Hi guys. I've just taken my car out after around a year off the road while I was fixing some oil leaks etc (engine out).

Car Spec:

Built 1.8, 1050cc injectors
MS3Pro PNP
LS Coils
GTX2860R Gen 2, Kraken top mount, 3 inch exhaust
BMW box, Cadillac CTS Getrag Box

Now, on the same tune, the car seems to be doing two things. Under load, it seems to reach around 5000rpm and go bananas, popping noises from exhaust and cutting all power. It's not launch control or flat shift. And I can't figure it out. I've attached a datalog of the issue (120, 127 and 243 seconds in). I notice the AFR goes incredibly lean just before hand, but seems impossible looking at the fueling table. Can anyone chime in?



The second issue is when driving very moderately under light throttle applications the engine will simply cut out. I need to re-engage a gear and drop the clutch to get the engine to fire back into life. This could be as low as 3000rpm and hardly any throttle input (10% or so).

 

Somethings cutting fuel, boost duty is also going to 100%. Your alternator isn't working during that log either, max of 12.6, min of 11.7 volts.

Can you attach the tune as well?

 

Thanks for taking the time to look at that Curly. I've attached the tune to this post.

 

It's loosing sync as far as I can tell. There's a few other issues, such as the batt v I mention earlier, it's a bit lean early in the pull, and your sig says 400hp, but you're only making 200kpa. I see the EBC dial is only ~50%, but you're 24% boost duty, and only max out at 28% if you turn the dial to max? Not very important to your issue, just observation.

As for the sync, look into crank sensor, cam sensor, sensor gap? Did you do a front main seal and knock it back a bit? I've found when running a 36-2 wheel, the OE spec is too big, causes issues like you've described/logged.

 

thanks Curly. I’ll check the gap at the trigger wheel. It says 400hp yes and normally would be if I was using the actual boost duty table. I reduced the table to try and find out the fault (thought it was maybe hitting over boost protection but it’s not).

boost duty.. its been so long since I looked at this car. Seems weird. I'll fix it so the first table is 0 (WG pressure) and the second is max boost I want to run (can see this is now fixed in the next post)

once I fix this issue I’ll put the boost duty table back to normal.

alternator… I’m still using the mk1 unit (the car is VVT swapped). I’ll check the wiring and see if I can get to the bottom of that.

 

It's working!

It seemed to be the gap on the crank angle sensor was too large. Order has been restored in the world. Thank you!

Btw ignore the AFR in the pic. I was targeting low 11's but it always goes half a point richer when the methanol injection is running (which it was).

 

You can buy a 100+ amp alternator that fits like stock for very little money on ebay. I bought one and it held up fine. It was 120 or 130 amps or something.

 

Thanks for the heads up on the alternator.

From reading another thread, I suspect the alternator is behaving a little weird is because I deleted the standard instrument cluster in favour of an AIM MXS unit.

I'll probably look at wiring in an NB alternator and using the MS to control it.

 

I would vastly prefer an internally regulated alternator for reliability.