What in the hell?

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Okay. I just bought a 91 GST tuesday. This is my 2nd car, first import, first turbo, and first car I plan to mod. I took my sister for a drive today, and of course I had to show off the boost, so I was in first gear and I floored it. Once my boost kicked in it boosted for about 500-1000rpms and then started cutting off like the car would jerk forward then the boost would kick in again and it would keep repeating this cycle over and over again like i was flooring it, slamming the brake, and flooring it again. My sister said it sounded like a grinding noise coming from under the car, I didnt hear it, I think it may have been the bov/wastegate? Anyone have an idea? I got some cheap ass no-name boost controller that came with the car and yes i have a boost gauge. someone please help me, this aint cool. ps..when i accelerate slowly it doesnt do this..

 

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update::it cuts off at 15psi every time according to my boost gauge

 

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can anyone help?

 

[Colossus]

Sounds like fuel cut. Bucking/jerking feeling? The ECU is seeing more airflow than it should, and can't correct the air/fuel mixture. So, it's cutting the fuel off. It's not something you want to do often. I suggest to do a search for Fuel Cut, and read what all information there is. It should help you out! Whatever you do, don't go with a Fuel Cut Defencer. You're gonna be looking at an S-AFC, and possibly bigger injectors to make more boost safely and correctly.

 

[turbo90gsx]

When my car did that it was the alternator. The alternator just stoped working so it wasn't suplying power to the spark plugs, therefore it kept freakin out. I know what your talking about....its not fun to be in the car when it does that. Does it back fire as well?

 

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i dont think it backfires.. Colusus described it well..I need to hook up the stock wastegate selenoid, can someone tell me what size vacume tubes i need to get for this please? Im gonna wait and save up for a Profec-B II

 

[boosted95]

could be a boost leak.

 

[turbo90gsx]

1/4 vacume hose, or 3mm. I have the profect b-spec 2. I rocks pretty hard. You have to play with it alot to get your personal settings correct though. It aided my spool up time 250 rpm's though!

 

[Render]

sweet...ill have to save up

 

[me612]

Ya sounds like fuel cut to me as well. Bigger fuel pump should help cure this. I still remember my first encounter with fuel cut. So violent that u look behind you expecting to see your tranny laying in the road.

 

[Render]

hahahaha yeah..thanks for your help by the way guys