A2 2001 1.4 se petrol cutting out when warm

Starts perfect when cold but when it heats up it cuts out, try to start it again and takes 5 mins to start, had it in a garage plugged into a computer and a fault came up with something to do with the exhaust gas recycling, mechanic cleared the fault and took it a run and left it idling for 30 mins, brought it back to me telling me this was all he could find so I thought it was sorted, broke down on Sunday there with same problem, also the alarm will come on randomly when the car is locked I'm not sure if they are related problems I'm just not sure and car is driving me nuts.
 
Hi i can give you a few pointers but no sure fix----the 1.4 often thrown EGR valve errors (exhaust gas recycling valve). Its a vacuum driven valve designed to hep with emissions but often can get blocked with grunge from a mixture of exhaust soot and fuel/oil sludge. So possibly get that inspected or exchanged. The other cause could be crank sensor as they often play up when hot. The alarm sounds like it is the signs of the CCU starting to fail---one thing to try is to disconnect the battery for 30 mins it may reset its internals.
Hope that helps mike
 
Starts perfect when cold but when it heats up it cuts out, try to start it again and takes 5 mins to start, had it in a garage plugged into a computer and a fault came up with something to do with the exhaust gas recycling, mechanic cleared the fault and took it a run and left it idling for 30 mins, brought it back to me telling me this was all he could find so I thought it was sorted, broke down on Sunday there with same problem, also the alarm will come on randomly when the car is locked I'm not sure if they are related problems I'm just not sure and car is driving me nuts.


It would be worth changing the temperature sender, they often fail and you don't see any sign of the failure, it fails on the part that sends the temperature to the ECU, not the temperature gauge and so it can think that the car is cold when it is hot and that makes it difficult to start.

As for the alarm, check that the front flap is securely closed, that often triggers the alarm.
But if you also have problems with windows not working as they should and/or remote locking, then the CCCU may be on the way out.

Steve B
 
Cheers for the replies, I have changed the coolant temp sensor and the problem was still there, it has got worse since I posted this now the car will start but it will cut out as soon as you stop revving the engine, does anyone have a photo of the pipe and where it is that may be needing cleaned on the egr?
Cheers again folks,
Chris
 
Hello, related to my problem with the rough idle and hesitation on throttle, I think I found the problem. In group 62 the last field is not as it should be. I know that it should be half of the third field but in my case it has the same value. Even after readaptation it will stay at the same value. Can it be that my TB is faulty or the pedal sensor??? How can I test this?? Or do I have to buy a new TB.
 

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Hello, related to my problem with the rough idle and hesitation on throttle, I think I found the problem. In group 62 the last field is not as it should be. I know that it should be half of the third field but in my case it has the same value. Even after readaptation it will stay at the same value. Can it be that my TB is faulty or the pedal sensor??? How can I test this?? Or do I have to buy a new TB.

I wouldn't jump to conclusions here. If your throttle body needs cleaning, your vagcom readings will be off. If you have rough idle too, this is indicative of a dirty throttle body. Carry out a thorough clean of it and you should find this helps your idle and other issues too. Read through the link I sent previously, the entire thread needs to be read before doing a clean as there are lots of tips and info in various replies. It's quite an easy job, but take your time to clean it properly and replace the metal gasket with a genuine one from VW or Audi (it's cheap). The most expensive part of the job is buying carb cleaner. If you're not up to the challenge or don't have time/inclination get a garage to do it - shouldn't cost a lot.
 
Also, don't reset the throttle body UNLESS it has been cleaned, otherwise you'll find all sorts of errors are thrown up.
 
I've cleaned the TB very good before, many times, changed all the sensors that could induce this rough idle, checked for vacuum leaks, changed the fuel pump, changed the EGR, took out the intake, checked the compression, new sparks, coil and spark plugs.... you name it ---same result. I see 3 options here---bad TB, faulty ECU or maybe a bad connection, voltage leak.....
 
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I've cleaned the TB very good before, many times, changed all the sensors that could induce this rough idle, checked for vacuum leaks, changed the fuel pump, changed the EGR, took out the intake, checked the compression, new sparks, coil and spark plugs.... you name it ---same result. I see 3 options here---bad TB, faulty ECU or maybe a bad connection, voltage leak.....

Just to check, are you "madalina" the same person as "Chris Harvey", who started this thread? Otherwise it's hard to know what's been said and done already and if you're not then you should really start a new thread about your problem so there's no confusion.

If you're experiencing a cutting out of the engine or a hard restart when warm, like the original thread creator, then you should first look at the coolant temperature sensor (which Chris said he'd changed). If there's a rough idle that's a separate issue and I'd personally start by looking at cleaning the throttle body. If you say you've done everything else anyway, then giving it another clean might be necessary, depending on how long ago you did it and how thoroughly. Also, after the throttle clean you need to reset/recalibrate it and not doing so properly would give odd behaviour.

You mention bad connection - this is another possibility, many people begin by checking the earthing points in the car that have been known to corrode. Search the forum to find out more about this.
 
No, I am not the same person and I don't have the same symptoms as he. My wife's car starts with no problem and doesn't stops after warming. Sometimes the idle goes up to about 800 with Ac on, but if I push on the Econ it will go again down to that rough idle at about 650. In both ways it will stall in first or reverse. If I take out all the electric consumers the idle slightly decrease and you can hear the engine going bad.Otherwise the cars pulls up very good, and revs nice to red if wanted. Can itbe an electrical problem?? I have found corrosion in the ecu compartment and I had to fix 2 connections on one plug. Can those to wires made something go wrong?? Where can I find a wiring diagram for this car?? I want to check those wires and see wher they go....I think I put a picture last year with that plug damaged
 
Can this be the problem??? To wires from this plug were totally broken. I got it fixed but maybe there's also damage on the other side. Where does the wires goes from this plug???
 

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To the original thread starter.

I had the same sort of issues and the TB was totally coked up with gunge. To clean it you properly it needs to come off and you therefore need the gasket kit, which is not expensive from Audi. Hopefully someone can chime in with the part number. Get some carb cleaner and lots of rags and go to town on it, being careful not to damage the flap mechanism whilst cleaning. Also clean out the EGR pipes that are close to that location depending on the build up you see and and you should be good to go. After rebuilding use VAGCOM to perform a TB reset and don't expect it to go very well for a while. I completed the TB reset and the car wouldn't even start that evening, left it overnight and the next morning it would start but wasn't perfect, over the next couple of days things got better. Well worth putting the time in as now runs much better.
 
I took it off several times, 4 or 5 times and when I checked the Intake manifold. Every time I cleaned it with carb cleaner and did the TBA via VagCom. I don't get any error when recalibrating but now, recently I found out that in group 62 field 1 and field 2 must have together 100% and the 4 field muls be half off the third field. This let's me to think that is something wrong with the. TB, wires or ECU. I admit that I used the same gaskets but I don't think this will improve the idle very much. I used carb cleaner on the TB to check for leaks and I didn't notice any difference.
 

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I've downloaded the service manual from eManualOnline and found out that this 17 brown pin connector with corrosion on it and to broken wires is between the TB, the accelerator pedal and the ECU. It's clear to me that at some point when corrosion occur something went wrong with the TB, acc pedal or ECU. I will search the connection on the pedal for corrosion and check the wires. If everything is ok then I'll start with a TB swap. Both wires that were broken are between the TB and the acc pedal---this is why I get a wrong value in fields 3 and 4 in group 62. Everything is clear now, i just have to dig up more and find the source.
 
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I have no idea. I bought the car with the fault 01314 engine control module and found the 2 wires broken on the connector T17. After fixing them I was able to talk with the ECU and I thought that the problem was solved. I've begin to change sensors,sparks, plugs with no improvment so I went back to the source....group 62 was the big bang :)) I don't give up so easily. I'm pretty sure it has to be something between TB and acc pedal----tomorrow is the big day
 
Excellent. No other damage to panels or water ingress through grommets in the bulkhead? It's a new one on me, every day is a school day.
 
I've checked everything, voltage, resistance and the continuity between TB, acc pedal and the ECU. Everything is in order except the resistance at the TB. Between pin 3 and 5 at the TB or pin 117 and pin 118 at the ECU plug it should be 3-200 omhs. I get only 2.3-2.4. I don't have another good TB to check resistance at pins 3 and 5, but it says clear that ''If specification is not obtain ----replace the throttle valve control J338''
 

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