Author Topic: Backfire  (Read 3196 times)

Taleb

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Backfire
« on: December 04, 2017, 09:32:59 »
Hi all ,

I fixed new 6 original injectors on my 280sl , ever since the car start backfiring during deceleration, anyone knows what could be the reasons ?


Pawel66

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Re: Backfire
« Reply #1 on: December 04, 2017, 13:08:24 »
Maybe the engine finally got some fuel through the new injectors? ;)

Too rich now?
Ignition timing to be adjusted?
Plugs/leads?

I am just guessing a bit, do not treat it as potential cause statement - let's see what the others say.
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

Raymond

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Re: Backfire
« Reply #2 on: December 04, 2017, 14:28:10 »
Is the car a manual or automatic?  There is a switch on manual transmissions that is intended to cut off the fuel flow to prevent backfires on deceleration.  Many people disconnect it because it isn't really much of a problem and if it fails it might interfere with normal fuel injection pump operation.  How bad is the backfire?  Light popping or does it sound like it will blow the muffler off?

Ray
'68 280SL 5-spd "California" Coupe

Taleb

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Re: Backfire
« Reply #3 on: December 04, 2017, 14:47:27 »
hi Rymond , its not bad backfire and the car automatic ...thanks

Taleb

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Re: Backfire
« Reply #4 on: December 04, 2017, 14:48:10 »
you are right , lets wait .

stickandrudderman

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Re: Backfire
« Reply #5 on: December 04, 2017, 17:41:37 »
Having fitted the new injectors you did then check the Co didn't you.


Pawel66

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Re: Backfire
« Reply #6 on: December 04, 2017, 19:59:18 »
 :)
Pawel

280SL 1970 automatic 180G Silver
W128 220SE
W121 190SL
G-class

GGR

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Re: Backfire
« Reply #7 on: December 05, 2017, 07:08:34 »
Backfiring on the intake side is a sign of too much ignition advance or bad valves. Usually happens on acceleration.

Exhaust popping on deceleration is usually a sign of too much ignition retard.

Did you have you ignitiion tempered with at the same time you fixed your injectors?