[MattOz]

All,

I've got a small problem with my R33. It seems to be that when cold it wil not pull away cleanly. This occurs for between 2 and 5 minutes depending on driving conditions. It then seems to disappear. However, occasionally the car feels sluggish above 5,000 rpm when warm too.

Just wondering whether the car needs an ECU reset or something similar. It's been serviced at Middlehursts, and last time they could not detect a fault! There is definitely something amiss, but I'm not sure what.

Is it sensible to reset the ECU? How do I best go about it? If this causes no change, I suppose that new plugs and leads would be advisable.

The car is using little or no oil, and head gasket seems fine as there is no contamination that I can see.

Any advice would be gratefully received.
Cheers

Matt

 

[SteveC]

Hi Matt,

I'm no expert but it sounds like a plug issue, how far along the tuning road are you and do you have std plugs ?

I remember someone else talking about a fault similar to this, but cannot recall the thread title, perhaps someone else will remember.

I think it was something to do with the way the ECU interpretted something when the engine was cold..... Dirty air flow meters ?

checking the AFM's is a quick job, just to see if they are covered in sh1t.
plugs are equally quick once you have them.....

Phil has posted how to reset the ECU if you wish to go down that route.

HTH

Steve

 

[MattOz]

Cheers Steve,

The car is totally standard. I'll have a look over the weekend, and see if there is a dodgy plug or something along those lines. Being naive, where is the AFM? I guess that'll be easy to diagnose once I've found it.

Which plugs would you guys recommend? I imagine that mine are just the standard ones.

Cheers
Matt

 

[s2gtr]

have a look at "cold pressure" on this forum posted by joss it sounds similar to your problem. not smart enough to link it for you i'm afraid.
also jez had a problem with air leaks if that helps.

 

[SteveC]

http://www.gtr.co.uk/forum/upload/showthread.php?s=&threadid=444&highlight=cold+pressure

I hope that works...

The AFM's are located behing the air filter box, on the front of the pipes, one of which has twin turbo written on it.

enjoy...
Steve

 

[Peter]

Matt,

What fuel are you using? Do you use octane booster at all?

Peter.

 

[MattOz]

Peter,

I'm using Optimax but without Octane Booster. Car is totally standard, so hoped that just Optimax would be OK!

Guess I should crack out the NF or Millers!

Steve,

Thanks for the link. I had a look, and it appears that I'm not alone, which makes me feel better!

Matt

 

[Peter]

Matt,

I had thought that perhaps you were getting some det. and the ecu had cut boost and timing as it's programmed to do prevent it. Is your car a Japanese car still with the original ecu? If so, it may be worth running her for a week or two with OB and see if there's any improvement.

Optimax is definitely better than all the other SULs I've tried. I don't get much showing on the det. reading of the PFC but it is definitely significantly less with Optimax as I no longer use OB for road use only for the track.

Peter.

 

[Shin]

You can check

Hi,

The possible causes are,

- Air Flow Meters
- O2 sensor
- Spark Plugs

You can check them and I hope you can find either one gets dirty or wrong.
About the fuel, the octan rate is almost the same situation between in the UK and in Japan.
Most of Japanese petrol is around 97.5 to 98.5 ron.
There is the standard called JIS(Japanese Industrial Standard?) and they say that premium unleaded means more than 97.5 ron.
So, conclusion, it is no problem while you are using Shell Optimax.

Yours,
Shin

 

[DCD]

Shin...does your car run OK over there? No problems at all?

 

[Shin]

No problem.

Hi, Dino.
It is no problem.

Yours,
Shin