S3 BAM - FAULT CODE P1297 - Intermittent Misfire at 2000RPM

[ghill]

My car has developed an intermittent misfire at exactly 2000rpm, sometimes when car is started from cold, sometimes after a motorway run when pulling up to first roundabout after slip road. Can also run for 1/2 an hour with no misfire. Completely random as far as I can tell.

Its a 52 reg BAM engine S3 with 58K on the clock.

Misfire can be in any gear but always at exactly 2000rpm! When its playing up get the rev counter to 2000 and it will do it every time but then will clear for a while.

Over past 4 weeks I have changed:

- New OEM Thermostat and temp sender (temp gauge was at 60degrees max) this is now fixed and bang on 90 again.
- 4 brand new OEM coilpacks
- New OEM air flow mass meter
- New OEM divertor valve
- New OEM standard air filter

Fault code after misfire is 'P1297 - connection charger - throttle valve pressure drop'

Car is fine under load, plenty of boost and no misfire. Just this nasty bump at 2000rpm when it chugs along like an old tractor and nearly puts you and passenger through the windscreen! As soon as the rev counter gets to 2100rpm it clears and revs up to 7000 if you want.

No ECU warning light in the dash at all when misfiring.

Car is remapped to approx 270 but now otherwise standard.

Any help would be massively appreciated, not sure where to go next and recently burnt lots of cash on this and still no better and missing having an otherwise great car running as it should.

Next thoughts are N249 (but ran with divertor unplugged and fault still there)

Thanks in advance

 

[finesse]

Check your coilpack wiring, when was your last spark plug change?

http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/87019-what-look-if-you-keep-blowing-coils.html

 

[ghill]

Spark plugs not been changed for a few years - I'll go there next.

Coilpack wiring not been fully explored but looks ok from the front. I'll take a better look tomorrow.

I had ruled those out as its fine under load but maybe I've been missing the obvious there.

THANKS

 

[finesse]

plugs

 

[ghill]

OK - I changed the plugs for Audi OEM / NGK plugs and unfortunately the problem is still there.

I also looked at the coilpack wiring while I was at it which looks fine.

Not sure where to go next, my list over last month is now:

- New OEM Thermostat and temp sender (temp gauge was at 60degrees max) this is now fixed and bang on 90 again.
- 4 brand new OEM coilpacks
- New OEM air flow mass meter
- New OEM divertor valve
- New OEM standard air filter
- 4 New OEM / NGK sparkplugs

Still getting:

P1297 - fault as described above with misfire at 2000rpm. (most awkward revs it could be at as it's when you're pulling off at roundabouts etc!)

Any further thoughts would be much appreciated.

Thanks

 

[s3gazz]

Im sure it will be a boost leak, can you get it pressure tested or spray some fuel injection cleaner around all hoses especially under the inlet to see if the engine changes note......

 

[ghill]

Cheers - I'll get onto that and see what I can find.

Wouldn't a boost leak be worse at high load though? It revs straight through with no hesitation once it's passed 2000rpm!!

I'll start searching for leaks next - thanks for the advice

Has anyone had problems with N249 with similar symptoms to this? That's one of the things Ross Tech points to with this code.

 

[finesse]

Is this error returning each time you clear it?

 

[ghill]

Yep - clear the code, once it's misfired the error code is back. No others just P1297.

 

[finesse]

ah right, you got the dreaded error which can not be shaken


17705 the Saga is over (well for me anyway!!!) - uk-mkivs

unless your mentioning the wrong code

17705/P1297/004759 - Pressure Drop between Turbo and Throttle Valve (check D.V.!)

Possible Symptoms

• Malfunction Indicator Light (MIL) ON
• Power Loss

Possible Causes

• Leaking Hoses and/or Pipes between Components
• Boost Pressure Control Valve (N249) faulty
• Diverter Valve faulty
• Throttle Body dirty

Possible Solutions

• Check Hoses and Pipes between Components
• Check / Replace Boost Pressure Control Valve (N249)
• Check / Replace Diverter Valve
• Check / Clean Throttle Body
  • Perform Throttle Body Alignment

Special Notes

• Did anyone install an extra (wrong) dump valve?
• When found in the NAR 2.0T (BPY) check RVUTB: 01-09-03 or 2018919 for updated Crankcase Breather Valve
  • If the breather valve is faulty, full engine vacuum is typically found when removing the oil cap at idle.

 

[ghill]

Thanks a lot for that link - definately feels like it's the right area and I need to check more pipework next. Some of the pipes around the N249 feel very soft. Particularly the one going into the flying saucer thingy. (cylinder block pressure reg valve i think????)

Do you think this pipe sucking flat would cause a prob? I suppose any soggy pipe is not going to help but not sure about that one as its the end of the line and not sucking air in is it?

With the code, it is P1297 - but the word description is a bit different to the one you got there, mine says 'Connection charger - throttle valve pressure drop'.

Think I'll rule N249 out by sorting that next as I've sorted the DV and checked the throttle body today which is clean.

TA

 

[ghill]

Thought I'd add, on a positive note, once out of misfire territory the car is flying with all the new electrical bits! The old Air Mass meter, while not the direct cause of the misfire was giving bumpy power and the plugs had obviously been in there some time so it's not all bad if upgrading bits while searching for the cause of this prob!

Looking forward to spending the money on performance upgrades rather than fixes again Tho'!