I've recently noticed that my exhaust pops when I'm coasting. e.g when i'm pulling up slowly to traffic lights or a junction. I don't have it de-catted. Do you think it is blowing or backfiring. I've had the car for over a year and that's me just noticed it. Cheers.

 

Does it happen only after a long run? ie when the exhaust is hot?

If so and it didn't do it before, then your car may be running richer than usual - has fuel consumption got worse recently?

If so then a sensor may be failing, maybe MAF or Lambda sensor.

 

The ECU could be running FUEL OVERUN setting and is not harmfull.
WRC rally cars use this setting and im sure others on here have similar seting.

Mine works best when i take it for a nice and slow easy run and then after about 10 mins i rev it up to get that famous pop.

 

Have you got a uprated d/v on mate?

 

No it's an unmodified P1. I changed the MAF recently as I was getting some erratic idle and slight hesitation. That cured that problem.

 

Have you reset the ECU? If it's still fuelling from what it learnt from the old MAF, it'll be overfuelling, which could account for the pops...

 

I didn't reset when I changed MAF. Is it easy to do? I heard it has something to do with connecting wires under steering column but not 100% sure on the procedure. Help much appreciated. Cheers, Graham.

 

I used to cheat & just leave the battery disconnected overnight
I did try the ECU reset once, but got thoroughly confused (& spent more time swearing at the various cables than anything else!) so found the disconnect easier