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  #1  
Old 25th September 2006
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Default Stuttering as it comes on boost...

I have a T16 which starts to stutter as it gets to about 3k rpm. The stuttering seems to be linked to the boost pressure rising as the turbo starts to spool.

The car has a dodgy distributor hall sensor cable. The connector has snapped off the side of the dissy and is hanging loose out the side of the dissy. I'm guessing this is the problem as the car has refused to start because of the broken connector so it can't be in good order. I reckon as the pressure starts to build in the manifold the vac capsual is moving the dissy and causing the connector to break its connection.

I also found the ignition module was hanging loose. Does the ignition module need to ground to the body-work? Could the fact that it was losely hanging by 1 screw have caused the stuttering? I have a feeling it's not that because it seems to start when the boost builds up - still thinking it must be the dissy.

There was also a vac-hose missing between the cruise control pump and the y-peice which connects it to the rest of the vac-system. Likewise I don't think that would be causing the problem either - still think it's the dissy.

I will replace the dissy but does anyone have any other ideas?
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  #2  
Old 25th September 2006
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from my experience (which may be lacking) the vacuum canisters action should only move the innards of the distributor - not the whole thing - it should be moving the plate that - if this were a points ignition - the points would be mounted to - but a broken hal sensor connector can't be a good thing! As for "periodic contact ground" on the ECU - that I'd try to resolve as soon as possible -
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  #3  
Old 25th September 2006
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Quote:
Originally Posted by ejenner
I also found the ignition module was hanging loose. Does the ignition module need to ground to the body-work? Could the fact that it was losely hanging by 1 screw have caused the stuttering? I have a feeling it's not that because it seems to start when the boost builds up - still thinking it must be the dissy.
The ignition module need not be grounded to the body work for the engine to run. However it should be secured tightly, as the body acts as a huge heat sink for the ignition module. I'd suggest to fix it asap to avoid killing the ignition module.
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Old 25th September 2006
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yes it's just the inside part of the distributor which moves. but the wires for the sensor are attached to the mechanisim and when the thing moves it must be pulling the wires.
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Old 25th September 2006
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I have the same issue, my dizzy is a bit dodgy as well but recently "fixed" it... hmmm
__________________
Turbo allows the valiant who has appeared at the wheel SAAB to gain momentum for 200 km/h Charm SAAB Turbo also that it to you not bad Porsche on it it is possible with speed of pregnant turtle feeling itself in full comfort which by the way our hero obeys a rudder reliably and confidently the truth management hardly will twirl a steering wheel by one finger uneasy. Without the hydraulic booster quickly enough perishes a steering shaft, but to change its hemorrhoids from the most fierce
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  #6  
Old 26th September 2006
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I recently had a similar experience on an auto gearbox, when the oil level was a little low. It felt as if the engine was stuttering, but in fact the auto gearbox was slipping.
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Old 26th September 2006
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I'm sure this is an ignition cut / fuel cut sort of problem but as the dissy is already broken I'm pretty sure the dissy is causing the problem.
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Old 28th September 2006
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yes it was the dissy causing the problem. Replaced it today and no more stuttering.
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