Multiple Misfires Detected

warp_speed · 15-02-2010,11:25 AM

Hello, I was wondering if someone might have an idea in why I'm getting a multiple misfire problem in my A4 (53 plate) 3.0V6 24k miles on the clock. Fault codes as follows

16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 - Upper Limit Exceeded - Intermittent
16688 - Cylinder 4: Misfire Detected
P0304 - 001 - Upper Limit Exceeded - Intermittent
16689 - Cylinder 5: Misfire Detected
P0305 - 001 - Upper Limit Exceeded - Intermittent
16686 - Cylinder 2: Misfire Detected
P0302 - 001 - Upper Limit Exceeded - Intermittent
16685 - Cylinder 1: Misfire Detected
P0301 - 001 - Upper Limit Exceeded - Intermittent

I recently got the car serviced at an Audi/VW specialist who comes highly recommended, anyway my ECU light flashes on now and again whenever I put my foot down, never had it before until I got my car serviced. The coil packs were replaced before by the previous owner, there's no loss of power or hesitation when the ECU light flashes. Service included a fuel filter change and fuel system clean.

Has anyone got any ideas in what this might be?

Thanks

crichten · 15-02-2010,01:58 PM

Change your HT plugs.

If you are with the RAC/AA give them a call tell them the car is misfiring and they should be able to come do a full diag.

But I had the same thing and it was my HT plug.
About £24-£30 a piece.

**Crasher** · 15-02-2010,02:09 PM

After plugs have been replaced on cars with coil packs it is common for them to fail but that is four failures although not continuous which is odd. I would have six new coil packs fitted and see how it goes.

warp_speed · 15-02-2010,02:11 PM

Originally Posted by crichten

Change your HT plugs.

If you are with the RAC/AA give them a call tell them the car is misfiring and they should be able to come do a full diag.

But I had the same thing and it was my HT plug.
About £24-£30 a piece.

HT plug, I guess you mean the coil on plug/coil packs? Is it typical for them all to go at the one time?

warp_speed · 15-02-2010,02:14 PM

Originally Posted by Crasher

After plugs have been replaced on cars with coil packs it is common for them to fail but that is four failures although not continuous which is odd. I would have six new coil packs fitted and see how it goes.

Plugs have not been changed, didn't think it was worth spending £110 to get a set of spark plugs changed, when I could get the bits from Audi myself and change them.

**Crasher** · 15-02-2010,02:26 PM

Fit new plugs and coil packs then

**Crasher** · 15-02-2010,02:28 PM

What is the engine type code? I had this happen after an oil change and it turned out to be the VVT actuator on one bank but yours may not have the system so I will check.

warp_speed · 15-02-2010,02:50 PM

Originally Posted by Crasher

What is the engine type code? I had this happen after an oil change and it turned out to be the VVT actuator on one bank but yours may not have the system so I will check.

I think its a AER or AEH engine code, can't remember off hand but it starts with an A, 3.0V6 petrol 53 plate

**Crasher** · 15-02-2010,03:41 PM

PM me your reg number.

warp_speed · 22-03-2010,12:08 PM

Well, I changed my plugs and coils, all was fine and dandy until the same error popped up again, can't believe 5 of my new coils are duff, does anyone have any other idea in whats causing this issue, thanks