R34 Gtr Won't Idle

[Bsa]

did you replace the vac lines could have a split in there some where. have you snapped the knock sensors not sure how they are on a 26 but i snapped one on my 20 and it wouldnt idle

[Chris-06R]

Hey Norman, got a nismo MFD...

If I got the intake smoke tested is that likely to show up any leaks that my method didn't?

Bsa - nope, didn't replace any vac lines but I couldn't find any signs that any were damaged. The car went into the garage fine - put an oil filter relocation kit on it, and now it doesn't idle... very frustrating trying to track the problem down.

[Bsa]

Did you pull the intake manifold off? Seems like it would be vacume leak just strange

[mr 32]

Hey Norman, got a nismo MFD...

If I got the intake smoke tested is that likely to show up any leaks that my method didn't?

Bsa - nope, didn't replace any vac lines but I couldn't find any signs that any were damaged. The car went into the garage fine - put an oil filter relocation kit on it, and now it doesn't idle... very frustrating trying to track the problem down.

sounds like they didnt set the nismo mfd correctly, this wouldnt be effecting your idle however just wrong % shown on the mfd.

smoke test depends on how they do it. best way is do the 'start ya bastard' test. spray some around the vac hoses if the revs go up you found the leak.

let me know if you need a hand

[Chris-06R]

Yeah, I sorted the MFD issue by rotating the TPS - now reads 0-95% or something, which is better than before...

Can anyone suggest any electrical diagnostic tests I can do which might help to point to the problem? If I got hold of a wideband oxy sensor would that enable me to determine if I have a vac leak? (i.e. car would be lean at idle?) Is there anything else I can do?

[BJM 24]

Checked for bad earth or power? cause sensors may not be receiving enough power. Had similar problem with mine ended up earth wire.

[Chris-06R]

Ok, so I think I've finally fixed it!

Connected the standard ecu and started it up to try and log any fault codes - car idled fine, maybe a little too low ~600rpm.

Didn't stall at all after about 5 mins of idling and on/off throttle so I hooked up the PFC - all good there too...

Car was still idling too low though and was struggling a bit, so I wound out the idle screw and got it back up to 800rpm - idled smoothly after that.

So what changed???

My theory now is that the remote filter and oil cooler put extra strain on the oil pump and because my idle was probably too low already it couldn't keep the engine turning... Today's warmer weather probably helped it a bit and now that I've set the idle higher it shouldn't be a problem. If this is not the reason then I have no idea, the car has magically healed itself...

[DVS JEZ]

It was probably the idle up that helped it