Mazda Rotary Club

General => General Technical => Topic started by: dturpin on July 21, 2006, 11:08:22 PM

Title: Very Rough Idle
Post by: dturpin on July 21, 2006, 11:08:22 PM
I have jut rebuilt my 92 FD and converted to single turbo (secon hand).  I have had the secodary\'s ported with a new FPR and fuel rail with 1600cc injectors, I have also removed the air con pump and the air pump.  I have changed the relevent settings on the Apexi FC, for the injectors and single turbo, although the injector size is only set to 1500cc (max of the Apexi).
The car is struggling to idle, it almost stalls then picks the revs back up and they drop again instantly, it is also smoking a bit, is this normal for a rebuilt engine?
If not can anyone offer any advice on how to solve the issues.
Title: Very Rough Idle
Post by: Gman on July 22, 2006, 09:52:21 AM
Mine did this (not on a fresh rebuild) 2 problems - 2 plug leads were wrong way round and the idle control valve was fubar\'d.
Title: Very Rough Idle
Post by: Gman on July 22, 2006, 09:52:54 AM
Have you got any error codes on the apexi.
Title: Very Rough Idle
Post by: dturpin on July 22, 2006, 12:16:46 PM
No there are no fault codes up on the Apexi.  Im pretty sure the leads are on the riht way, will double check though.  How do I know if the idle control valve is knackered is there a way of testing it?
Title: Very Rough Idle
Post by: kbareham on July 22, 2006, 06:25:08 PM
I would try adding a little more fuel around the idle area in the map. My guess is that the engine changes you made need a bit more fuel to keep it happy.

From memory, there is a global trim on the controller. You could try increasing this with a warm engine to see whether it helps. This setting is not maintained, so you will need to remember how much you added, and then add this to the fuel correction map around the idle cells. The map tracer will show you which cell(s) it is idling at. Sorry, can\'t remember exactly where the settings are - I have no commander any more.
Title: Very Rough Idle
Post by: Carl on July 24, 2006, 11:54:34 AM
Lean the engine out a little at idle.
Give me a buzz if you like.
Regards
Carl