Alright chaps, not getting any joy with replies in diagnostics section so thought I'd try here...

 

My mk1 Octy vrs started with a running issue. Car is stage 1 initially was a severe loss of power and hesitancy sort of misfire but felt fuely rather than sparky.  Was holding back then taking off etc.

 

 

Tried a run with MAF unplugged, no difference in fact worse.  Tried a spare set of plugs, now this improved the running but the issue is still there and at times just feels generally down on power.  No codes thrown at this point.

 

However, EPC and TC light then came on and ALL power went.  Turned off and on again power returned albeit with the same running issue.  This did give me a code though:

17743 engine torque monitor 2 control limit exceeded

P1335 35-10 intermittent

 

I also had 01314 ABS fault but I think that was from unplugging MAF as TCL came on.

 

I then measured blocks 002 and the intake air mass gave me 170 g/s at 5880 rpm, which extrapolates to around 210bhp about right, so can rule out MAF?

 

I then measured 032 for fuel trim (unfortunately I'd cleared the code, didn't realise it would help if I didn't) so ADD mixture unsurprisingly stayed at 0%, Eventually got a reading from Multi mixture of -1.6%.  Is that normal or does that mean it is too rich?  Would explain the feeling like injection is being held back. 

 

Looked at possible causes on ross tech for 17743 code:

Even though unplugging MAF made no difference I have a spare I can try although I'm not sure that one is too good.

My CTS is genuine and went in a few months ago so that would surprise me, I do have the spare non-gen one I took out I could try, which was working when on car.

Air filter is pipercross panel so should be ok.

According to ross tech that basically leaves possible causes of leak in intake after MAF and intake air temp sensor to explore.

 

Situation now is I tried resetting throttle body running was less hesitant and smooth for a good while this morning after this, thought I'd go a little further to make sure then slight hesitancy returned, I didn't get the power cut, but the traction control light randomly came on.  Got home, I'm starting to think brake pedal switch problems, all brake lights fine, but ABS light started flashing at me.  Strange thing was when I pressed brake pedal to test lights the traction control light went off.  During this run add mixture remained at 0.6% and multi went up to -7%, is that normal or too rich? Both are within 10%

 

To be honest I'm confused and frustrated and I've got a list of a million things it could be, or could it be that it's 'just' my ecu and that itself cannot diagnose properly hence the running and confusing codes.  I'm not even sure the 17743 code is much to go on and now I have the 01314 code back for check dtc memory engine control module, which to me doesn't mean a great deal.  Pretty sure this code comes on with abs and tcl lights, but why did those lights come on?  Tell you what, I've almost had it with this car now, it's really testing my limits.

 

Any help much appreciated

 

By the way, at no point has the check engine light been on and the 01314 was related to the ABS block

To be honest my car did some very strange things when it brake light switch was duff. Odd running, limp mode, boost surging etc..

I only noticed something was up when i braked using cruise control and the engine floored itself to keep at my selected speed even though i was braking. I at first thought the CC was broken but over the next week after i noticed i had to press the brake pedal at least 3cm before the lights lit up. That then got me thinking that i had always had to press the pedal a fair bit before the lights lit up. I swapped the switch which cost £12 from the main dealer and all my troubles went in the bin with the old switch.

To be honest my car did some very strange things when it brake light switch was duff. Odd running, limp mode, boost surging etc..

I only noticed something was up when i braked using cruise control and the engine floored itself to keep at my selected speed even though i was braking. I at first thought the CC was broken but over the next week after i noticed i had to press the brake pedal at least 3cm before the lights lit up. That then got me thinking that i had always had to press the pedal a fair bit before the lights lit up. I swapped the switch which cost £12 from the main dealer and all my troubles went in the bin with the old switch.

Cheers for that. There doesn't seem to be an issue with the lights themselves but I may as well try it for cheapness. I'm not really prepared to start chasing a problem round the car though, got limited time and money and there is a list of other things need doing to.

What about this 17743 code? Bit of a weird one could this be linked as well? And the 01314? Seems to be one of those codes that's just thrown when something goes wrong, such as tcl coming on for no reason?

What intake are you running? Standard box or a cai

Standard box, panel filter, 80mm cold feed.

Just tried a new brake pedal switch, not that. Tcl came on, followed by hesitancy and flashing abs. No fault code other than 01314. Sitting with ignition on, abs light flashing and tcl comes on and off, as lights go on and off there is an audible click. Very confused now. Even though maf made no difference to running I'm sure the lights weren't doing this with the original, will try put it back on.

It gets stranger. Put original maf back in, I'd tried an old spare to see if I could rule out maf. Anyway, as I pulled away, 1 big hesitancy splutter and the ran fine. No tcl or abs light, car pulled smooth. Left ticking over for a while, still no lights. Turn engine off and tcl and abs at it again.

Check for codes, 01314, cleared it, checked again, says 'no code, no dtcs, or a communication error.' At times vcds has also said 'too many communication lines open' or something like that...

Tried one more ignition cycle, lights went out. Stayed off when turned engine off.

First question I suppose is this, how long would it take the ecu to learn a new switch or a change of maf?

I'm not in the habit of sitting with my ignition on so I wouldn't really know if it's normal for those lights to go off and come back on, is it normal?