Hi

I'm tuning a TurboXS UTEC on my MY03 JDM STI (2.0L). I live in New Zealand and it seems no one here has done it before, so the local tuner I'm using is in the dark on the UTEC.

We were starting tuning yesterday, and found ignition timing and fuel adjustment all works OK. Came to boost control and ran into huge problems.

It seems boost control doesn't work. We were operating in closed loop mode, and starting with a value of 200 over the entire map (for > 60% TPS), max boost still was the same as under ECU control, and the boost curve maintained it's stock shape, maxing out at 4000rpm and then tapering off. We would have thought that entering a value of 200 over the entire rev range would have held boost constant at a certain value, and then we would work up from there.

We've installed the ABC correctly and the factory boost solenoid appears to be working. Any ideas as to why this is happening?

Thanks
Justin

200 is low for closed loop mode, did you increase it at all?

Yes - we tried up to 300, had no effect on boost in terms of holding boost constant.

But it seemed to have an effect on turbo spooling - with boost control on, turbo spooled at lot slower, meaning overall power curve looked MUCH worse.

Do you have CLB enabled in the constants menu?

ABC 2 turns out correct? T'd off the line to the FBC?

Yep, all good.

Might check that new downpipe splitter is not obstructing the wastegate

If you're in CLB, why are you only setting boost above 60% tps. Try starting around 30%. I think you're problem may be that you're not allowing for boost to build up.

You may also want to check you're boost gain. I think the default is 50, but you can set it for 45-47 and get a slightly quicker spool. However you could cause it to spike if it spools too quick.

Originally posted by cdvma
200 is low for closed loop mode, did you increase it at all?

my 16 PSI map has numbers in the under 200 range

Looks like boost control is working

Tried lower values (100) and boost maxes out to about 14.5 psi. It does however taper off still, so by increasing the target value to 150 over 5000 rpm, managed to stop it tapering until 6500rpm.

Is this tapering normal for a fixed target value? - I would have thought the UTEC would say "I need a target value of 100 (let's assume this is 14psi). At 5500rpm, the factory solenoid is reducing boost, to to meet the target value of 14psi, I'll increase the factory solenoid duty cycle until the MAP sensor reads 14psi".

For what it is worth . . . I had a similar problem that ended up being a restrictor with too large an inner diameter in the wastegate feedback hose.

Swapped the restrictor and all was good.