View Full Version : help: idle/running problem

Lazer Viking
08-11-2010, 12:28 PM
The other day i was driving, and one of my wheels came loose, so i pulled over to tighten it.. when i went to restart the car the battery was dead, so jumped the car and got it home, and it was idling like shit, real low idle and would want to die out anytime you touched the gas.. came to the conclusion that my alt was dead, because the volt gauge was reading real low, so i put a new one on.. didnt solve the problem. tested the battery and it was on its last leg, so i went to swap a new one in and wasnt paying attention after a long day at work, and hooked the terminals up wrong, and fried my starter. replaced both the battery and the starter and were back to square one.. it starts and idles real low, at 500 (ever since i owned the car it idled higher then normal @1000rpms) i can blip the throttle and its fine, and can hold the throttle and its smooth and fine.. untill it hits 1500rpms then it falls on its face and wants to die. every time it reaches 1500rpms it dies out, then recovers back to its 500rpm idle.

cliff notes: battery was dead.. i fucked shit up, but fixed it.. car idles @500 rpms and anytime it reaches 1500rpms it falls off and wants to die
99.5 aeb car, 50trim t3/t4 unitronic 440 file and 3" vr6 maf

so to me it sounds like a sensor problem, where should i start ?

08-11-2010, 12:35 PM
Check stupid things first. Did you forget to plug the maf back in?

Lazer Viking
08-11-2010, 12:37 PM
never unplugged it, this issue started before i even touched it.. it started right after the battery died, if thats at all related

08-11-2010, 12:38 PM
have you driven it at all?

Lazer Viking
08-11-2010, 12:43 PM
no, figured theres not much of a point if i cant exceed 1500 rpms.. haha

08-11-2010, 12:45 PM
I would try driving it around the block. Maybe the ecu is going of the last readings of when you stalled and it just needs to adapt.

Lazer Viking
08-11-2010, 12:56 PM
i'll give it a shot, but the ecu was unplugged for more then a day, and the battey was disconnected for two days.. when i first started the car again the cel was off for a minute, then came on.. so i think the ecu was clear.

08-11-2010, 12:58 PM
maybe you will pull a code and get closer to figuring out the issue

Lazer Viking
08-11-2010, 01:03 PM
yea, unforunatly i dont have vag com installed on my lap top, and i let a buddy borrow my cable, so i wont have access to that till atleast tommorow

Lazer Viking
08-11-2010, 05:58 PM
anyone else ?

08-11-2010, 06:02 PM
anyone else ?

Without a vag-com you can do a throttle body alignment, try that. Otherwise get your cable back, you need it.


Lazer Viking
08-11-2010, 06:02 PM
found a very similar problem.. dosent look like they checked back with the actual soulution though

08-11-2010, 06:49 PM
After reading that thread is sounds like you may have fried your ecu or tune when you fried the starter.

A war of 4
08-12-2010, 04:07 AM
Unplug the MAF and drive it. If it runs better you probably have a large boost leak. What's the boost gauge showing? I had a diverter valve hose pop off and acted pretty much the same

08-12-2010, 06:10 AM
After reading that thread is sounds like you may have fried your ecu or tune when you fried the starter. who says that, if his ecu was fried it wouldnt run....i have something called fun with electronics, i played with it when i was eight....maybe you can borrow it sometime....this is like the 15th thread this week with dumb advice...as for your issue....start with battery wires, i had a similar problem...next, start with small things, check your packs, plugs...if it came on suddenly it sounds sensor related...but you never know

08-12-2010, 07:27 AM
If you read the thread that lazer posted, someone fried their ecu and was able to start and idle up to 1500.

I'm not telling lazer to buy a new ecu just saying its a possabilty. He won't know anything till he gets his vag com back.

08-12-2010, 08:06 AM
thats a freak instance, and it happened before he even touched it...so ...wrong.

Lazer Viking
08-12-2010, 11:13 AM
there is no boost leak, already checked that.. this all started after the battery went dead, and i started it with a jump box.

i just swapped in my stock ecu, and the problem went away.. so there are either still stored codes on my tuned ecu, or its toast.

08-12-2010, 02:42 PM
check your throttle angle at idle. maybe your throttle cable got moved. Also try a throttle body adaption.

Lazer Viking
08-12-2010, 02:51 PM
only did the old fashion key in ignition after battery disconnect style tba, and it made it better.. before i did that i couldnt even blip the throttle from idle without it trying to die

Lazer Viking
08-19-2010, 05:49 PM
sooo update, my ecu is toast.. vagged it today and all the codes cleared and were fine, but could not get the tba to connect, and the values were all reading at 0 so its not communicating with the throttle body at all. with the stock ecu everything works fine.

Lazer Viking
09-01-2010, 02:50 PM
another update, just got my ecu back from unitronic and everything is good to go.. glad i have it back after almost a month