'95 A6 intermittent start failure

[sumbuddy]

it goes and goes and then..

it doesn't.

The funny/mad/infuriating thing is that if I mess about with the ecus under the bonnet near the dashboard she will start.

But those things deal with the sunroof, rear wiper, electric windows and radio and are not (allegedly) anything to do with the engine electrics.

Any help gratefully accepted as it sometimes leaves my gf and the children in tesco carpark with no start and glum looks.

[Teutonic_Tamer]

Any help gratefully accepted as it sometimes leaves my gf and the children in tesco carpark with no start and glum looks.

Ohh, its' gotta be worth leaving it, just to see the look of thunder on SWMBOs face :D . You got her well trained to go Tesco without you ;) .



it goes and goes and then..

it doesn't.

The funny/mad/infuriating thing is that if I mess about with the ecus under the bonnet near the dashboard she will start.

But those things deal with the sunroof, rear wiper, electric windows and radio and are not (allegedly) anything to do with the engine electrics.

OK, OK:
- battery: good voltage, clean and tight terminals?
- earth lead: good condition, clean and tight chassis connections?
- starter motor: main lead clean and tight, possibly a sticking solenoid?

It does sound as though you have some loose or poor quality (corroded) connections. Get a can of silicon grease spray (not WD40, although it will do for emergencies), disconnect all relevent terminals, look for corrosion, give em a quick spray, reconnect.

CAUTION: don't disconnect anything with the ignition on, or it will store fault codes!

HTH, rgds

[sumbuddy]

Ok thanks for the swift reply Sean!

GF can't wait to go to Tesco 'cos thats the only place I let her drive.

Righty ho then.

Battery on second winter has plenty plenty go. Clean, tight terminals.
Earth strap connections ditto.
Starter leads ditto.

I have just gone around the engine bay again and checked every lead (complicated slightly by all the sensor cables on the gas system) and they all seem fine.

The only reason I checked the area at rear of engine compartment was because there is a lot of clicking going on there if the engine doesn't start - quiet otherwise (the engine head was replaced a couple years ago and is v quiet)

I will go around again now because the engine just got lumpy at 1200 - 1500 revs since I disturbed the leads/cables/terminals.

[Teutonic_Tamer]

Ok thanks for the swift reply Sean!

No worries, you're welcome.


GF can't wait to go to Tesco 'cos thats the only place I let her drive.

:D




snippage:
there is a lot of clicking going on there if the engine doesn't start

:arms: Starter motor toasted. Either high internal resistance, knackered brushes, seized through lack or lubricant, or internal current leakage.

But it also could be your battery. If the starter motor has been placing too great a load on the battery, it could have given up the will to provide the necessary juice. What make, model and Ah is the battery??

Might be worth getting an Auto Sparky to check for current drain during starter cranking - just to rule in/out either component!

HTH, rgds

[salty]

it goes and goes and then..

it doesn't.

The funny/mad/infuriating thing is that if I mess about with the ecus under the bonnet near the dashboard she will start.

But those things deal with the sunroof, rear wiper, electric windows and radio and are not (allegedly) anything to do with the engine electrics.

Any help gratefully accepted as it sometimes leaves my gf and the children in tesco carpark with no start and glum looks.
MY LACK OF ELECTRICS STARTED LIKE THIS .JUST IN CASE REMOVE THE TRIM ABOVE THE DRIVERS FEET AND YOU WILL SEE A ROW OF RELAYS UNDER WHICH THERE ARE SOME 10MM SPANNER SIZED NUTS SPRAY WITH WD40 AND TIGHTEN THIS CURED ALL MY ELECTRICAL PROBLEMS
SALTY

[nonstarter]

sumbuddy - just wondering if you'd got to the bottom of the problem?

I have a similar problem...

1997 Audi A6 with intermittent electrical problem meaning the car runs fine for ages and then completely randomly it won't start.

We used up all our lives with the roadside recovery company with this problem and each time the mechanic spent an hour testing stuff and narrowed it down to no current getting to the starter motor.

Unfortunately having been towed back home, next time I tried to start the car it worked perfectly.

This leaves me in complete limbo with an unreliable car.

A diagnostic check showed nothing.

I'd be really grateful for any suggestions/pointers etc.

Thanks.

[salty]

SINCE TIGHTENING ALL THE RELAY CONNECTIONS I HAVE HAD NO MORE TROUBLE:Blush:

[nonstarter]

Thanks Salty I'll give that a try.

My problems seemed to coincide with the time a new stereo was wired in, and I was wondering whether there was a connection.