Re: Engine backfire
 

OP said "injected chevy" I think you could bet the farm that it's a
stock 350".
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Mike Romain wrote:
>
> What engine and what Jeep?
>
> Some GM engines have quirks....
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's

Re: Engine backfire
 

OP said "injected chevy" I think you could bet the farm that it's a
stock 350".
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Mike Romain wrote:
>
> What engine and what Jeep?
>
> Some GM engines have quirks....
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's

Re: Engine backfire
 

Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
(in other words, sounds like I'm in for a pricey repair.)

What is the downside to leaving it unrepaired? (Emissions are not a
concern as I have antqiue tags and am therefore inspection exempt.)

Also... it is virtually always sounds like it is the right exhaust
pipe, not the left. Does this indicate that my air leak is probably
in that half of the system?

L.W.(ßill) ------ III <----------@cox.net> wrote in message news:<4032CD9E.F2394E1@cox.net>...
> As Paul said you have oxygen in the exhaust, common on SMOG engines
> with an air pump, but an injected engine shouldn't have one to pass
> SMOG. Do you have one anyway carried over from an old AMC engine? Or you
> have an exhaust header leak that needs to be fixed.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> "ezeppelin@msn.com" wrote:
> >
> > What are the most common causes and remedies for engine backfire?
> >
> > (At least, I think backfire is the correct term for my problem... it
> > is an occasional loud 'bang' as if from gunfire, which seems to
> > emanate from near the catalytic converters under my floorboard rather
> > than up in the engine compartment.)
> >
> > Anyway, assuming that I am using the correct term... I have a jeep
> > with a fuel injected chevy engine, and it backfires from time to
> > time. Every occurence is when the engine is revving down (e.g., I put
> > the clutch in.) However, beyond that, there is no rhyme or reason...
> > sometimes it will happen 3 times in an hour, other times it might go
> > weeks with no backfire. I can't detect any other common factor
> > besides revving down (e.g., it happens regardless of whether the
> > engine is hot or cold, what gas I'm running, etc.)

Re: Engine backfire
 

Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
(in other words, sounds like I'm in for a pricey repair.)

What is the downside to leaving it unrepaired? (Emissions are not a
concern as I have antqiue tags and am therefore inspection exempt.)

Also... it is virtually always sounds like it is the right exhaust
pipe, not the left. Does this indicate that my air leak is probably
in that half of the system?

L.W.(ßill) ------ III <----------@cox.net> wrote in message news:<4032CD9E.F2394E1@cox.net>...
> As Paul said you have oxygen in the exhaust, common on SMOG engines
> with an air pump, but an injected engine shouldn't have one to pass
> SMOG. Do you have one anyway carried over from an old AMC engine? Or you
> have an exhaust header leak that needs to be fixed.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> "ezeppelin@msn.com" wrote:
> >
> > What are the most common causes and remedies for engine backfire?
> >
> > (At least, I think backfire is the correct term for my problem... it
> > is an occasional loud 'bang' as if from gunfire, which seems to
> > emanate from near the catalytic converters under my floorboard rather
> > than up in the engine compartment.)
> >
> > Anyway, assuming that I am using the correct term... I have a jeep
> > with a fuel injected chevy engine, and it backfires from time to
> > time. Every occurence is when the engine is revving down (e.g., I put
> > the clutch in.) However, beyond that, there is no rhyme or reason...
> > sometimes it will happen 3 times in an hour, other times it might go
> > weeks with no backfire. I can't detect any other common factor
> > besides revving down (e.g., it happens regardless of whether the
> > engine is hot or cold, what gas I'm running, etc.)

Re: Engine backfire
 

Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
(in other words, sounds like I'm in for a pricey repair.)

What is the downside to leaving it unrepaired? (Emissions are not a
concern as I have antqiue tags and am therefore inspection exempt.)

Also... it is virtually always sounds like it is the right exhaust
pipe, not the left. Does this indicate that my air leak is probably
in that half of the system?

L.W.(ßill) ------ III <----------@cox.net> wrote in message news:<4032CD9E.F2394E1@cox.net>...
> As Paul said you have oxygen in the exhaust, common on SMOG engines
> with an air pump, but an injected engine shouldn't have one to pass
> SMOG. Do you have one anyway carried over from an old AMC engine? Or you
> have an exhaust header leak that needs to be fixed.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> "ezeppelin@msn.com" wrote:
> >
> > What are the most common causes and remedies for engine backfire?
> >
> > (At least, I think backfire is the correct term for my problem... it
> > is an occasional loud 'bang' as if from gunfire, which seems to
> > emanate from near the catalytic converters under my floorboard rather
> > than up in the engine compartment.)
> >
> > Anyway, assuming that I am using the correct term... I have a jeep
> > with a fuel injected chevy engine, and it backfires from time to
> > time. Every occurence is when the engine is revving down (e.g., I put
> > the clutch in.) However, beyond that, there is no rhyme or reason...
> > sometimes it will happen 3 times in an hour, other times it might go
> > weeks with no backfire. I can't detect any other common factor
> > besides revving down (e.g., it happens regardless of whether the
> > engine is hot or cold, what gas I'm running, etc.)

Re: Engine backfire
 

Make yourself a stethoscope and see if you can find it cold.
Leaving it leak will foul your oxygen sensor, making your electronic
injection richer, which in turn fouls your spark plugs and washes down
your cylinder walls of lubricant, hastening wear.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

"ezeppelin@msn.com" wrote:
>
> Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
> (in other words, sounds like I'm in for a pricey repair.)
>
> What is the downside to leaving it unrepaired? (Emissions are not a
> concern as I have antqiue tags and am therefore inspection exempt.)
>
> Also... it is virtually always sounds like it is the right exhaust
> pipe, not the left. Does this indicate that my air leak is probably
> in that half of the system?

Re: Engine backfire
 

Make yourself a stethoscope and see if you can find it cold.
Leaving it leak will foul your oxygen sensor, making your electronic
injection richer, which in turn fouls your spark plugs and washes down
your cylinder walls of lubricant, hastening wear.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

"ezeppelin@msn.com" wrote:
>
> Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
> (in other words, sounds like I'm in for a pricey repair.)
>
> What is the downside to leaving it unrepaired? (Emissions are not a
> concern as I have antqiue tags and am therefore inspection exempt.)
>
> Also... it is virtually always sounds like it is the right exhaust
> pipe, not the left. Does this indicate that my air leak is probably
> in that half of the system?

Re: Engine backfire
 

Make yourself a stethoscope and see if you can find it cold.
Leaving it leak will foul your oxygen sensor, making your electronic
injection richer, which in turn fouls your spark plugs and washes down
your cylinder walls of lubricant, hastening wear.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

"ezeppelin@msn.com" wrote:
>
> Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
> (in other words, sounds like I'm in for a pricey repair.)
>
> What is the downside to leaving it unrepaired? (Emissions are not a
> concern as I have antqiue tags and am therefore inspection exempt.)
>
> Also... it is virtually always sounds like it is the right exhaust
> pipe, not the left. Does this indicate that my air leak is probably
> in that half of the system?

Re: Engine backfire
 

Just wondering - wouldn't the old test of hanging a shop cloth over
the end of the tailpipe pretty well identify a possible valve problem?
Hold it so it hangs straight over the end of the pipe. It will blow
out, maybe falling back to touch the pipe, unless you have an actual
exhaust valve problem which will try and suck it up the pipe when that
cylinder is in the right position. That will cause a backfire, BTW,
and it can be pretty hard to spot if it's a weak valve spring.

On Thu, 19 Feb 2004 02:36:46 UTC L.W.(ßill) ------ III
<----------@cox.net> wrote:

> Make yourself a stethoscope and see if you can find it cold.
> Leaving it leak will foul your oxygen sensor, making your electronic
> injection richer, which in turn fouls your spark plugs and washes down
> your cylinder walls of lubricant, hastening wear.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> "ezeppelin@msn.com" wrote:
> >
> > Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
> > (in other words, sounds like I'm in for a pricey repair.)
> >
> > What is the downside to leaving it unrepaired? (Emissions are not a
> > concern as I have antqiue tags and am therefore inspection exempt.)
> >
> > Also... it is virtually always sounds like it is the right exhaust
> > pipe, not the left. Does this indicate that my air leak is probably
> > in that half of the system?


--
Will Honea <whonea@codenet.net>

Re: Engine backfire
 

Just wondering - wouldn't the old test of hanging a shop cloth over
the end of the tailpipe pretty well identify a possible valve problem?
Hold it so it hangs straight over the end of the pipe. It will blow
out, maybe falling back to touch the pipe, unless you have an actual
exhaust valve problem which will try and suck it up the pipe when that
cylinder is in the right position. That will cause a backfire, BTW,
and it can be pretty hard to spot if it's a weak valve spring.

On Thu, 19 Feb 2004 02:36:46 UTC L.W.(ßill) ------ III
<----------@cox.net> wrote:

> Make yourself a stethoscope and see if you can find it cold.
> Leaving it leak will foul your oxygen sensor, making your electronic
> injection richer, which in turn fouls your spark plugs and washes down
> your cylinder walls of lubricant, hastening wear.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> "ezeppelin@msn.com" wrote:
> >
> > Yick. Tracing out smog and exhaust leaks are way beyond my skill set.
> > (in other words, sounds like I'm in for a pricey repair.)
> >
> > What is the downside to leaving it unrepaired? (Emissions are not a
> > concern as I have antqiue tags and am therefore inspection exempt.)
> >
> > Also... it is virtually always sounds like it is the right exhaust
> > pipe, not the left. Does this indicate that my air leak is probably
> > in that half of the system?


--
Will Honea <whonea@codenet.net>