HELP ME PLEASE-GS-T boost coughing kinda

I went to the dealership...i know thats stupid in itself but i'm lazy..they tell me they charge 70 bucks an hr to check for the problem and theyre sure it will b a lot of money to fix.. :nono: ..so screw them

i have a a 1990 eclipse gs-t and since i bought it i have not been able to floor it past about 4000 rpm..this is where the boost climbs up around 14 psi...whenever i get that high the engine sort of coughs...it feels like ive reached a rev limiter and it releases a lot of black smoke...so i figure i have an air leak sumwhere...probably around the intercooler or piping...i dont know where it is and i dont really wanna spend too much money figuring out where it is.

recently i have taken off and plugged the piping that goes from the BOV back into the turbo...i think its called sumtin bout bypass.. anyways idk i took i off just to sound cool...and for no other reason...this increases lag and all that and i eventually got tired of it being off (even tho it sound beautiful :iceslolan )...

the problem in my air leak theory is that when i hooked this pipe back up..for the next day i could floor it all the way to redline...the problem dissapeared for that one day...this leads me to think that it is a computer or sensor problem...maybe a sensor is telling the engine not to let in as much air or to let in too much fuel..i dont know... :banghead: ...please sum1 help me

So.... you are still venting the bov? If so, put it back on! That could explain the smoke. Venting causes you to run rich.

so i figure i have an air leak sumwhere...probably around the intercooler or piping...i dont know where it is and i dont really wanna spend too much money figuring out where it is.


Put the BOV dump tube back on and check for boost leaks.

ya i put it back on already, and i knew it made me run too rich and burn fuel...i did it just for the noise...the point was that when i put it back on the problem went away for that day...later the same problem would come up again

iit just confuses me that taking the pip off for a couple days and then putting it back on would have any effect on the problem...i dont understand wut effect that would have on a leak so i figure it must b a sensor or the computer but no check engine lights r on so i dont know

If it feels more like a stutter at higher boost it might be the gapping of your spark plugs....
When I was trying to find the "sweet spot" for my NGK's and I had the gap too big it stuttered at about 10+psi... once I got it, the stutter went away... just an idea of something to check for...

I agree with the plugs. Get correctly gapped NGK plugs. If you vent to the atmosphere it only makes you run rich when you shift, not under acceleration. If you think it's an air leak make a leak detector thingamajig. It's on a site but I don't remember it. Can someone fill in the blank?

It's a boost leak tester and it is found on www.vfaq.com it is a must for anyone with a boosted car.

If it feels more like a stutter at higher boost it might be the gapping of your spark plugs....
When I was trying to find the "sweet spot" for my NGK's and I had the gap too big it stuttered at about 10+psi... once I got it, the stutter went away... just an idea of something to check for...


That's great info. That's exactly what my car is doing right now so I'm definately going to buy some new plugs and wires.

I would highly suggest the NGK's BPR7ES-II
Boostedspyder suggested them to me quite a while ago and I got them... he said to gap them at about .030... I ended up tweaking them down to .027 to get rid of the boost stutter....
Once the stutter was gone there was a noticeable improvement in acceleration and smoothness of engine... great upgrade especially if you boost higher than stock.
I had done a write up on SPARK PLUGS a while ago and it was made into a sticky... but it was removed and not put back up... if ya do a search .. there is a ton of great info in it....

If you find that the plug gapping isn't your problem, check the coil pack. Mine was bad when I bought the car, and It would boost fine 'til it started to get around 10 psi and then It would stutter horribly. It was actually faster if I didn't step on it. But anyhow, somehow one of the coils on my coil pack burnt itself to a crisp and was sending a very low voltage(if any) spark to my cyl1.

THANK YOU...it is a stutter exactly...i havent even changed the spark plugs and the ppl with the car b4 me didnt take care of it too much...lol...i should probably try that

i think it is problem solved....its kinda wet outside so i cant test it out too much...i loose traction right around the time that the problem would occur and the boost drops down cuz im just peelin tire...thank you every1...ive had that problem for way too long

damn...that was way too easy...im almost dissappointed that the problem was such an easy fix cuz it was bothering me for awhile...thank you so much every1.

2 years ago when I bought my 96gsx 5 speed w/112k, I used that exact problem to talk my manager into letting me buy it for $3500. He knew I was full of shit, and let me buy it anyway. Sorry I didn't read this earyer. Nothing like a simple fix!