Hi all,

Just had the car serviced, it was running like a dream except the engine backfires/farts every now and again.

It's suggested because I use ULP, I should use additives like "ValveMaster"(I was told the name) if I use ULP, are they like fuel booster?

Any tips or suggestions will be appreciated.

Thanks,
Ron

[Edited on 25-3-2004 by ronster]

Firstly, valvemaster, Flashlube and the like are nor octane boosters, just a cushioning aget for the valves to help prevent valve and seat recession when older cars without hardened valve seats are run on unleaded fuel.

next, is the backfiring on throttle off or throttle on.

If its on throttle off (overrun) then it will be that the tuner has set the slow run setting on the carby/s nice and lean and should be considered nothing to worry about.

If the popping/farting is during throttle on, then I suggest you take the car back to the "tuner" and suggest he tunes it properly this time!
L8tr
E

Just went for a drive and paid more attention to it...

The backfiring/poping/farting happens when my foot is off the accelerator...

tassupervee: I'm hoping it's like you said, it's nothing to worry about.

Will keep monitoring :thumb

I'd suggest that the exhaust may be loose. Did the mechanic remove the exhaust? and if he did..did he use new exhaust gaskets. Dubs backfire off throtel when there is an leak in the exhaust system or occasionally if the pee shooters are in to far missing (from my own testing...kinda fun to shoot 2m flames) or as tassupervee mentioned it could be the carb. Make sure that the idle adjuster on the carb is just making contact with its stop when you are off the gas.

7 outta 10 times when I shift from 3rd or 4th to 2nd off the throttle, it will let out a pop...

Does it narrow down the problem?
Can anyone help?

sounds like a hole in the exhaust, or as previously mentioned by someone, a loose exhaust.....

kai

could be a f#!?ed valve seat. that caused alot of trouble with popping in my kombi.

Is it "gunshot backfire" or a "pop and gurgle" sound? my car pops and gurgles on lift off, but thats just the way its set up, (big carbies and open exhaust) while if its a gunshot, I would assume its a leak in the exhaust system.

Hi BiX,

It's more like a 'Poping' sound not gurgling.

Ron

Hi all,

Just an update on this problem I USED TO have.

Thanks to everyone who helped out, it turned out as most of you suggested - there was a leak in the exhaust.

Thanks to the guys from VVDS, who repaired my heater boxes - where it had the leak!

Boris from VVDS used a stethoscope(the hearing thing that doctors and nurses carry around) like thing, without the metal bit at the end to listen for leaks around the muffler then the heater boxes and found out the leak was coming from where the heater boxes connect to the muffler! It was amazing for a novice like me to see him work! :P

Boris showed me a neat trick (I think most of you would know this already :P), if your exhaust system does not have a leak, you can use your hands to block off the tail pipes and the engine should stop in a few seconds! I will definitely try this next time I hear a popping or farting sound to check if there's a leak in the exhaust system. Just make sure the pipes are not burning hot tho!

Ron
:bounce