Strange cut out at 5200 rpm

[adam g]

Does anyone have ideas on what could cause a consistent engine cut at circa 5200 rpm. It isn't boost/load related as it happens whether I set the boost to 13 or 26 psi.

I am running 034efi on an Aby but can't find anything in the sensing system or software, the issue started ever since I had an overboost issue while trying a stronger Wg spring and blew the plastic end cap off the intercooler. I've now fit a brand new IC and it flies up to circa 5.2k rpm but then just cuts out suddenly.

[UrS4boy]

You need to talk to 034 Motorsports.

[adam g]

You need to talk to 034 Motorsports.

Indeed, I've posted on their forum for help with the Ecu side of things.

I was really after any ideas from this forum on the mechanical side that could cause such a phenomenon (plugs, coils, etc) but I've wracked my brain and come up with nothing.

[adam g]

Just discovered it also happens when I rev it in neutral.

[GazzaG60]

no boost leaks? have you tested it.

you may have damaged a hose or somthing if the end tank parted

[UrS4boy]

Just discovered it also happens when I rev it in neutral.

I have to guess that there is a setting in the 034EFI software that you are using that has a fuel (or ignition cut) at 5200 RPM instead of say 7200 like stock.

[andyg plym]

Does the Rev counter momentarily go to 0rpm ?

[GazzaG60]

missed the neutral thing.

so it ran fine before the blow of the cooler on the same software?

[Quattro Dan.]

Chips issue.

I have had this recently with a set of chips I tried, swapped to another set or the oe and all was fine. Its a problem with the chips. I found out the hard way after swapping most of the hardware.

[andyg plym]

Yeah I was going to go down that route of suggesting chips as I had exactly the same thing and it took a long time to diagnose

[adam g]

Thank you all for your suggestions, I got it sorted today.

It turned out to be a faulty VR sensor that counts the teeth on my crank wheel. I had ruled it out as the logs showed it was reading the required 59 teeth without wavering. Someone suggested i try changing the air gap anyway. Seeing as this sensor sits right next to the intercooler and would have got a good whack when it exploded it didnt seem a bad idea.

By changing the air gap I could only make the cut out occur earlier (3000 rpm) while still counting 59 teeth strangely, but when I tried a new sensor the problem was resolved.

I thought it worth posting the solution as quite a few aftermarket systems use the 60-2 wheel and VR sensor.

The new custom intercooler has dropped the inlet temps by 20-30 degrees - had a massive smile on my face while enjoying the full rev range today.

[DJones]

Thank you all for your suggestions, I got it sorted today.

It turned out to be a faulty VR sensor that counts the teeth on my crank wheel. I had ruled it out as the logs showed it was reading the required 59 teeth without wavering. Someone suggested i try changing the air gap anyway. Seeing as this sensor sits right next to the intercooler and would have got a good whack when it exploded it didnt seem a bad idea.

By changing the air gap I could only make the cut out occur earlier (3000 rpm) while still counting 59 teeth strangely, but when I tried a new sensor the problem was resolved.

I thought it worth posting the solution as quite a few aftermarket systems use the 60-2 wheel and VR sensor.

The new custom intercooler has dropped the inlet temps by 20-30 degrees - had a massive smile on my face while enjoying the full rev range today.

Nice one.... took mine out this evening to clear its throat....