Stalling in 4th and 5th

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jon_d_h
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Tue Feb 17, 2009 9:51 pm

Got a small problem. When on the move, I put my clutch in in 4th or 5th for along time, the engine will stall and cut out. What could be the problem? I have recently been having problem with the idling being to low with original chip but not with the "wild" chip. The TPS is clicking in the correct place so should be ok, the IVC has been replaced so should be ok. I cant see or hear any air leaks but there maybe one some where. What do you think?
Which hoses should I replace to may sure?

Also, what could faulty HT leaks cause and how can I tell if one is faulty?

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sati
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Tue Feb 17, 2009 11:30 pm

it might just be a clog injector or fuel filter try running sum Fuel Injector Cleaner to see if that helps and replace the the fuel filter. an air leak wont cause an engine to cut out or stall , maybe the ecu need's to be reset to refresh it self check the wikki for a guide.
jon_d_h
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Wed Feb 18, 2009 9:07 am

Hi

Forgot to mention, Its on LPG so wont shouldnt have anything to do with the fuel system. I have reset the ecu when following the chip fitting guide so dont think its that. Couldnt having a very small air leak cause this?


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town325i
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Wed Feb 18, 2009 9:14 am

it could be an a worn dizzy cap and rotor arm some e30's are still using there orgional ones because of how much they cost new from the dealer for dizzy cap and rotor are its £110
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Brianmoooore
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Wed Feb 18, 2009 9:29 am

If this is a single point venturi LPG system (Leonardo?), then I doubt if there's much wrong with the ignition system. Ignition faults tend to make themselves known on LPG cars in quite a dramatic manner!
Does this happen on LPG and petrol?
IS it a Leonardo system?
If so, what does the laptop display show?
Why do you want to press in the clutch for long periods when driving along?
jon_d_h
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Wed Feb 18, 2009 9:30 am

Ok

How can I tell if it is warn? I dont want to replace it if its not warn out.

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jon_d_h
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Thu Feb 19, 2009 12:44 pm

Brianmoooore wrote:If this is a single point venturi LPG system (Leonardo?), then I doubt if there's much wrong with the ignition system. Ignition faults tend to make themselves known on LPG cars in quite a dramatic manner!
Does this happen on LPG and petrol?
IS it a Leonardo system?
If so, what does the laptop display show?
Why do you want to press in the clutch for long periods when driving along?
It is a single point verturi leonardo system. Just tried it out and the problem is only on LPG. I have not looked at the laptop yet but what should I be looking at and for?
Well, I way just testing the idle and noticed it stalling only in the top gears.
What you think?

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Brianmoooore
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Thu Feb 19, 2009 8:12 pm

I still can't work out why you want the engine to idle when in 4th and 5th gears, but assuming the problem is while you are moving at speed, the problem is possibly the effects of air being forced into the engine by the forward motion of the car.
Try it with the pipe from the panel behind the LH headlamp to the air filter box removed.
Ilkorin
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Thu Feb 19, 2009 9:35 pm

This is interesting, I have the same problem when I take the car out of gear when coming to a stop (roundabouts etc.) from a decent speed (4th or 5th?)...I just assumed that it was one of the downsides of running LPG that it won't return to idle quite as well as it would on petrol. Just fitted a catflap in the intake, so maybe that will make a difference...
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Brianmoooore
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Thu Feb 19, 2009 10:45 pm

Stalling under braking can also be caused by the vapouriser being mounted with its diaphram at right angles to the car. The diaphram is affected by the 'g' force, and leans off the mixture.
Ilkorin
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Thu Mar 05, 2009 7:16 pm

Finally got the engine to idle on LPG today, the idle speed is so low, and dropping it from anywhere over 1500 back to idle will stall it.

Does the ECU look at engine speed or lambda at idle - i.e. am I just looking at pushing up the idle in the software (which will be an issue because I don't have it....or an interface for a laptop for that matter) or would I need to figure out what's causing a lean spike at return to idle and work from there?

similar to OP, Leonardo single point system
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Brianmoooore
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Thu Mar 05, 2009 9:08 pm

Engine ECU controls the idle speed - nothing directly to do with the gas system, but it will struggle if the fuel mixture isn't correct.
You can't set the system up properly without seeing what's happening on a laptop, or set the required software options.
Software for the Leonardo, I can supply, as well as a couple of circuits for an interface.
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