backfiring?
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backfiring?
i have a 72 240, when im on the highway or at high speeds, when i let go of the gas a lil, it goes BANG! twice or even 4 times all at once, is that backfiring or is it something else? i went to an exclusive z shop but they want to charge me 90/hr which they say it could take them to 2 hours to 8 hours just check it! so i was wondering if anyone had any pointeers on what a backfiring sounds like? im not sure. HELP!
your carbs are running rich. a backfire through the exhaust occurs when unburnt fuel is ignited in the exhaust because of your exhaust manifold's high temperature. This also means that your car is running weaker than it should be.
you can spend $50 for a colortune to tune your carbs, and $14.95 for a haynes "how to tune and rebuild your weber and SU carbs."
Which shop did you go to? Dando's or Scott Performance? I assume Dando's, it'd explain the 2 to 8hour quote.
you can spend $50 for a colortune to tune your carbs, and $14.95 for a haynes "how to tune and rebuild your weber and SU carbs."
Which shop did you go to? Dando's or Scott Performance? I assume Dando's, it'd explain the 2 to 8hour quote.
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hey, my Z also backfires, but not as bad since I installed my electronic igniton kit. I took the car to the shop and had a mechanic work on the carburetors, and he tuned them up, but said that my linkage needed to be cleaned, and that my carburetors run a little weak up top...what all should I do? I also noticed that when the Z is fully warm and running, it backfires less and less. What could cause the backfire in the first place?
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hey, same here, the car is cold or not fully warm its a mess, it farts loud! but when i gets warm to normal temp it goes down and it only does it on the highway when im going fast. i thought it would be the webers but im not a mechanic, it does have headers and a loud exhaust system which i do not like, a muffler shop told that if i put a resonator right by the muffler the noise wil go down as well as the loud bang. you think its better to get new weber kit? or just rebuild it? the people who told me 90/hr was scott performance, theyre right down the street from my business. so i went one day and this guy he went all out on me. so i dont want to screwed for hours hours when its only something so minor.
Originally posted by ralphy
a muffler shop told that if i put a resonator right by the muffler the noise wil go down as well as the loud bang.
a muffler shop told that if i put a resonator right by the muffler the noise wil go down as well as the loud bang.
The problem will still be there. Guess what backfire does? That's right, burns up your exhaust
The problem could be the anti-back fire or "gulp valve". It's that funny looking, gold colored, vacuum type can thingy that is between your front carb and the valve cover with two large and two small vacuum lines going to it. I never new what the hell it was until I saw one for sale on eBay this week. Go to parts and acsessories 240z and search for "gulp valve". Not at all certain about any of this but since it seems to be tied into the smog system I would like to be sure before I take all that crap off. Let us know if you find out any more!
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well the only thing is that i have a 240 but it has a l28 in it, and well the gulp valve i dont see anywhere, im going to have to with the carb tune see what happens, hopefully it will stop. i was thining it was the headers, but since the carb explanation was done it makes sense, since the webers they do look pretty old and dirty. so i'll keep u guys posted. thx. i'll post some pics later so you can check out my car see how you rate it.
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