RPM at idle increasing to 1000rpm. Also some VCDS errors codes.... help please.

[ZeeSaffa]

Hi all,

I'm looking for some help please.

I'll summarize the issues from the beginning:

April - Coolant sensor warning light starts coming on when starting car. Didn't notice any other problems so ignoring until I get time to look into it.

A few weeks ago - Started car after 2 week holiday. Battery almost flat but JUST about started.
Battery is a good quality Silverline Varta as recommended on this forum. I replaced it about 2 years ago.
- Soon after the flat battery incident - when idling the revs would go up from 750rpm (normal) --> 1000rpm and hover there. It's been doing this constantly ever since.

Last weekend - I plugged my VCDS in and found a whole bunch of error codes I couldn't make sense of. Need to book it in for fix up.

Monday - Driving to work - engine management light comes on car start "stuttering". Took it straight to independant VAG specialist.

The VAG chaps were very good to be fair. They found issues with both the coolant temp sensor and the fuel temp sensor. They replaced both (for a very reasonable price I should add) - took it for a spin and everything felt good.

The only issue was that this error code remained:

-------------------------------------------------------------------------------
Address 01: Engine Labels: 03G-906-016-BKD.lbl
Part No SW: 03G 906 016 FF HW: 028 101 190 5
Component: R4 2,0L EDC G000SG 7364
Revision: 12345678 Serial number: AUX7Z0E6FN50O1
Coding: 0000072
Shop #: WSC 06314 000 00000
VCID: 6CDDE42D4FDBBB7E57F-8039
1 Fault Found:
18051 - Please check DTC Memory of Electric Load Controller
P1643 - 000 -
Freeze Frame:
RPM: 1008 /min
Torque: 28.0 Nm
Speed: 0.0 km/h
Load: 0.0 %
Voltage: 13.91 V
Bin. Bits: 00101000
Torque: 132.0 Nm
Bin. Bits: 1 01 0
Readiness: 0 0 0 0 0
-------------------------------------------------------------------------------

They checked all other control modules and couldn't find a fault - so this must be a false warning.
They suggested I take it to an auto-electrician.

I picked it up yesterday afternoon - took it for a drive myself and all was good.
Then took it for another drive last night and unfortunately - the idling issue is back

Plugged in VCDS and in addition to the above error code - I also have this one:

-------------------------------------------------------------------------------
Address 09: Cent. Elect. Labels: 8P0-907-279-23-H.lbl
Part No SW: 8P0 907 279 F HW: 8P0 907 279 F
Component: Bordnetz-SG H36 1201
Revision: 00H36000 Serial number: 00000002051953
Coding: 01884F06A214100000000000000000000008FE175C0100
Shop #: WSC 06314 000 08192
VCID: 4085609D13D38F1EDB7-8015
Subsystem 1 - Part No: 8P2 955 119 B Labels: 1KX-955-119.CLB
Component: Wischer AU350 H01 0130
Coding: 00062736
Shop #: WSC 06314
1 Fault Found:
01598 - Drive Battery Voltage
000 - - - Intermittent
Freeze Frame:
Fault Status: 00100000
Fault Priority: 2
Fault Frequency: 5
Reset counter: 245
Mileage: 134232 km
Time Indication: 0
Date: 2014.06.25
Time: 14:14:00
Freeze Frame:
ON
Voltage: 13.70 V
ON
ON
OFF
OFF
OFF

-------------------------------------------------------------------------------

Does anyone have any thoughts on what this could be please?

I should mention that I checked my battery with a multimeter:

When car is running: 13.45v
Car off: 12.3v

Thanks in advance

 

[LEE69]

It raising to 1000 is the dpf self regenerating.
coolant sensor may need the prongs scraping in the coolant bottle, as long as you are not loosing coolant.

Charge the battery up, but i guess it's on it's way out should last more than 2 weeks parked up

 

[ZeeSaffa]

Thanks Lee

The coolant bottle was replaced on Tuesday - sensor and all.

I've had some good runs to / from work which should be sufficient to charge the battery... am I right?

 

[LEE69]

It might be but if the battery has a dead cell, it won't be.

 

[ZeeSaffa]

Yep... good point!
Any idea if there is a simple method that I can tell if the battery has a dead cell?
A quick Google tells me its best to take it to an auto shop... bit of a pain. I'll have to find one willing to test it for me.

 

[LEE69]

kwik fit halfords ats can all test it for you

 

[ZeeSaffa]

kwik fit halfords ats can all test it for you

Good stuff... will get it done tomorrow. Thanks for your help & advice

 

[LEE69]

Also check out the prices before you buy ecp on ebay was the cheapest for me at the time.

 

[SmithyAG]

The first copy and paste part of the VCDS scan shows its a BKD engine doesn't it?
I didn't think they fitted a DPF to anything with a BKD engine?

If i'm right then the revs rising and dropping are not a regen and you need to diagnose the issue again.

If i'm wrong, well just ignore me!

 

[LEE69]

Possibly correct, not massively up on the codes and what had what yet, was just going by what mine did.

 

[SmithyAG]

Possibly correct, not massively up on the codes and what had what yet, was just going by what mine did.

I believe the BMM engine (140bhp) had a dpf and so did the BMN (170bhp), but the BKD didn't.

I seem to remember a thread about revs rising and it was down to the alternator being on it's last legs and as the car recognised it wasn't putting out the correct amps at idle it had raised the idle revs to compensate.

 

[ZeeSaffa]

Yeah, I did find another thread about the BKD being without DPF.
I'll look to replace the battery... £70 is worth the punt.
If that fails... then will consider replacing alternator.

Thanks... again

 

[SmithyAG]

If you're replacing the battery is a silver varta not still under warranty? Just a thought.

Even if the alternator does need replacing, although the part is not cheap brand new, its not a particularly difficult job.

 

[ZeeSaffa]

If you're replacing the battery is a silver varta not still under warranty? Just a thought.

I also thought that... but I can't find the email for the transaction... can't even remember which online retailer I bought it from!!

I just had it tested at National Tyres (the chap at ATS was too busy) - results:

Battery test: 12.56V
Starter test: 10.80V
Charging Test: 13.43V

Result: Good Battery.

The chap said that if it had a dodgy cell then their tests might not pick it up. Not sure where else to go with this now... short of shelling out for a proper auto-electrician.

Any ideas?

 

[ZeeSaffa]

**RESOLVED**

Firstly, went to ATS over the weekend and they tested the battery. They said all power tests looked good but there was a note just saying "RECHARGE".

So, the car went in yesterday for a service (had it booked anyway) - and asked them to sort out the noisy belt. Turns out the noise was due to the belt slipping because of a seized alternator pulley... which probably resulted in the poor charge to the battery - which meant it wasn't charging the battery as expected and caused it to raise the revs to try to compensate.

I have to give credit to http://www.colingunning.co.uk/ (VW & Audi Specialists - Hertford) who did a great job at fixing the issue, great customer service and are very reasonable price-wise!

I swear it even feels smoother and more responsive now after having the issue fixed and a major service. Chuffed

 

[LEE69]

Glad it's sorted

 

[ZeeSaffa]

Yep - me too

Thanks again for the suggestions!