1.4 irratic rev counter.. Help please!!

[andy m]

Hello,

Have just had the car serviced by the main stealer. 1.4 polo 8v 1997.

Car came back an had mysteriously gained a misfire. Checked the car in the dark and could see the leads flashing. Have changed the leads, cap and rotor. Mis fire seems to have gone apart from small intermittent misfire at idle.

However, the rev counter now seems to blip up and down randomly at idle. It does not coincide with any misfire or change in note from the engine. It has also done it at higher revs under load, agin with no change in engine noise or notable misfire.

Is this the ECU relearing after the change or leads etc?? What is going on? I would have thought that the rev counter would only "blip" with a change of engine tone or increase in revs. It seems very random.

Help, please!!

Thanks,

Andy.

[andy m]

The plot thickens
.
Had the car hooked up to a VAG system thingy today. Throttle body fine, temp senser fine etc, but no signal from Lamda probe.

Would this account for the problem? Does it mean the Lamda is knackered? Does it need a clean? or is it just that there is a problem in the wiring. Loose connection?

Any ideas would be appreciated.
Thanks.

[R1CH]

no idea fella,,,,i personally would have said throttle body as mine did the same and thats what it was. Lambda probe wouldnt cause that though.

[shauni boi]

hi mate did you get the problem sorted? i have the same problem on my polo at the moment no sigional from the lampda sensor!

[bstardchild]

hi mate did you get the problem sorted? i have the same problem on my polo at the moment no sigional from the lampda sensor!

So replace it

The Lambda

They don't last forever - 75-85K is normal life expectancy

On some modern larger cars they are a service item (by service I mean changed every major service)

[bstardchild]

PS nice to see someone use the search facility even if it was a bit of a thread resurection!!!