backfiring...

Post by **j_robi** » 10 Dec 2006, 23:04

1.9dg with gassure lpg conv.
lpg system been spot on for over a year, best thing iv had done to the van

i use the van as daily transport for everything

twice recently i have driven for 5 mins, stopped for 20 mins then the van has refused to start, with a really loud gunshot sound coming from the exhaust
(this led to a very embarassing predicament in cardiff high street last week!)

after repeated attempts to start it, and continued backfires...after several goes the van fires up and all is good again

just wondering if anyone has then answer to the problem. just get the feeling that il get stranded at some point, with it backfiring and not proceeding to start

any ideas/explanations/courses of action appreciated, thanks JR

Post by **T'Onion** » 11 Dec 2006, 00:30

when did you last service the van ?

Post by **HarryMann** » 11 Dec 2006, 01:33

Anyone looked it over recently?

Airleaks in inlet tract or dizzie vac advance pipe leaking or blocked or its connection blocked.

Post by **j_robi** » 11 Dec 2006, 11:55

thanks for replies
it gets serviced by family, brother and father are mechanics

is it something to worry about?

Post by **HarryMann** » 11 Dec 2006, 13:28

Of course, if you've got a family of mechanics get them to look over the points mentioned so far.

Post by **speleobod** » 11 Dec 2006, 17:17

Electrical probs maybe?. Try fitting cooler plugs and gapping to half a mil. good stuff in the WIKI

Post by **T'Onion** » 11 Dec 2006, 19:28

j_robi wrote:thanks for replies
it gets serviced by family, brother and father are mechanics

is it something to worry about?

but you still haven't said when it was serviced .. could be due for some new plugs or the air filter could be old and tired

Post by **Trundler** » 11 Dec 2006, 21:15

I had some problems with exhaust backfires recently. They were caused by me fiddling to try to get a more reliable tickover and in doing so I'd turned the air bleed screw on the gas regulator out too far. It should only be open about one turn, any more and it seems to let too much air in (?)

Post by **HarryMann** » 11 Dec 2006, 21:33

but you still haven't said when it was serviced ..

Blimey T'Onion, you want answers to questions asked of someone asking for help and assistance on here...

unheard of!

Post by **toomanytoys** » 11 Dec 2006, 22:35

Backfires are usually caused by too lean a mixture... or unburnt fuel in the exhaust..
Air leaks on the exhaust can cause them too..
But I would make sure the ignition system is in tip top nick as LPG needs a good system.. time it up for 7.5 deg BTDC too, this helps it run better.

Check the inlet manifolda and pipework and connections.. for air leaks..
Then check the co, could be lean..

Post by **Trundler** » 13 Dec 2006, 20:31

Got mine running beautifully now

Backfires completely absent!

Turned the air bleed screw fully home then screwed the big black mixture screw out until engine would idle again. Turned it back in slowly until engine stalled, then opened air bleed screw one turn.

Runs like a dream now. Smooth, reliable tickover, good power and no hesitation at any point in the rev range or throttle range. The acid test will be MPG!

Post by **Rooster** » 19 Dec 2006, 12:59

I fitted a new fuel pump last week to my 2.1 gli Caravelle. Drove about 6 miles parked up, went to the bank, back to the van, then had difficulty starting it. She eventualy started but would not run, then stalled and on trying to re-start gave myself the fright on my life when it backfired like a gun going off, Got out, checked the engine and found that the pipe from the are filter to the engine had been blown off. on the engine side of the gas jet. Re-connected it all, tried to re-start it then bang it did it again. Called the RAC, RAC man took the distributor cap of removed the condensation put it back and van started on the button and has been fine since. It was a very wet day the van had been standing for days untill I fitted the pump. Sometimes the solution is oh so simple!

P.S for vans with electric fuel pumps check the thread re Fuel pump for a 2.1 gli caravelle in the technical forum.

Club 80-90 Forums

backfiring...

backfiring...

Just had the same thig.