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Discussion Starter #1
Hi everyone

I have a 1993 Coupe 2.0 16v that I have recently encountered a prob with. It has covered 168K and until last week ran perfectly. Since owning the car since last June it has always started on the button what ever the ambient or engine temp.

Now it is very tempermental, sometimes starting up straight away, sometimes cranking over for 20 secs before finally spluttering into life on maybe 2, then 3 cylinders before running right, usualy revving it up a couple of times sorts it out, it will then run perfectly once started and return good mpg.

The hardest time to start is usually if it is left to stand for a couple of hours after a run. To be honest sometimes my heart sinks as it doesnt sound like it is going to fire at all - allthough it always has (so far!)

The local garage has run a scanner on the ECU - no fault codes occur, I have changed the plugs which hasnt made a difference. The emissions have also been checked.

I am thinking maybe the Coolant temp sensor is up the creek. I am struggling to find info on the engine as haynes manual doesnt cover the engine. Which senso is it? Is there any tech drawings ,photos availible for this engine?

Can anyone help or advise? Its driving me mad!

many thanks in advance
 

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Might be the Hall Sender. A damaged one will create starting problems. Worth checking.

The coolant temp sensor is less likely to create starting problems, but the fuel temperature sensor might do that, since it influences the injection timing.
 

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I would be inclined to take the distributor cap off and have a look inside to see that the contacts have not furred up. The symptom of firing on 2 then 3 then all 4 seem to suggest something electrical rather than fuelling.

Good luck
 

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Discussion Starter #6
Cheers for the response guys.

I have now:

Changed Plugs

Fitted brand new Dizzy cap (old one was very worn)

Fitted new temperature sender (one on back of head)

The fault is still there. I cant get my head round why the problem is much worse when the car has stood for a bit after a run. Makes me think the prob is temperature related (a different sensor perhaps?) The car does misfire initially though for the first few seconds after a prelonged cranking. If it fires instantly (which it does in the morning) there is no misfire.

I think I will check the hall sender and the coil next. Any know the correct precedures for checking this parts or is it a specialist electricians job?

Many thanks in advance!
 

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Discussion Starter #7
Thanks for all the ideas lads!

After aquiring the correct Haynes manual and checking various things I am admiting defeat and have booked it into an auto electricians on fri.

Im convinced that the bread and butter components are fine on the engine now so From other research I ve done I now reckon it is a fueling issue. I am thinking that fuel pressure is being lost either at the pump, regulator or even at the injectors.

1 Engine cold - Cold start enrichment occurs - starting no probs

2 Engine hot - Again, fuel is there ready to start the engine

3 Engine warm ( stood for 30 - 60 mins after decent run), Fuel pressure has gradualy been lost through leak point, resulting in lots of cranking (no fuel smell) and spluttering to life.

Well I will see what the garage comes up with anyway.

Will post the cure -- it may help others out!
 

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What you said about it seems to happen most when you try and start it after it's been driven and then sitting for a little while, sounds like the injectors might be leaking.

The fuel pressure is the highest just after you stop and would start leaking slowly. If the car sits overnight, some of this might evaporate and so it wouldn't be as bad.

My Dad designs injectors and it's one of the biggest problems he had is just like yours. Hard to start after it's just been driven.

Additionally, it seems it was a known problem in the 90-92 models.

http://auto.consumerguide.com/Auto/Used/re...iewreliability/

Rough idle: The original O-rings on the fuel injectors will harden and leak causing idle problems. New seals are made of Viton rubber.

Good luck
 

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Discussion Starter #9
Well I ve had the car back for a couple of days and it seems to have been fixed. Garage tested for vacuum leaks, fuel pressure, fuel injection fault codes etc... Couldn t find any probs.
The only thing they did was find the airflow meter flap to be out of adjustment. They readjusted it and everything seems to be fine!
Wish I had booked it in the first place now - however the parts I replaced all would have let me down in the end.
I will see how it goes! :liebe011:
 
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