A4, 1.9 tdi, AWX, PD, 2002 - Poor idlle

[eugene walsh]

hello we have a 2002 a4 1.9 tdi pd eng code awx  and it is ticking over very lumpy but as soon as you rise the revs it is ok it started  with a while back but it was intermittent now its constant we replaced the injectors with one we knew were good no joy the customer said he put five pounds of petrol by mistake so he filled it on up with diesel and the Idle was great but when it was back to only diesel it was poor i have checked egr/airflow /timing all ok  starting to do my head in and we have another one with the same problem coming in next week so i am hoping someone knows the cure thanks :eug

[eugene walsh]

thanks for the reply the crank sensor goes into the block and picks up of the web of the crank so there wont be any problems there this car will run perfect if there is a little drop of petrol in with the diesel as the customer but some in by mistake  and it run great till it was all diesel i said it might of been that the problem might have temp fixed its self so he try ed putting petrol in again and the car runs perfect. i heard that there is a flash download for this problem but our local Audi dealer is not the most helpfull and want to book the car in and we all know what that means.thanks :eug

[guerrra]

hi do you have vag com?

if so chek the sicro angle on measure blocks and see if it is 0 or 0.5 or so


if you get a hight value retard the timing on the camshaft a bit and see if it goes beter hapen to me a fwe times..
guerra

[The Specialist]

Correct me if I'm wrong but did the fault generate after the PETROL was put into the vehicle? Might be worth changing the fuel filter. Have had a A6 which had similar symptoms as described. The engine would run erratically at idle speed. If the vehicle accelerated and on overrun between 1,800 and 2,100 rpm, the vehicle jerked and the accelerator response was delayed. At high revs over 3,000 rpm there was no fault .

The ventilation on the solenoid valve for exhaust gas recirculation gets dirty. As a result, the vacuum on the exhaust gas return valve cannot be reduced in time. Therefore the exhaust gas return valve stays open longer, a large exhaust gas rate is returned and the engine starts to run erratically.


Webby

[eugene walsh]

thanks guerra i will check that one out i had seen that on another forum i think it was from you so i will let you know as i now know it had a belt replacement a while back. webby thanks also. this problem was not a result from putting petrol in but if you do but petrol in it runs great i have also blocked off the egr valve still no difference changed filter twice and at the start changed fuel. last night i even changed the tandem pump just to rule it out thanks again everyone for your help and i will let you know the outcome :eug

[eugene walsh]

hello guerra thanks you were spot on it worked a treat i don't think i would have ever went for that as if all the timing pins fitted  you would think the ecu would adjust for the rest but i am happy as that is two problem cars away and paid for. thanks for the help everyone :eug