ECU reset

[SteveOS3]

Having noticed a dip in mpg from 33ish on a regular run to 27mpg and definite rich smell of unburnt fuel I decided to go for an ECU reset as the car had only done about 500 miles in the last year.

I've done this a few times before without problems but this time the engine splutters and dies when the throttle pot is disconnected - I had a spare and it made no difference. I also had a new ISCV so went all in and changed that too but the problem persists.

I can't find any air leaks between the AFMs and plenum, the air filter has been removed and cleaned along with the AFMs themselves.

I don't know where to go from here in terms of the reset and I've a pretty good idea that the emissions will be a problem when the next MOT comes around.

Any ideas on the reset problem would be gratefully received as I'm hoping that it will sort the rich fuel mixture issue.

Thanks,

Steve

[v8s4me]

Maybe it just needs a good thrashing?

[Spanish S2]

v8s4me said:

Maybe it just needs a good thrashing?

+1

[GreenV8S]

Has it been serviced recently? Dirty plugs or an ignition fault could cause those symptoms.

[SteveOS3]

Now that we're out of lockdown on this side of Offa's Dyke the good thrashing is coming this weekend - my main concern is why the engine dies when the throttle pot is disconnected.

It hasn't done this before and I'm wondering if this indicates a potential problem elsewhere in the system.

Steve

[v8s4me]

Have you seen this other post explaining how to check if the TPS is functioning properly?

https://www.pistonheads.com/gassing/topic.asp?h=0&...

[SteveOS3]

I have now, I'll have a look asap.

Many thanks.