My Dsm Problems

[paultheninja]

So when I first start up my car, the idle bounces extremely high. Sometime it will even reach 2k. Then after 30 or so seconds, it will idle down to about anywhere from 800-1200. It will bounce there for awhile.

Also, when I am driving around town, sometimes when I come to a stop light, my rpms will drop to around 100-300. If I don't play with the gas, it will die.

Im pretty sure this is a fuel problem, but im not 100%. Any help would be appreciated.

 

[buryurfear14]

If it runs fine under load it shouldn't be fuel, it sounds like a vaccum leak to me. You can use carb cleaner or brake cleaner around your lines and see if the idle kicks back up. Notice any change in your brake pedal? Also do you have a dvom?

 

[TuRBoTaLooN]

You could also try playing around with the BISS screw or see if you're leaking around that o-ring.

 

[buryurfear14]

The low rpm stall issue culd also be overfueling, give us more info on the car and driving conditions

 

[paultheninja]

The only reason why I thought it was a fuel issue is when I changed my injectors out, the problem went from being 100% to only 10%. Driving conditions are 50/50 town and highway, in Indiana weather.

I have had a vacuum tester hooked up, and no vacuum leak. My car is a 96 Eagle Talon TSI AWD A/T. Current mods are just Big 16g turbo, intake, and FMIC. I am only running 10psi at the moment. It usually only does it if I am doing some heavy acceleration, and short stopping, but not always.

One of my friends told me it might be my fuel rail. Nothing is wrong with my brake petal, it is acting the same as it always has.

 

[3parks]

Are you venting to the atmosphere? I know that can cause the car to die at stops sometimes

 

[quiksilver38]

change the o-rings on the throttle body shaft just to be sure. also +1 on checking BISS screw

 

[paultheninja]

No not venting. Are the BISS screw just the idle screw?

 

[91 TSi GP]

it is right on the throttle body if you lean over the front of your car its down a little countersunk hole. its probably the size of a nickel

 

[95'RS-T]

So when I first start up my car, the idle bounces extremely high. Sometime it will even reach 2k. Then after 30 or so seconds, it will idle down to about anywhere from 800-1200. It will bounce there for awhile.

Also, when I am driving around town, sometimes when I come to a stop light, my rpms will drop to around 100-300. If I don't play with the gas, it will die.

Im pretty sure this is a fuel problem, but im not 100%. Any help would be appreciated.

is the CEL on? do you have a A/F gauge? kinda sounds like a TPS or a bad o2 sensor to me the o2 sensor would explain the high idle as well as a vac leak too, but since you did a vac leak test that couldn't be the case. Well the only thing I could tell you is see if your car throws the CEL.

 

[paultheninja]

No A/F gauge... im in the midst of ordering a triple pod gauge (if anyone knows where to get one for cheep let me know).

With the BISS screw are u wanting to make my idle go up or down? And im not sure what a CEL is.

 

[buryurfear14]

You replaced stock injectors with what? Did you do a tune to adjust for the larger injectors? Sorry if I'm missing completely on this.

 

[paultheninja]

Oh no no no srry. I replaced with stock injectors from a friend. Someone mentioned using seafoam to check for leaks. I think I might do that today.

 

[TuRBoTaLooN]

Oh no no no srry. I replaced with stock injectors from a friend. Someone mentioned using seafoam to check for leaks. I think I might do that today.

Seafoam will only check for exhaust leaks really.

You said you did a leak test and you're not leaking so I'm assuming your BISS screw o-ring is fine. And yes, the BISS screw is the idle screw. Just try turning it both ways to see how it affects your idle situation. If it's too open or too closed, the ecu may be trying to compensate for it by adding gas or something and throwing it all off.

Also x2 on checking your front o2 sensor. That could definitely cause these symptoms.