ABS light on and kangaroo petrol

stufree

Member
The ABS light came on today along with the amber trinagle on the left of the dash and the flashing red symbol on the middle of the dash PLUS the 2 or 3 alarm beeps.
Had a quick look in case of brake fluid leakage or anything obvious but nowt. Started the car and the engine kept revving then slowing down by itself, hopping along the road. After a few hundred ards the problems went away but after stopping the engine for 10 minutes, the return journey was a nightmare of revving, alarm sound and lights and stalling as soon as I took the foot of the throttle, Must have restarted it about 30 time sor more in 6 mile journey.
Don't have working VCDS.
It's a 1.4 petrol X reg.
Thanks in advance for any constructive ideas!
 

PlasticMac

Member
The ABS light came on today along with the amber trinagle on the left of the dash and the flashing red symbol on the middle of the dash PLUS the 2 or 3 alarm beeps.
Had a quick look in case of brake fluid leakage or anything obvious but nowt. Started the car and the engine kept revving then slowing down by itself, hopping along the road. After a few hundred ards the problems went away but after stopping the engine for 10 minutes, the return journey was a nightmare of revving, alarm sound and lights and stalling as soon as I took the foot of the throttle, Must have restarted it about 30 time sor more in 6 mile journey.
Don't have working VCDS.
It's a 1.4 petrol X reg.
Thanks in advance for any constructive ideas!
Check out the scan register on here, see if anyone's local ish. Guessing is frustrating and expensive
Mac.
 

stufree

Member
Sadly nearest is near Glasgow, I'm in Edinburgh and wouldn't trust the car to go 100 yards at the minute never mind a round trip of 100 miles.... even allowing for the so called lockdown. Thanks anyway.
I'll check the battery - somebody mentioned it on here (and the injectors wiring loom but that was for a diesel).
 

Robin_Cox

Member
My other half's AUA car's been doing this. Air getting in - either loose rocker cover oil cap, or needing a new petrol cap with better seals both possible and may be the easiest / cheapest fixes. May also be a cracked air intake pipe. If the car is confused about the air content it will be doing all sorts of things like mixture adjustments to get the air / fuel ratio back, hence the revving / poor control. We also had 'manifold barometric pressure sensor implausible signal' error when the lights all came on the other day ; these cleared after I'd switched off and on again. Oil cap replacement definitely improved things (occasionally slightly trembly idle) ; I've not yet replaced the petrol cap. I have an inlet manifold pressure sensor to fit, but it's down the side of the engine so not an easy job. A year back we also needed to fit a new coil - that manifested itself as persistent misfires until a cylinder shut down - the coil was all cracked around the back and sparking through the casing. Year before that it was the throttle body / EGR that were full of tar. Your symptoms sound more like the air mixture being a bit out at the top of my list.

Best of luck!
 

stufree

Member
Hi Robin,
Thanks very much for that. I swapped over the MAP sensor for the MOT less than 100 miles ago but the EML came back on again. Did have the "implausible signal error, P0106 if I remember rightly but, with the new sensor that changed to 2 different codes- but still related to air intake pressure. Since the garage said that the EML light wasn't a fail for pre July 2003 cars I just left it - been kinda cold to be working out in the street on the car lately!
I'll have a root around tomorrow and try to see if you're right but as you've described the symptoms spot on it onds very likely. Fingers crossed.
 

Robin_Cox

Member
Hi Robin,
Thanks very much for that. I swapped over the MAP sensor for the MOT less than 100 miles ago but the EML came back on again. Did have the "implausible signal error, P0106 if I remember rightly but, with the new sensor that changed to 2 different codes- but still related to air intake pressure. Since the garage said that the EML light wasn't a fail for pre July 2003 cars I just left it - been kinda cold to be working out in the street on the car lately!
I'll have a root around tomorrow and try to see if you're right but as you've described the symptoms spot on it onds very likely. Fingers crossed.

Best bit is that from memory, both caps are available overnight from Amazon's Dunfermline depot for just over a quid (rocker cover oil cap) and fuel tank (about 6 or 7 quid), both Febi parts.


Can't find a fuel cap from Amazon overnight right now, but the above would be a very quick, cheap and easy swap for £1.21
 

stufree

Member
Thanks for that.
I'll order one now but think that I've probably stretched a wire in the loom cable to the MAP sensor. I got a new sensor (on Amazon!) and swapped it when the outside temp was below freezing at start of January. When I turned the ignition on then the ABS lights as well as the EML came on- had no problem with the ABS before the swap so cleaned up the old sensor and put it back which solved the ABS issue but not the usual P0106 air inlet pressure problem. That lasted until yesterday when the Xmas lights etc came on again. The cable was tight and might have stretched more when trying to get it reconnected, a sod of a job with frozen fingers
Had a quick look today at the oil and petrol caps and both look fine. Still got all the lights, engine hunting etc. and can't see any obvious air intake splits or leaks.
VCDS will not talk to the ECU, don't know why as it used to work years ago, but can get some codes off Scantool (not ABS etc). Back to P0106- which will reset but just comes back straight away- as does the P0107 error. The last one never appeared before the MAP sensor swap. Will just leave it until the oil cap arrives, thanks again.
 

Robin_Cox

Member
If you can't get VCDS to speak to the AUA ECU, I think it was @depronman who told me that it was necessary to turn down the baud rate (communication speed) - I have the same issue, where my ODB reader will plug in and work straight away where the laptop with VCDS lite will not (but the same computer and plug combination does speak to my BHC car without issue). Haven't had any recent need to plug in the laptop on that car as all the stuff I've encountered recently have been handled by the ODB reader.
 

audifan

A2OC Donor
Worth checking the dipstick is sealed in the end of the filler tube, the filler tube has no splits and is attached firmly to the block.
 

depronman

Member
Set the baud rate from 9600 to 2400
That used to work years ago when my wifey had a aua engines A2
The edc15 ecu in the tdi’s seems much less picky on being talked to by the computer/vcds
The ecu in the petrols does seem much more picky though

Paul


Sent from my iPhone using Tapatalk
 

stufree

Member
Thanks for all the suggestions and sorry didn't see any of these until now.
Had the baud rate at 9600- which I thought was the lowest on offer? - but will try that later today along with checking the dipstick tube and let you know how things go.
 

Bargepower

Member
Thanks for all the suggestions and sorry didn't see any of these until now.
Had the baud rate at 9600- which I thought was the lowest on offer? - but will try that later today along with checking the dipstick tube and let you know how things go.
My VCDS lite would connect to everything at 9600 - except the climate. Was advised to change the latency (from device manager in Windows) to 1, now it connects to everything perfectly.
 

stufree

Member
Only talks to SCANTOOL at minute, and even then it's a very brief conversation. That's at 9600 - only has the choice of that or 38,400- but I can't see where the baud rate is in VCDS lite? I'll try to change the latency in Windows and see how that goes. Thanks for the suggestion.
The dipstick tube looks fine, can't see any problems there.
 

stufree

Member
hi,thanks for the video link- brought it all back doing this many years ago (had the car for over 14 years). it was aready set to com4 port but tried it on com1 and then 4 again, reduced comms rate to 4800 from 9600 and put latency down to 1 - till will not connect to vcds or vag.com 409. It always talks to scantool with either comms setting but, apart from the p0107 and p0113 faults, no other info on ABS or anything else.
I'll take the battery out and charge it over night but it's not that old. Having said that it took a pounding over the winter so we'll see. Thanks for all the suggestions and breakdown service has lapsed.
 
Top