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I better start at the start, incase any of the information is useful

I Bought myself a '92 R32 GTS-t last wednesday, with 155500km on it (appear genuine). It had a Turbosmart V-port BOV, a Really Dirty K&N Pod Filter, some form of 3" Catback exhaust.

Wednesday night, i took it for a drive on the highway, and i noticed that above 4000rpm it was 'missing', i.e. a cylinder wouldn't fire, but other than that, the car seemed to run fine.

I took it for a service today, and put new Motul 4100 Turbolight oil, new Oil Filter, and NGK BCPR6ES plugs. While they were off, we tested all the coilpacks and they all tested at around '1' resistance.

The plugs that were in there were a mix and match of all sorts, completely wrong heat range etc etc.

Anyway, after i left the service, i noticed there was now a miss at idle, only slightly, and only very occasionally, it just wouldn't fire a single cylinder.

Went out to willowbank for the day (spectating at the sprints) and on the way out, it still had the miss above 4000rpm.

On leaving, i gave it a bit of a squirt on the highway and the miss above 4000rpm was 'semi' gone... like, it feels nowhere near as bad as it used to, but it still doesn't feel 'right'... and general running seems a tiny bit rougher than it used to be. Idle also has a slight miss in it still.

I guess the question is, what are your opinions as to what could be causing the problems?

Oh, and i also am resetting my ECU tonight to see if it is something that it has learnt along the way.

Any ideas/help would be great... thanks

Jason

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was the miss there when you test drove it before you bought it?

I didn't notice it when i test-drove it, but then again, i didn't really rev it over 4000rpm when i test-drove it either.

I reset the ECU last night, and this morning its still missing slightly at idle, but the miss above 4000rpm seems ALMOST completely gone

As you've checked the coils i'd reset the ecu and then go for a drive and then check the error codes as it's free and easy. Then start swapping things, possibly coils, ignitor, afm crank angle sensor.

As a how to: disconnect battery, turn on ignition and hold down brake pedal for about a minute to make sure there is no chage left in the system. Reconnect the battery. This will have removed any fault codes from the ecu memory so if you check now it will read 55 (all clear)

Take the car for a drive around the block (10minutes or so just to make sure everything is up to temp)

access the ecu in the passenger foot well and on the bottom of it there is a little knob with a flat head screwdriver slot in it. turn on the ignition but dont start the car. Turn the knob fully clockwise (i think) and leave it there for 5 secs or so, then turn it back full the other way. You are now in diagnostic mode. Slow flashes of the led next to the knob are 10s (10,20,30..) and fast flashes are 1s. It also flashes the exhaust temp warning light on the dash.

error codes here (Thanks Skyline_boy)

http://www.skylinesaustralia.com/forums/sh...ead.php?t=35733

hopefully this can give some direction in what to look at. I am currently experiencing something similar but have not yet solved it but have swapped pretty much every major component with a signal to the ecu that varies significantly with revs and gotten to the point now where i'm looking at the ignition loom.

Let us know how you go as it all adds to the knowledge base of the forum.

Good luck

Dave

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