Morning Folks, I think I had a spark plug go duff on the way into work this morning, system backfired, bent my AFM, felt a bit of a fluff last night, should have changed the plugs then but hey ho, I am where I am!
I'll be swapping the plugs at lunchtime and the flap still moves when I turn it manually so I can set it to where I want it, as a get me home this evening are the any suggestions as to where is best to set the flap or should I just disconnect the plug? Its a 325 with a single point LPG system, I can "E-start" the engine on gas, the car seems to run ok at present when its up to speed but pulling away from stationary really bogs the engine down at present.
Regards
Iain
LPG backfired, bent the AFM - get me home suggestions needed
Moderator: martauto
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C33
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Brianmoooore
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Air meter doesn't do anything when running on gas, except provide a bit of ignition timing change (which isn't matched to LPG's requirements anyway), so wedge the flap wide open.
Some LPG systems use a 'flap opener' device, that keeps the flap wide open all the time when running on gas to prevent any possibility of damage if a backfire occurs.
What sort of backfire protection is on your system, and any idea why it didn't work?
When I installed the LPG system on the red touring in my sig., over ten years ago, I was supplied with the wrong size backfire protection 'cat flap', and rather than embark on the two thousand mile journey I had planned, on petrol, I drilled two 1mm holes in the air meter, top and bottom, opened the flap by hand, and slipped a piece of stiff wire through, holding the flap wide open.
Some LPG systems use a 'flap opener' device, that keeps the flap wide open all the time when running on gas to prevent any possibility of damage if a backfire occurs.
What sort of backfire protection is on your system, and any idea why it didn't work?
When I installed the LPG system on the red touring in my sig., over ten years ago, I was supplied with the wrong size backfire protection 'cat flap', and rather than embark on the two thousand mile journey I had planned, on petrol, I drilled two 1mm holes in the air meter, top and bottom, opened the flap by hand, and slipped a piece of stiff wire through, holding the flap wide open.
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C33
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OK thanks Brian.
When you say thru the air meter, do you mean thru the housing - vertically? I'll possibly do that with this knackered one and keep the replacement in the boot just in case I'm caught short with LPG.
Regards
Iain
When you say thru the air meter, do you mean thru the housing - vertically? I'll possibly do that with this knackered one and keep the replacement in the boot just in case I'm caught short with LPG.
Regards
Iain
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Brianmoooore
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Through the housing, vertically, so that the 'pin' you drop through holds the flap wide open.
If I had run out of LPG, All I would need to do is pull the pin out to release the flap.
If I had run out of LPG, All I would need to do is pull the pin out to release the flap.
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C33
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Cheers.
Regards
Iain.
Regards
Iain.
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C33
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Well day 3 of wide open AFM running and the only two things I've noticed are the engine doesn't run as nicely on the BPR7ES plugs I've put in (the spare set I had in the boot for emergency purposes) compared to the 6's it was running however it at least doesn't fluff and backfire now so it's an improvement; also the exhaust is noticeably louder running with all the ignition advance that the car is currently running something I'm not too keen on - obviously the opposite of the trick we use to get race cars under the noise tests.
The idea of stopping in the middle of the M56 to remove a pin then continuing doesnt really take my fancy, so I'm wondering if I can go the other way and use a pin to make the flap stay open, at around or just above the point where the flap sits during idle. The theory being that it will barely affect the running but in the event of another unarrested backfire the flap wont close fully allowing the pressuried gas to escape to the air box. I've looked at the dead unit at it has actually got a bump stop already fitted so I'm thinking of fabricating something in its place and hold the flap ajar?
Regards
Iain
The idea of stopping in the middle of the M56 to remove a pin then continuing doesnt really take my fancy, so I'm wondering if I can go the other way and use a pin to make the flap stay open, at around or just above the point where the flap sits during idle. The theory being that it will barely affect the running but in the event of another unarrested backfire the flap wont close fully allowing the pressuried gas to escape to the air box. I've looked at the dead unit at it has actually got a bump stop already fitted so I'm thinking of fabricating something in its place and hold the flap ajar?
Regards
Iain