Help needed

[marT350T]

Just had my 20v t motor rebuilt with new oversized pistons,rods, valves gas flowed head etc.

It was running fine when it went away and now it is back all it will do is tick over. It just cuts out over 2K.

The engine builder say that it is because that my emerald ecu hasnt got a air flow sensor ???????

Surely that amount of engine work isnt going to make my car undriveable is it ?

[Dr G]

Emerald kit runs off a throttle potentiomemter rather than a MAF unless I've got my wires crossed?

I think my first port of call would be whoever mapped it in case it is indeed an electrical problem.

Not something silly like knackered diverter valve is it?

[philip walker]

You need to read the map file.
You also should look in the live data when you are reading the emerald map file.
You may also need to re-show the values of the throttle switch to the ecu.

Edited by philip walker on Thursday 21st February 12:43

[marT350T]

Dr G said:

Emerald kit runs off a throttle potentiomemter rather than a MAF unless I've got my wires crossed?

I think my first port of call would be whoever mapped it in case it is indeed an electrical problem.

Not something silly like knackered diverter valve is it?

Yeah its going to get a new bigger turbo and injectors fitted and remapped next week.

The diverter valve was ok in November when the car went in for the upgrade. Is there a quick way to test the diverter valve ?

[Mikey-S]

If it hasn't got a Air mass meter then it will have a potentiometer and MAP sensor. I doubt it would be the diverter valve because it would still rev up, just not produce any boost. Sounds like the potentiometer is either not connected or incorrectly fitted / calibrated. Live data via a laptop is definately the way to go.

[marT350T]

Mikey-S said:

If it hasn't got a Air mass meter then it will have a potentiometer and MAP sensor. I doubt it would be the diverter valve because it would still rev up, just not produce any boost. Sounds like the potentiometer is either not connected or incorrectly fitted / calibrated. Live data via a laptop is definately the way to go.

Where is this pot located ?

[Mikey-S]

It will be on the throttle body, usually at the opposite side of the throttle cable. I'm pretty sure the garage who rebuilt the motor would have checked this when the engine didn't run right...