Engine won't rev to rev limiter at certain times - why????

Back again with yet another problem I'm hoping someone might have an answer for.

The car is a Mk2 golf running an ABF with jenvey DTH throttle bodies on a DTA E48 ECU. The crank sensor is an external 36-1 wheel instead of the OE internal one but other than that the engine is standard.

Basically the car will work perfectly on the road and also worked perfectly on the dyno when it was mapped 2 - 3 weeks ago (The tuner was informed of the issue beforehand but there were no problems when mapping). I thought this was going to be fixed by replacing the TPS as per my previous thread http://clubgti.com/showthread.php?2...e-with-hesitation-jolting-at-certian-tps-revs

The problem seems to occur on trackdays where I am at full throttle / going to high revs all the time and for long periods of time. At the start of a session it seems to work correctly but after a while it will only rev to 6500ish instead of 7500.

So far I have tried: HT leads (only had 1 spare with me at the time so changed 1 at a time but made no difference), Sparkplugs, & Coil.

The AFR meter stays at high 12's when it does this so it does not seem to be a fuel problem.

Think I'm going to check the crank sensor wiring next, Any other ideas?

Thanks.

 

Plugs?

Off topic slightly

Do you have a pic of your external trigger please

Edit;

Ingnore plugs I've just re-read your post

 

Here's a link to my set up in one of Nige's threads
http://clubgti.com/showthread.php?2...tails-on-ABF&p=2430522&highlight=#post2430522

 

Thanks

I don't suppose you made two spacers did you? Lol

 

I'm afraid not, only planned to do the one conversion.

 

Worth an ask lol

 

So you have a VR pickup sensor on an after market trigger wheel?

Have you tried using the OEM trigger if still fitted, with the crank sensor for a 12v VR6 or pre 1999 1.8T?

Also depending on the mounting for you aftermarket trigger wheel or sensor, you could be losing the air gap consistency which is contributing to your problem.

 

Using eddies idea you could then sell me your trigger wheel setup lol

 

Ha ha.

Unfortunately the OEM trigger wheel has been removed as I did think about that. Yes I'm using a VR sensor from a ford, do you know the recommended gap for this, its currently set as 0.7mm.

Thanks.

 

I'm sure 0.7 is correct

 

As above however sparrow can confirm what he expects his systems to be.