plentywahalla
|
| posted on 21/2/10 at 05:46 PM |
|
|
Help ... I've got musical gremlins in the TinTop
The missus car (MGZS 1.8 KSeries) has got a bug.
Leave her on tickover and the engine revs to 3000, then back to 2 then back to 1... wait a few seconds then up to 3 and so on.
Up and down the scale like a mechanical Mary Poppins! Quite spooky standing outside the car watching it.
I get a puff of white smoke when it hits the 'high c' and a small backfire which suggests that its metering too much fuel.
Any suggestions? apart from entering it into Eurovision?
|
|
|
|
|
omega 24 v6
|
| posted on 21/2/10 at 05:48 PM |
|
|
Air idle valve??
If it looks wrong it probably is wrong.
|
|
|
plentywahalla
|
| posted on 21/2/10 at 06:33 PM |
|
|
I was thinking maybe the TPS sensor giving a false signal to the ecu to deliver more fuel.
The overrich mixture condenses in the inlet manifold, backfires causing the MAF sensor to shut the fuel delivery down. then it starts again.
The odd thing is the rythmic cycling. Its got to be some kind of circular process.
|
|
|
britishtrident
|
| posted on 21/2/10 at 06:53 PM |
|
|
Check the inlet manifold is tight and sealing against the head, clean the idle control valve with carb cleaner and re-synch the valve by putting the
key in the ignition and with the drivers door open turn the ignition on but don't start the engine then depress the throttle pedal fully and
let it back up slowly 10 times.
If that dosen't work read the fault codes.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
britishtrident
|
| posted on 21/2/10 at 07:02 PM |
|
|
quote:
Originally posted by plentywahalla
I was thinking maybe the TPS sensor giving a false signal to the ecu to deliver more fuel.
The overrich mixture condenses in the inlet manifold, backfires causing the MAF sensor to shut the fuel delivery down. then it starts again.
The odd thing is the rythmic cycling. Its got to be some kind of circular process.
MEMS dosen't have a MAF sensor nice reliable system fuel mapping is soley on MAP, TPS, CTS and crank sensor.
All the other sensors have little or no effect on mixture.
Idle speed as other inputs AC Trinary switch, power steering pressure switch.
Idle speed is controlled by a cobination the Idle speed control valve and ignition timing. Adjustment of idle speed is carried out by he idle control
valve bit minor fluctuations in idle speed are stabilised by retarding and and advancing the ignition between about 8 btdc and 14 btdc
[Edited on 21/2/10 by britishtrident]
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
