Uneven power delivery

[Socr8s]

Have noticed that once I get going and up to decent operating temperature that I am developing a bit of a lull in power in 2nd gear accelerating through 2000 - 3000 rpm and then power seems to kick back in again. Has the kind of feeling when driving as if there is a turbo lag (which obviously there isn't). Does this sound like it could be major engine repairs or is it something that could be sorted out more easily. Have just had 12 000 mile service and nothing identified particularly when had this done one month ago

[ChrisA]

I don't know the answer, but I too have a similar feeling under acceleration, the power seems to come in bands as you go up through the rev range.

I have read somewhere that resetting the ECU allows the ECU to re adapt itself and brings the car back to being smooth again. I also read that you need to get the engine temp up to 90 before the ECU will begin to learn.

Am I totally wrong, will this help, will it improve power delivery?

Thanks

Chris

[Nuggs]

I had a lull at around 2,500rpm when pressing on (not temp dependent though), which was cured with a new set of HT leads...

[blitzracing]

The standard lucus ecu (that TVR used)cannot be reset as such, although the later Sagem system used on the Range Rover can be. If the problem is a new one, Id first all check the HT side of things, (Things like even the plug lead positions can have an effect on the V8). A minor misfire can make the engine go flat and with so many plugs to fire everything needs to be in good nick. I doubt its anything mechanical or expensive.

[biggiles]

blitzracing said:

The standard lucus ecu (that TVR used)cannot be reset as such

I thought it could be "reset" by disconnecting the battery for a while? Not sure how long though before the memory would be lost.

[TVRThomo]

biggiles said:

blitzracing said:

The standard lucus ecu (that TVR used)cannot be reset as such

I thought it could be "reset" by disconnecting the battery for a while? Not sure how long though before the memory would be lost.

I had a cutting out problem that was driving me mad! After a lot of money spent on various things (see various other threads) the last thing i did was to disconnect the ECU, I also clean the pins on the adapter for good measure, and guess what it's never cut out since! My point ... IMO it look like disconnecting the ECU does reset it.

Oh and for what its worth i too have a litle Hesitancy between 2000 and 3000 in 2nd gear from time to time. Could be a characteristic of a V8 ??

Edited by TVRThomo on Thursday 2nd November 12:48

Edited by TVRThomo on Thursday 2nd November 12:53

[chassis 33]

I've had a few flatspot issues this season on the racer, then the car totally cut out at Oulton, so checked absolutely everything. I found that cutting out was a FUBAR ignition module, but also I found the two tin ECU relays were heavily corroded internally. As one of them feeds power to the AFM and injectors, it's a fair assumption that if the AFM isn't seeing full power it will be giving dodgy signals to the ECU.

Regards
Iain

[M@H]

TVRThomo said:

I had a cutting out problem that was driving me mad! After a lot of money spent on various things (see various other threads) the last thing i did was to disconnect the ECU, I also clean the pins on the adapter for good measure, and guess what it's never cut out since! My point ... IMO it look like disconnecting the ECU does reset it.

Reset it to what though..? its not adaptive therefore it runs the same map all the time. Surely all "resetting" the ECU will do is take it from running the standard map, to running the standard map again having removed some error codes of any previous faults.

[TVRThomo]

M@H said:

TVRThomo said:

I had a cutting out problem that was driving me mad! After a lot of money spent on various things (see various other threads) the last thing i did was to disconnect the ECU, I also clean the pins on the adapter for good measure, and guess what it's never cut out since! My point ... IMO it look like disconnecting the ECU does reset it.

Reset it to what though..? its not adaptive therefore it runs the same map all the time. Surely all "resetting" the ECU will do is take it from running the standard map, to running the standard map again having removed some error codes of any previous faults.

Hi Matt,

I think maybe you might be right it just removed some error codes, not quite sure, but the end result was no more cutting out! I'm not at all technical minded and fogive me if i'm talking rubbish but all i'm saying is that my problem seemed to be resolved when I unplugged the ECU ?

Cheers
Neil.