Warm low Rev Misfire fixed by resetting ECU.

[cccscotland]

Not really needing advice, but thought I'd post this for future misfire sufferers to find as any references to doing this are buried deep in other threads.

I had a misfire that occurred only when the car was warm and under load. I checked out a few of the things here, with none making a difference, then today, I saw a reference to an ECU reset. Remembering that the last time I'd driven the car without misfire it was throwing all sorts of error codes due to a blown clock fuse, I thought I'd give it a go:

http://daliracing.com/v666-5/info/article_read.cfm?articleID=888

Easy, free and worth doing before throwing loads of dosh at the car replacing stuff. My car doesn't have anything funky done to it, it is pretty much stock. And whilst the revs didn't rise and fall as the process said it would, driving it for an hour without issue after shows the process seemed to cure it.

Car is a UK 95, with 2 pin coils. I think that makes it the same as a 94 US car.

 

[cccscotland]

Just to add, after consulting with NSX Guru Kaz, this can also happen if you have a flat battery and need a jump, or use a battery isolator switch, (which I did).

 

[Larry Bastanza]

Did you retrieve the codes? Do you know what they are? all misfire?

 

[cccscotland]

Did you retrieve the codes? Do you know what they are? all misfire?

2-pin coils so no error codes. Just what felt like a really bad misfire at low revs. I'm guessing that I inadvertently taught the ECU a bad fuelling map by blipping the throttle to warm up after reconnecting the battery? The car was sitting for a year with the battery disconnected before that.

Anyway, as I said, I saw no advice that people complaining about a misfire should do this - it is a free, easy thing to try before spending $$$ on new parts.