Thread: Power Loss under Acceleration

Originally Posted by justinc

Baz, If that miss at low speeds and trailing throttle sounds like 1 or more cylinders not firing, (or a 13B bridge ported Mazda rotory engine at idle), and goes away as soon as you touch the throttle, then it isn't unusual for a flash tune ECU model, only with manual ones though. The overboost issue is as you have discovered, every flash program I do I have to thoroughly test as most require the wastegate backed off to some degree.

The fitment of a bigger IC can help this

JC

I have the whole box and dice Justin, bigger IC, 3" exhaust, silicon hoses, EGR bypass

But yes I was thinking it could be the flash tune

Originally Posted by fatman

I had the same problem,it was driving me nuts.
I lengthend the wastegate arm to drop the boost - although it didn't seem to overboost,but the boost on nanocom screen didn't drop.
I sprayed plenty of wd40 on the wastegate shaft,moved it with a pair of pliers and voila - a different disco!!
It seems that if the wastegates is hard to move,when the ecm tells the wastegate modulator to move the wastegate and doesn't "see" a relevant boost change,it cuts the fuel slightly,but doesn't store a overboost fault,you see the boost doesn't go over the "limit".
PS
It took me almost 2 months to find it

I have lubed the wastegate arm, it could be that I need to take it off and clean it up properly and lube it again, I did notice when backing the wastegate off that the numbers weren't dropping on the Nanocom, so I kept backing the arm off until they did, I have since increased the it 1/2 a turn and it now seems to be at around 230 to to 233 as the highest so the boost is about spot on now.

I will have the system checked for any leaks too, as Dave has mentioned.

Thanks everyone for your help.

Baz.

It all seems to be going well, MAF was fine, putting out the numbers it should, gave it a clean just to be sure, so far so good.

Baz.