Rough start, and rough idle when warm

[thenixtone]

Hey guys,

 

Sometimes when I start my R34 GTT (98, NEO) it sounds like its stuttering or spluttering, but it starts each time. Then when it gets warm and I'm sitting at lights or just idling, the revs will go up and down and low enough sometimes to almost stall (but it hasn't yet). I have no idea what this could be, I purchased a new Z32 AFM and installed it, but the car ran like shit as I'm guessing it needs to be tuned for the new one (so I put the old one back in).

 

Help is appreciated  

[GTSBoy]

Yes, well, you can't run a Z32 AFM against a standard ECU without Nistune, correct.

I would suggest that your IACV would be dirty/sticky/blocked, hence the engine's inability to control revs. But all the roughness could be just about anything. AFM (dying, dirty, broken solder joints), CAS (same), injectors (dirty, broken loom plugs/pins), coils (same).  The list goes on.

[thebe]

Test your pipework for boost leaks.

[thenixtone]

Yeah it has a z32 currently but it's apparently not OEM and a replica. I think it could be that, but I need a retune for the new AFM and no one within 800kms will tune a nistune 

[thenixtone]

When I got the car looked at by a mechanic (it had a check engine light) they said the light was from the throttle actuator or o2 sensor. I'm guessing this is related, but what does that mean / what would be the fix? Sheesh

 

The car also idles at 1100 rpm

Edited May 7, 2019 by thenixtone

[KiwiRS4T]

You can install it yourself with a little effort:

http://www.kudosmotorsports.com/catalog/lambda-oxygen-sensor-suit-nissan-skyline-25gt-25gt-25gt-rb25de-rb25det-p-187.html

[thenixtone]

8 hours ago, KiwiRS4T said:

You can install it yourself with a little effort:

http://www.kudosmotorsports.com/catalog/lambda-oxygen-sensor-suit-nissan-skyline-25gt-25gt-25gt-rb25de-rb25det-p-187.html

Link is dead, and the official Nissan mechanic wasn't sure either, he also said 'a retune will probably fix the issue' but I don't think that's true

Edited May 8, 2019 by thenixtone

[thebe]

The link works fine. It leads to rb o2 sensor on the kudos website

 

Also change the AFM for genuine one.

 

 

[thenixtone]

Yeah link works now, was 400ing before.

I switched the AFM out but it ran like butthole, needs a retune someone said, but no one tuned nistunes anywhere near me, so big F