timing belt ?

can a stretched timing belt with 140,000 miles on it cause a car to backfire
or pop at the tailpipe,even though the timing marks line up? also can this
cause the timing on a scan tool to jump around? is there a sure way of
telling if i have a bad computer,timing belt or distributor? thanks

 

Posting year, make and model would help!!

Glenn Beasley
Chrysler Tech

 

hello Glenn, still my 98 dodge stratus 2.5 v6 not fixed to date. Randy

 

and compression your gonna need a scan tool to verify sensor inputs and out
puts. I believe this vehicle went from a hard start to a no start if I
remember correctly so the next step is scan tool diagnostics

 

you are correct. i went out and started the car after it's been sitting and
it started right off. it just doesn't sound right. it almost sounds like the
cat is clogged. the garage i had it at said they did a flow test on it and
it was fine? the only thing he found with his scan tool was the timing
seemed to be jumping around a bit when he drove it. he said all sensors
tested out fine? he couldn't find the problem. I'll find another place to
take it to. the motor is too noisy in the front end like not good flow and
it makes the lifter noise more pronounced. still searching for answers. :-(

 

The distributors on those vehicles would fail internally and cause the car
to run like shit. If I remember correctly the car would start fine cold but as
the engine warmed up it would run worse and worse until it qiut and possibly
not restart. It would cause the car to run similar to a plugged cat but I
think the timing was just way retarded because it had no power at all. What I
found to work for diagnosing the problem was to take a big screwdriver/prybar
and put it at the base of the distributor were it meets the engine block. Next
, take a hammer and give it a good hit on the end of the pry bar.If the
distributor was the problem the car would cut off when you hit the pry bar. A
replacement distributor fixed the problem. I ran across 8 or 10 with bad
distributors and my test method worked on every one of them. Its easy enough
to try it.

 

thanks Mike, this is the 3rd remanufactured distributor that was put into
this car. i read somewhere never to use them and only use oem ones. i'm
starting to believe this now. your method might be hard to do on this car
because the distributor is a little hard to get at , but I'll try it. how
does this work though?

 

Yes, the distributor is hard to reach on the 2.5 V6. I used a long
prybar/screwdriver that is about 2-3 feet long. I took one of the distributors
apart to see what failed but i don't remeber exactly what it was, being this
was close to 20 years ago. If I remeber correctly there was a small circuit
board for the distributor pick up that failed. The vibration from tapping with
the hammer caused the problem to appear. You have to give it a pretty good hit
with the hammer but don't hit it hard enough to break it. Once I found this
method of testing worked I used it on 8-10 cars and it never failed to find a
bad distibutor. If the distributor is good it will have no affect at all no
matter how hard you hit it.

 

You mean no matter how hard you hit it as long as you don't hit it hard
enough
to break it? ;-)

It is very common for hall-effect sensors to fail intermittently due to
heat. The
crank and cam sensors on many Chryslers will do the same thing. The
distributor
remanufacturers very likely do not replace the electronics, only the
bearings
and such. I would try getting a circuit board from a wrecker first, though.

Ted

 

You mean no matter how hard you hit it as long as you don't hit it hard
enough
to break it? ;-)

It is very common for hall-effect sensors to fail intermittently due to
heat. The
crank and cam sensors on many Chryslers will do the same thing. The
distributor
remanufacturers very likely do not replace the electronics, only the
bearings
and such. I would try getting a circuit board from a wrecker first, though.

Ted

 

well mike thanks for the reply. it sure is worth a try. i had this
distributor out and ohmed the coil primary and secondary and they both
seemed fine. maybe it's failing under load.