ECU reset after Stepper Motor Change.

[reddersv8]

Replaced Stepper Motor recently, and looking through old Posts on here, I've seen it stated you should 'reset the ECU' following this. What would this involve please anyone? I know where it lives as I've changed Fuses in the past that are hidden behind this and the Battery. What exactly should I disconnect and when??
Cheers. Paul.

[K4TRV]

If you can get to it, disconnect the ECU cable/socket for 30/60 secs, its next to the battery depending on year. Or, disconnect the battery earth, again min 30 secs, if you are happy that you can re-set the alarm etc??

Trev

[blitzracing]

The stepper should reset automatically on ignition power off on a cold engine. You should hear a buzz from the stepper as the ignition goes off, showing the stepper has reached its end stop position. Recently however Steve Heath has idenitfied that some of the TVR ECU chips dont have this bit working correctly, leading to some idle problems. An ECU reset will have no bearing on the stepper position.

[sheel]

Changed mine yesterday didn't know anything about a reset runs lovely now (year 2000) must have been lucky!!

[reddersv8]

OK, thank you both. Yes I have heard the buzz from the Stepper as it re-sets, so I was a bit baffled as to why the ECU should be re-set. I replaced the ECU coolant temp sensor which I'm told is a common problem within the ECU system. I also changed the vacuum pipe that runs off the Plenum adjacent to the Stepper as it was split, thus losing vacuum pressure!

One further question please; the vacuum pipe that runs from the distributor to plenum I plan to replace as its splitting in places. What does this do [ignition retard?], and would affect running if split??

Cheers, Paul.

[blitzracing]

It retards the ignition when you are under light throttle. This makes for better fuel consumption, but it wont effect the overall power however at higher throttle openings.

[Simon says]

blitzracing said:

It advances the ignition timing when you are under light throttle. This makes for better fuel consumption, but it wont effect the overall power however at higher throttle openings.

ETA I know you knew what you meant Mark

[blitzracing]

Thanks for spotting the deliberate mistake- just testing to see if you were awake.....