View Full Version : WHOOPS! Car is running very rough

02-19-2008, 09:34 AM
I was driving happily and decided to open up my car a little bit on a stretch of road before going back to work. Well I had a very high pitched squeal but the car drove fine for a 100 yards back into the work parking lot. I pop the hood and I thought i blew a hole in my downpipe that i welded. I almost sounded like a kettle. I shut her off and let her cool down before i stick my hand in the engine bay. I went back and started her up again and the noise was ther eand very faint. i thought i dodged a bullet...well a CEL popped, I don't have a vag-com here so i don't know whats up. I have some limited tools at work So i might pull the head to check my timing and such on the cams. Its running VERY rich at idle at 10.0 and it holds very steady there. Whats going on?

02-19-2008, 09:50 AM
exhaust gasket [confused]

If your running very rich, your car more than likely threw the CEL because of that.

02-19-2008, 09:52 AM
not running one or a turbo to mani gasket. I found the DV hose back to intake fell came off which is why it was running very rich at idle. I fixed that and now i'm back to 15.1ish but the motor was still running the same. I think I fouled up my plugs running that rich or my ecu adaptation is way out of whack now. I disconnecting the battery and ecu and see what happens from there. I'll pull the plugs to clean as well.

02-19-2008, 09:55 AM
so what was the squeal?

02-19-2008, 09:58 AM
hhhmmmm i dunno. haha

02-19-2008, 10:09 AM
you will need to drive the car some to clean the plugs off (or replace them) and like you already did, make sure to reset ecu/adaptation

02-19-2008, 10:17 AM
you will need to drive the car some to clean the plugs off (or replace them) and like you already did, make sure to reset ecu/adaptation

2 questions:

1. is it ok to drive the plugs clean If the car's been running rich for a while?

2. If you dont reset the adaption, wont the car just readapt itself?

I'm curious because I keep fixing boost leaks, but i dont reset the adaption everytime i fix one. I just figured the car would adapt to the better conditions...

02-19-2008, 10:22 AM
i think ive only ever taken a set of plugs out once to clean them...all other times ive just driven the car..not ideal..but neither is cleaning them..ideal would be replacing them..and im lazy

its always good to reset adaptation after making any sort of changes

boost leak i wouldnt worry so much about but in his case where the car was running super rich it would be required

02-19-2008, 10:26 AM
The car is still running like ass. It barely moves. My AFR is like stuck on 10.0. Whats causing the ecu to dump so much fuel? I don't think i have any intake. I'm pretty sure its just bogging down on fuel.

02-19-2008, 10:29 AM
check block 031 w/ vag to see what your o2 sensor is reporting ..002 as well to see what maf is reporting

if o2 sensor has failed and sending a 0v signal to ecu then ecu will dump fuel because it thinks the car is running super lean ..ive had that one happen before

edit: you arent feeding your ecu 0-1v o2 sensor signal via a wideband controller by chance are you ? ..thats what happened to me..0-1v output on controller died so ecu received 0v signal from "o2 sensor"

02-19-2008, 11:03 AM
sigh. looks like I need a tow home.

02-19-2008, 11:24 AM
that sucks man... sorry to hear. Hope you get 'er running soon.

02-19-2008, 11:38 AM
Call tap and ask

02-19-2008, 11:44 AM
I think the only logical explanation is maybe a skipped timing belt. The car runs the same with out with out the maf plugged in so there could be an issue there. I'll have to see what codes I get. Hopefully its someone easy and stupid. I need a beer.

02-19-2008, 11:47 AM
how is that logical?

skipped timing belt isnt going to make the car run rich

it will run basically perfect 1 tooth off and anything more than that you would probably smash some valves

you need to check 031

02-19-2008, 11:51 AM
yeah i'll definantly check that when i get home. DAMNIT I WISH IT WAS SOMETHING SIMPLE! now i got to ride home with a wierdo tow truck guy

02-19-2008, 12:25 PM
Sounds like the maf might have died causing the car to run on the fuel map only. I had this happen way back when I was running the T28 kit and the reason my car ate up a few rings because I was driving around with it running so rich.

Driving the car around without the vag in the car is just a NO NO.[eek]

02-19-2008, 01:21 PM
its just that my laptop battery is shit right now. I usually have one on me =(

I just got home. Check out things now.

02-19-2008, 01:31 PM
Looks like kompressed nailed it. O2 sensor died instantly. WTF? I'm checking the wiring to see if its something else

02-19-2008, 01:53 PM
block 31 is .435 primary and .425 secondary when the car is running and when the car is off....what the heck is going on? Also the purge valve is shorted or something.

02-19-2008, 03:12 PM
5 Faults Found:
17833 - EVAP Purge Valve (N80): Short to Ground
P1425 - 35-00 - -
17955 - Boost Pressure Regulation Valve (N75): Short to Ground
P1547 - 35-00 - -
17880 - EVAP Leak Detection Pump: Short Circuit to Ground
P1472 - 35-00 - -
16486 - Mass Air Flow Sensor (G70): Signal too Low
P0102 - 35-00 - -
16518 - Oxygen (Lambda) Sensor B1 S1: No Activity
P0134 - 35-00 - -

how are these codes related? they all popped up at the same time. I didn't have these before. I tried a new o2 sensor and no luck. its definantly and electrical issue

02-19-2008, 03:25 PM
aaaahhh found the culprit. Two blown fuses. Number 29 and 34

02-19-2008, 03:27 PM
maybe a surge of power from the alternator? then overloaded the battery and blew everything up. Idk...

I dont know what the squeel would be though.

02-19-2008, 03:34 PM
The fuses aren't the culprit... They don't blow from old age!

02-19-2008, 03:35 PM
Well see how she does on the road test. I have to add its not the first time it squealed.

I know why I had a short somewhere. I had a coolant leak because I had a TINY pinhole on my coolant feed line to the turbo spraying everything on that side. Now I have to locate the short....its either the n75, leak detection pump or evap purge because the maf and o2 sensors read fine.

02-19-2008, 03:36 PM

I hate when I hear someone say, "Yeah I had a blown fuse so I replaced it and everything is ok."

02-19-2008, 03:37 PM
Atleast its not mechanical though. I'm relieved its just an electrical short somewhere. I just wonder why it took 4 days to finally blow a fuse.

02-19-2008, 04:21 PM
at least it sounds like an easy fix for the most part

and you know basically what the problem is

02-19-2008, 04:29 PM
It runs fine now! yay! I have a rough idle though because when I was poking around I must have created an intake leak somewhere...probably the dv recirculation hose. I was getting some compressor surge so I think its that hose.

02-19-2008, 04:33 PM
this BAT status day number what?

02-19-2008, 04:43 PM
day 12 aka the day I thought i blew up my motor