so what would make one of these engines backfire under hard accel

[dieselpilot1969]

mine started that today, got to say it came as an unwelcome suprise!

 

[Prairie Dog]

A leaking fuel injector will make them backfire under compression but I'm not sure what could cause it under power.

 

[DF5152]

when did it back fire and what did it sound like?

 

[ROADWARRIOR]

Does it blow smoke when it does it? I was tinkering around with a cold air intake of my own and had it backfire and blow blue smoke when I got above 30psi one day. Ended up finding the airfilter was sucking my heat insulation around the filter under high boost.



Dan

 

[Greg Boardman-RIP]

Our engines wont backfire. They cant. It is a missfire. I have had it happen twice. It is caused by low fuel pressure. Check your fuel filter. Mine did it after I installed DDIII's. Changed fuel filter and now its fine..... Greg

 

[mmi]

I had this happen last year @1500 miles.

Thought it could not happen also.

Sure felt like gas eng. with too much unburnt fuel in exhaust.

Happened @ short (50')onramp to freeway. have to merge in after full stop( great design plan)

Thought it may be ( turbo bark after reading posts)

It is flat leaving industrial park,truck moderatly loaded,6spd shifted smooth for once.

Did 3 times 3-4-5th gear Too involved with traffic to watch boost

any thoughts??

Currently equiped as stock ,but would like to add jacobs with enough input (APPS,TPS, exhaust size issues) no self back pressure as yet

 

[dieselpilot1969]

Ok got it figured out, bad fuel. As it happens I for the last year with exceptions for being out of town have always once per week filled up at the conoco fillin station off I-30 in garland tx and last 3 fillups it has been doin this backfire thing. Well went to fill up this past saturday and could get no fuel due to what they said was a computer malfunction and not one pump was working, so I went back to rockwall and filled it at exxon, well problem solved. As to what it sounded like; when I floored it from a dead stop 1st gear was fine when it hit second it would start popping out the tailpipe at around 2000 rpm's untill I let off the pedal. As to what could be wrong with the fuel, well

 

[Vaughn MacKenzie]

Last summer when the spark plug was starting to go bad on my diesel-powered lawnmower, man it did it ever pop a good one. kaPOW!!! A diesel backfire isn't a pop, it's a violent BANG! 'Bout blew the muffler right off the ol' Briggs & Stratton. You can't tell this boy diesels don't backfire



Vaughn

 

[DPKetchum]

Have a CLOSE friend with a 03 2500 h. o. auto and he commented several months ago that his fell on its face on accel on to a interstate and sounded like it backfired threw the intake. Did it twice in a couple of weeks and not again in 10 thousand miles or so.

 

[DF5152]

Originally posted by dieselpilot1969

Ok got it figured out, bad fuel. As it happens I for the last year with exceptions for being out of town have always once per week filled up at the conoco fillin station off I-30 in garland tx and last 3 fillups it has been doin this backfire thing. Well went to fill up this past saturday and could get no fuel due to what they said was a computer malfunction and not one pump was working, so I went back to rockwall and filled it at exxon, well problem solved. As to what it sounded like; when I floored it from a dead stop 1st gear was fine when it hit second it would start popping out the tailpipe at around 2000 rpm's untill I let off the pedal. As to what could be wrong with the fuel, well

. ok well if thats what u have narrowed the problem to i would change the fuel filter immediately

 

[Crunch]

Originally posted by Vaughn MacKenzie

Last summer when the spark plug was starting to go bad on my diesel-powered lawnmower, man it did it ever pop a good one. kaPOW!!! A diesel backfire isn't a pop, it's a violent BANG! 'Bout blew the muffler right off the ol' Briggs & Stratton. You can't tell this boy diesels don't backfire

I'm more concerned that you believe there is a spark plug on your diesel lawn mower. Is this true, or is it more along the lines of the saleman who came upon a country farm where the husband was running around the yard clucking like a chicken? The salesman asked the family if they had ever considered taking the man to a shrink. They said they had, but that they also really needed the eggs.

 

[Vaughn MacKenzie]

Originally posted by Crunch

I'm more concerned that you believe there is a spark plug on your diesel lawn mower.

Heh. . . there *is* a spark plug in my diesel lawnmower Crunch :-laf



You can read about my spark-ignition diesel foibles here: The Ol' Briggs & Stratton Diesel Vaughn

 

[Crunch]

Originally posted by Vaughn MacKenzie

Heh. . . there *is* a spark plug in my diesel lawnmower Crunch :-laf



You can read about my spark-ignition diesel foibles here: The Ol' Briggs & Stratton Diesel Vaughn

Great thread! And what a nice freak-out to see some HVAC posts come back at me.



I second the motion for a glow plug. I bet you could go to a hobby store and find a glow plug for a model airplane that would fit.

 

[DF5152]

just buy and oil firing spark plug 1 or 2 heat ranges hotter so it keeps it cleaner

 

[Pawpaw]

Originally posted by dieselpilot1969

Ok got it figured out, bad fuel. As it happens I for the last year with exceptions for being out of town have always once per week filled up at the conoco fillin station off I-30 in garland tx and last 3 fillups it has been doin this backfire thing. Well went to fill up this past saturday and could get no fuel due to what they said was a computer malfunction and not one pump was working, so I went back to rockwall and filled it at exxon, well problem solved. As to what it sounded like; when I floored it from a dead stop 1st gear was fine when it hit second it would start popping out the tailpipe at around 2000 rpm's untill I let off the pedal. As to what could be wrong with the fuel, well

I've been buying fuel at the Love's truck stop on I-30 in Rockwall. Seems to be the best price around ($1. 48 last night), plus they do a lot of business with the big rigs. I wouldn't expect to get a bad load of fuel there.



Bob