Problem – ‘lil Help Pls - Major Torque Loss Below 4000rpm, Running Rough, Idle Hunting – Any Ideas?

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Last Friday night, cruising at about 100Km, pretty neutral boost (approx 2000rpm in 5th) and died in the arse. Motor still starts with a lot of difficult on cold starts, runs rough and idle hunts, no excessive smoke/backfiring. When it went it felt just like it would when an intercooler hose pops off. But they are all fine.

Best way to describe it is like a giant torque hole before about 4000rpm, you can put your foot flat & drive through it, then makes power from 4000rpm onwards. About 20mins before it happened it felt like it was missing a bit around 4000rpm when under a slight load.

Diagnostic steps taken thus far on the RB26:

All hoses were fine – 1 very small vacuum hose was off at the rear of the motor

Replaced AFM’s – no probs

Replaced CAS (with 3 different ones) – no prob

Plugs – fine

Compression – fine

TPS - fine

FC – input sensor volts fine. But timing was out between what the FC thought it was reading/sending & what the timing was actually at the engine. Was more retarded then what the FC thought, FC couldn’t advance the timing.

Thought it was the FC, swapped FC with Wolf 3D, seemed to work a little better, but still couldn’t get a satisfactory tune in the Wolf for down low.

Reset FC to base tune, after trying to dial in a conservative safe tune it seems to go into ‘limp home mode’ ditching the parameters & puts the engine light on.

The AWD light is now coming on too, usually this indicates that the ATTESA has shut down the AWD.

Next thing to check maybe inlet manifold gasket.(?)

Any ideas?

[double overhead sun visors]

Opps sorry for double post lol..

delete this one pls...

[Faid]

dude it can be a range of problems, id be cheking the trubs, maybe one let go, or it could be your coils, your plugs, as i said a range of problems. have it diagnosed at a professional workshop.

[MBS206]

Tim's car, as far as I know, has been in at a professional workshop.

[TurboX]

What does the ECU error code functions say?

I am having probs not quite the same though and get error 34 - knock sensors (Just replaced!)

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As Matt said it’s at a professional workshop.

Don’t think it would be a turbo, no pop/bang when it went, it was also on fairly neutral boost, & it still makes heaps of power above 4000rpm.

No diagnostic error’s on the FC, but it wasn’t setting the correct timing…

Now engine warning light comes on since resetting the FC.

Any other ideas?

[SLIPPERY]

try stock ecu again and see what happens

[double overhead sun visors]

Got the wolf 3D to work, no stock ECU anymore, just swapped the stock ECU for an oil cooler...