Epc warning light on

[nomadx38]

Look in the end it would probably be better to get a VAGCOM and check it yourself as VW charge an average of 150+ p/h for diagnostic work.

Don't be too concerned about all the lights on the dash - this is caused becuase all the systems are linked. The engine has a fault which will automatically disable the ESP and braking module (which also controles the TPMS). chances are its a very small thing like a coil pack or ignition lead.

[steveyoshi]

Hi all... I would be interested in finding out a bit more about all of this.

Had a flash or 6 from the EPC light for the last week or so... and every so often a rough idle... normally stationary only and in gear, foot on brake... would clear itself back in neutral or as I pulled away.

That is now becoming a miss from 1500 to 3000rpm.

Seems to feel like a coil or a plug.

Now... this morning... not a cold day.

1min from a cold start... flasging red temp light... got coolant !

Stop... restart... all gone.

Then... 5 mins later... terrible miss and flashing epc light... hard to drive at all.

Pull over... neutral... miss appears better. Stop engine... restart and then all clear again.

Get to work... check coolant again... the same... all good... a little low but looks good... no oil either.

4 hours later... restart car... run for a few minutes... no lights .. no rough idle or miss... just at idle or at 2500rpm... whilst in P though.

Any thoughts... could a coil do all this ?
Melted plug ?
Hole in piston - surely not ??
Head Gasket gone or cracked head - surely not ??

Polo 13
Stage 2
IC, Exh, and Filter.
68k

[Umai Naa!!]

You need to scan it and go from there.

The reason it comes good again after you restart it is becauce the ECU cuts fuel and spark to a cylinder where the missfire is detected, until it detects it again, which is usually under load whilst driving.

Once you know which cylinder, or cylinders it's logging missfire faults on, you'll be able to narrow it down.

[steveyoshi]

Makes perfect sense... thanks.

Hope to scan soon... seems fine again when I tried it at the end of lunch.

[Umai Naa!!]

It'll still have the codes stored in the ECU.

[steveyoshi]

Yes... I know that, apparently you cant clear codes, they are either active or historic.

Do you have any experience with an ELM BT OBDII Dongle and an Android App, would that show the miss fire codes ?

[steveyoshi]

Ok... now I can see this becoming a larger problem.

Flashing Red Temp Light was intermittent... but now pretty much on all the time yesterday... so I topped up the Expansion Tank with Distilled water, probably only used about 300ml.

It seems that when the engine is cold, it should be between the min and max. So I filled up to the Low level and will check again when it is warm. Haven't used the car since the top up last night. The temp gauge has not gone any higher than normal.

However I think this seems that I may have a head gasket or a cracked head issue, with coolant getting into the Combustion Chamber... causing the miss (first issue a couple of weeks and now getting worse)... so may not be a Coil or Plug issue.

Coolant shouldn't really go anywhere without a leak... and if there appears to be no leak... it must be being burnt somewhere.

68,000kms and I have already had 3 mods on oil burning, replaced a Mechatronics... now a head potentially... what a piece of **** lemon.

What does anyone think ?

[Umai Naa!!]

If it were a headgasket, you'd be seeing evidence of it in either the coolant or engine oil.

[steveyoshi]

That's what I thought too... so I checked... oil is not cloudy nor is there any oil bubbles in the coolant.

But I was thinking that coolant was only getting into the combustion chamber and being burnt... not sure!!

[Umai Naa!!]

If it were from the water jacket to the combustion chamber, the system would over-pressurise and the coolant would be pushed back out the overflow port on the expansion bottle.