Engine Mapping

[bobv8s]

Could someone help me. I have been told that the reason I have a poor idle is that the ECU needs re-mapping. What does this mean and how do you do it?

[350matt]

The Engine Control Unit controls the amount of time the fuel injectors are held open depending on how fast the engine is turning and how much air is entering the engine these two parameters form the X & Y axis of a table also referred to as a 'map'.
Depending on how sophisicated the injection system is tends to determine how well this base map works from car to car. On the early injection systems there are very few self diagnostics and any slight variation of the engine from the one that the 'map' was created upon leads to running problems such as your poor idle.
Check for air leaks after the airflow meter; by spraying a little lighter gas around each joint and all the hoses after the throttle body. If the engine picks up then you've found your leak.
If your car does genuinely need re-mapping then I'd suggest Mark Adams, you can reach him thru Tower View .

Matt

[GreenV8s]

quote:Could someone help me. I have been told that the reason I have a poor idle is that the ECU needs re-mapping. What does this mean and how do you do it?

If your engine is essentially standard, it's far more likely that you have a sensor fault which is throwing the ECU out. Although you probably *could* remap the ECU to compensate, it doesn't sound like the right solution to me. I've had all sorts of sensor failures and wiring faults over the last few years and hundred thousand miles or so, and Tower View have diagnosed and fixed them all. I think it's well worth getting specialist help if the problem isn't obvious, you can waste a lot of time and money trying to guess what the problem is and can easily end up making things worse.

Cheers,
Peter Humphries (and a green V8S)