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Discussion Starter #1
I have discussed this at length on another forum so i was after some fresh input. Here's the problem:

When putting my foot on the clutch, the engine revs drop to near stalling . When slowing down and/or stopping at junctions etc. the car stalls unless I blip the throttle. The problem exists regardless of whether the car is hot or cold (maybe marginally worse after 30 mins or so).

I have replace the stepper motor, temp sender, lambda, spark plugs and tested the MAF by unplugging it (problem still exists).

Taken it to a "Specialist" and they said that it might be the phase sensor. Seems like a bit of guess work to me though, and I don't want to change it unless I can be a bit more certain.

Anybody got any ideas or had a phase sensor go before?
 

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Have you got an injector warning light on?
Does it happen every time you drive or is it only some of the time?

Try plugging out the phase sensor connector to see if it runs ok.
Doing this will probably put on a red light and put the ecu into safe 'limp home' mode.
Car might not start with it plugged out, although mine does. My phase sensor is literally broken in half and yes it dies out occasionaly when I stop at lights etc.
Phase sensor is used when starting the car to identify which cylinder to inject into. If your phase sensor is dodgy then when you start the car (if it starts) then it will be lumpy and willl take a few seconds to sort itself out before idling.
This sensor is also used during normal driving for both ignition and injection timings as the phase is changed by the variator.
Symptoms on mine are poor acceleration between 2k and 4.5k rpm and occasional dying out, oh yeah and a big red warning light on the dash.
 

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Discussion Starter #3
I don't have any warning lights on and it starts with no problems. Also idles with no problems. Looks like I might be able to get a sensor for a 10th of the cost of a dealer, so will have a play with it when I change my belts etc...gulp.
 

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My guess would be the air flow metre...
 

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I just thought of something! Do you have the old stepper motor? If you do try this:

Install old stepper. Leave it unplugged and plug in the new stepper. Start engine and rev it, as it comes down to idle you should see the new stepper mechanism move if it’s working properly. Or at least you’ll know if the ECU is sending out the signal to the stepper. That would rule out the ECU.

Warrior
 

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It's not the air flow meter as the problem still exists if the car is run with it unplugged.
This is not a foolproof method.
It does work a lot of the time... but not always.
:rolleyes:
But it doesn't seem like a typical air flow meter problem.
:confused:
 

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Discussion Starter #8
Hmm, an interesting idea Warrior. I will have to have a play with that. The best test for that would be on a rolling road though.
 
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