cant boost, hesitation, bogging and power loss

[Nightmare]

I've been trouble shooting this thing for 5 days, so here is my scenario.

One day on my way to work, half way there, the car began to bog, hesitate and back fire when i began to enter boost. Since then, ive noticed the car works mostly alright if its JUST started, not warmed up, but after it begins to get hot, i cannot enter boost. I CAN go all thorugh the rpm band if i stay out of boost and accellerate slowly, but as soon as i hit even 2-3 psi, i begin the bogging and the hesitation and backfiring and complete loss of power.

I've tested for ecu issue, maf sensor, coils plugs and wires, all boost leaks, scanned all my cel's (high circuit maf - fuel cut frm trying to get the car to act normal) and i am now at wits end. I just put the timing belt back on thinking it may have skipped a tooth. I found the tensioner was loose, but the timing was still good.

I didnt get a chance to test drive it after i put the belt back together, but i am also getting tired of throwing parts at it. It just happened all of the sudden, i had done nothing to her prior to this for about a week or so.

motor related mods..

built cunningham rods, weisco pistons
1.8l coils and wires
tubular manifold
14b
2.5'' to 3'' dual tb exhaust
removed vtcs and vics
fmic, hard pipes and rfl bov
removed egr and evap
removed a/c
p5 radiator
mbc 10 psi

and some other junk im sure im forgetting..

Anyone have any suggestions?

 

[terbow]

whats ur vac at idle?

 

[Nightmare]

21~ sometimes it dips to 18, but i never thought anything of it.. It's been doing that for eons.

 

[terbow]

yea 21 is good. was checking for leaks, thatll do it every time. is the wg not holding shut? can u blow into the wg and hear it comeing out? or does the rod jiggle if you yank on it?

could be maf related too.. mine got wet somehow and man it sucked just like your saying. my maf wire had a black spot on it, maybe take urs out and see or try swapping one with someone u know? i never got a CEL but it would do what urs is.

 

[Nightmare]

My wg is an old dsm peice, rod is really firm, and cant say i ever tried blowing into it. Though i will try tomorrow. it had crossed my mind that the wg could be freaking out under load.

I have traded maf sensors with a friend of mine twice in the past 3 days and it acted exactly the same as my origional maf. so im ruling that one out, for now.

This car can be incredibly fustrating.

 

[terbow]

any turbo car can be like that man, ive been there lol.

glad u ruled out the maf tho, those are like 300

 

[GoProtege]

Maybe a failing 02 sensor? Last time mine went out it kind of acted like that intermittently for about a week before it threw a CEL

 

[Nightmare]

Just took it out for a test drive again, checked the maf and wiring, removed the mbc and finished the new timing belt.

It acts up when its cold just a little bit, when it gets warm, it suffers complete loss of power. IAT?

 

[BradC]

Just took it out for a test drive again, checked the maf and wiring, removed the mbc and finished the new timing belt.

It acts up when its cold just a little bit, when it gets warm, it suffers complete loss of power. IAT?

IAT would read the same temp when the car is cold though. Does the ECU only look at the IAT when the car is up to operating temp?

 

[Nightmare]

I just took my IAT out of line and left it hanging, my problems damn near went away -.-

im changing into the 03.5 ecu in a bit here and take it for another test drive. i find the 03 ecu has an asston of hesitation issues comparatively.

 

[ho bag]

Get back to work slacker!

But ya the car is very very fustrating. He has tried my reflashed msp ecu, my maf, new 1.8l coils everything.

When it acts up its not a hard miss like fuel cut. Its a soft miss like spark but even with new 1.8l coils it still does it.

Hopefully he gives up soon and buys a dsm

 

[Nightmare]

 

[Nightmare]

So, cam angle isnt it either. The IAT wasnt helping, it relaxed some after i took that out, but the problem persists.

it feels kinda like heatsoak, like the power is simply not there. the motor is shutting down under load, and backfires on occassion under medium acceleration. But i know its not heatsoak, i could chill a beer on my IC after a track day.

oi..

 

[crackerjakx]

Maybe a blocked cat? Just throwing an idea out there...

 

[Nightmare]

no cats, 2.5'' from the turbo to a mid pipe magnaflow that branches off to dual 3''. i dont think it gets much more free flowing.

 

[Nightmare]

Fixed, i beleive.

hooked up the scanner and went for a drive with the live data feed on, primary 02 reading was 0.43 to 0.42v, at all rpm.

peeled back the insulation, found the pink wire (signal) was broken.

7 days of WTF and it boils down to an 02 signal wire. (smash)

on a side note, the 1.8k coils and wires are secksy. (thumb)

 

[ho bag]

OMFG.........

Your saying that after all that stress it was o2 sensor reading bad, dumping gas and drowing spark out? No wonder it pulled like a bag of ass!

 

[Nightmare]

I think the bag of ass was faster.

 

[traser19]

im having the exact same problem you are,,, wat do i do to fix this,,, where is this pink wire located,,, i thought it could have been my temp sensor

 

[Nightmare]

look for your primary 02 sensor directly off your manifold above the turbo.

it could be a wire of yours, or it could be that your sensor fouled, but you would likely trip a code for that.