunkie21]

Cam sensor retards/advances ignition timing

[blueapplesoda]

Sometimes they go intermittently bad. get some known good ones and try it couldn't hurt

[lolcantturn]

I think a failing crank sensor would disable the motor completely from starting right? What does the cam sensor do? Because I'm thinking it's that..

[blueapplesoda]

crankshaft sensor? camshaft sensor?

[lolcantturn]

changed the ECU, NOTHING.
changed the fuel pump, NOTHING.


:(

I mean I don't have my purge valve connected and the vent line from the fuel tank is just venting to atmosphere but i DOUBT that's it.

[lolcantturn]

Texted!

On another note, I'm thinking its a very serious fuel delivery problem.
the only CODE I get is 1263, which is Fuel vent which is the purge valve that I don't have connected, the vent line from the gas tank is just chillin in my engine bay

When I went WOT from a launch, the car hauled ass in 1st gear, then as I went to shift into 2nd it just immediately died. The car was cold too so i can't imagine it being related to coolant temp sensor since it wasn't at operating temperature.

[gp.plus]

You can't just keep throwing parts at it. Check your fuel pressure. I'll mail you my test kit if you want. Text me

[lolcantturn]

I'm still getting complete cut outs and complete motor death on the highway at cruising speeds. I'll be driving at cruising speed, then it'll start cutting out, then i'll try to keep the revs up by giving more throttle but it doesn't do anything, then I'll downshift to 4th to keep the revs up which either saves it or kills it completely..then the motor will be moving while still in gear, but absolutely dead.

Could my coolant temperature sensor be causing this? because it seems to happen at only operating temperature.

[lolcantturn]

ICV me thinks.

Do you have a multimeter? If you do, try testing your tps sensor. Also, its a long shot but have you tried playing with the adjustment of your throttle cable? Maybe theres too much slack?

If you dont have a meter, it wounldnt hurt to try and change both the icv and tps. Both items will amazingly fit in your pocket nicely if you just so happen to hit up a local pick a part.:D

Lastly, try unplugging your idle control valve to see if anything changes....

Unplugged my ICV while car was cold and the idle was surging, nothing happened except a CEL! Time to give it a good cleaning?

Man, i thought you were all good, then i see this. I agree you should start by checking the fuel pressure w/gauge, you could have a clogged filter, or the pump may not be keeping up at wot. The icv should not cause issues beyond idle, as more than enough air is flowing through the tb. grab a fuel pressure test kit from harbor freight, clean it up and return it when done, or see if autozone "lends" them, i believe they require a deposit but there is no rental charge.

have you checked for vac leaks w/ a can of carb cleaner? spray it around possible leaks and listen for the idle to increase, try spraying the injectors, good chance the lower o-rings are toast. i pulled a set w/185k on em , and the o rings literally crumbled off.

I've tried vac leaks with carb cleaner and I can't find anything, im thoroughly convinced I have none!
The problem with it surging and cutting off at high RPM's seems to have gone away with the FPR though, it just cuts off at idle now when it's surging and I go WOT.
fuel pressure test will be my last resort

[gp.plus]

Man, i thought you were all good, then i see this. I agree you should start by checking the fuel pressure w/gauge, you could have a clogged filter, or the pump may not be keeping up at wot. The icv should not cause issues beyond idle, as more than enough air is flowing through the tb. grab a fuel pressure test kit from harbor freight, clean it up and return it when done, or see if autozone "lends" them, i believe they require a deposit but there is no rental charge.

have you checked for vac leaks w/ a can of carb cleaner? spray it around possible leaks and listen for the idle to increase, try spraying the injectors, good chance the lower o-rings are toast. i pulled a set w/185k on em , and the o rings literally crumbled off.

[e46s54dr]

Do you have a multimeter? If you do, try testing your tps sensor. Also, its a long shot but have you tried playing with the adjustment of your throttle cable? Maybe theres too much slack?

If you dont have a meter, it wounldnt hurt to try and change both the icv and tps. Both items will amazingly fit in your pocket nicely if you just so happen to hit up a local pick a part.:D

Lastly, try unplugging your idle control valve to see if anything changes....

[trackjunkie21]

ICV me thinks.

[lolcantturn]

Definitely check your fuel pressure with a guage. If the pump is weak or dying, it wont be able to pressurize the fuel lines in time. Have you tried reving the engine and keeping it steady at say 5k rpm? Try that and see if it hesitates or even dies out.

Holds it steady.

Tps

You think so? What makes you so sure? Will buying a known-working one cure my idle?
I vaguely remember my idle on my M20 improving somewhat dramatically when I changed the TPS.