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View Full Version : Car studders under low throttle


Pimpin Dsmstyle
10-21-2007, 11:42 PM
I got about 500 miles on the car since I put it all back together. When it gets a cold start up, it gets some idle surge but once it warms up, it goes away. The emissions are blocked off so that may have something to do with that. 92 talon TSI AWD Turbo, small16g 450cc injectors, 255FP, adjustable FPR and full 2.5 exhaust. Other than that, it's 100% stock. I know the car could use some kind of injectors and fuel control but I doubt that it has anything to do with my problem.

Now the problem is under low throttle ( traffic situations mostly ) the car doesn't accelerate smoothly. It feels like im tapping the gas and letting off of the gas, kinda jerky and what not. If I give it moderate gas or WOT, it doesn't do this at all. It is only under light throttle and while the car is not up to temp.

The ECU is my first assumption, but seeing as I am 100% broke, I figured I'd search for some other ideas before I go and buy an ECU. Idealy, finding an ECU just to swap in and test would be the best choice. Any other ideas? Any support to the faulty ECU idea?

The reason I think it could be the ECU is because I had an eprom in my other car, sold it and swapped this one in and if my memory serves me correctly, it did the same shit in that car. It's been about 5 months since I drove it since I stripped it down very shortly after swapping out the eprom for a stocker.

Andrew7dg
10-22-2007, 11:17 AM
I am guessing you did a boost leak test?

I live close to you. I should just drive over and look at it...

I have something that you can test for boost leaks.

Also do you have a boost gauge on the car? anything weird happening there?

Usually if it is the ECU something would just cut in and out. However when the ECU does burn out, results do vary

AwdGSX13
10-22-2007, 05:46 PM
my car did this when it had a large boost leak... what i did to fix it was remove the IAC sensor/motor and i removed the FAIV and installed a plate. because even though the actual surging went away it was still their when it was idling in gear in traffic, it would hop... very annoying. Do a boost leak test. also i do live close also, if you need help.

Pimpin Dsmstyle
10-22-2007, 06:23 PM
I don't have the items used for a boost leak test. I'm pretty sure there is some kind of leak near the intake manifold but the IC piping should be fine. It gets worse and better constantly. It could be a million things but I wanna try get ahold of an ECU I can just throw in and test out.

Pimpin Dsmstyle
10-22-2007, 06:23 PM
I don't have a boost gauge in the car currently. There is nothing wrong under heavy load, just light throttle and now it doesn't like to run after it starts. BOO

Andrew7dg
10-22-2007, 07:33 PM
I have the stuff at my house to test for a boost leak if you want

PM me if you are interested
I am like a block away

Pimpin Dsmstyle
10-23-2007, 12:57 AM
I'll let you know when I got time to mess with it. My garage is a fucking mess from hell right now and I work lame hours. Thanks for the offer and I'll likely take you up on it soon.