ECU

[Trevor450]

Just a quick question, does the Lucas ECU learn parameters such as the ECU in more modern vehicles?

The reason being is that I have had my Chimaera for just over a year with no real issues. I had a misfire a couple of weeks ago which turned out to be a cracked plug extender. The plugs were done in January when it was serviced and I decided to change all the extenders, HT leads, coil, distributor cap and rotor arm while I was at it as the ignition components looked fairly original to my 12 year old 60k mile car.

The idle was also hanging a bit high so I cleaned the stepper which sorted it out. What I did notice was that a slight shunting appeared when the throttle is only open a small amount (at low speed and while cruising at a constant speed) and while not the end of the world and can be driven around, is a minor irritation. What is strange is that the last couple of times I have used the car over this weekend, it has got a lot better.

I have done some digging and ordered the ACT smooth bore induction pipes but should I have reset the ECU in some way after changing all the old ignition components?

Car is a 2000 450.

[finestjammy]

Someone with more expertise will be along shorty...but I do believe it 'learns' certain parameters. It does this only when at idle. The advice I was given when you've swapped a few things over is to reset the ecu (disconnect the main cord) and let it idle for a good twenty minutes to 're-learn'. Note that the ecu doesn't adjust the timing in any way.

Happy to be flamed if I've got this wrong

[blitzracing]

You need 2.5 mins at a steady idle on a hot engine (90'c plus) for the ECU to "learn" the long term fuel trim. Otherwise it will do it bit by bit when you drive and idle over time.

[Trevor450]

Thanks guys.