timing? What else could it be?
09-02-2009, 10:15 AM
#107
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Year: 1991
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OK can you give a little more detail about it seeming to advance and retard itself
did you turn the crank and see if the distributor has any hesitation
when you move the crank back and forth
did you turn the crank and see if the distributor has any hesitation
when you move the crank back and forth
09-02-2009, 01:16 PM
#108
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Year: 1998
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Well, everyone trying to diagnose this over the internet is like a crowd watching a house burning down and not being able to stop it.
She did a good job on re making her initial post so that anyone who looks in now should have a better perspective of what has transpired. If you noticed, I was the first responder on this thread and I have read every word since the beginning. I have spent HOURS and HOURS thinking, researching and writing. There was some stuff I didn't even know til she redid that first post ... like the head and the bouncing advance. This is a smart girl and has some pretty good help so I think, at least I HOPE, we're farily close to the end.
On another note, and anyone who has contributed on this thread NOT withstanding, I have always noticed on these types of forums (I contribute to several) a tendency to 'sharpshoot' the issue. Sometimes that is helpful and it is always interesting to me, but sometimes the old plodding, careful, thoughtful ways of diagnosing are necessary. If this is NOT one of those times, well, I'll eat my hat
... soon we'll know. 
09-02-2009, 05:14 PM
#111
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LOL ... I know, huh, Dan?
She did a good job on re making her initial post so that anyone who looks in now should have a better perspective of what has transpired. If you noticed, I was the first responder on this thread and I have read every word since the beginning. I have spent HOURS and HOURS thinking, researching and writing. There was some stuff I didn't even know til she redid that first post ... like the head and the bouncing advance. This is a smart girl and has some pretty good help so I think, at least I HOPE, we're farily close to the end.
On another note, and anyone who has contributed on this thread NOT withstanding, I have always noticed on these types of forums (I contribute to several) a tendency to 'sharpshoot' the issue. Sometimes that is helpful and it is always interesting to me, but sometimes the old plodding, careful, thoughtful ways of diagnosing are necessary. If this is NOT one of those times, well, I'll eat my hat ... soon we'll know.
She did a good job on re making her initial post so that anyone who looks in now should have a better perspective of what has transpired. If you noticed, I was the first responder on this thread and I have read every word since the beginning. I have spent HOURS and HOURS thinking, researching and writing. There was some stuff I didn't even know til she redid that first post ... like the head and the bouncing advance. This is a smart girl and has some pretty good help so I think, at least I HOPE, we're farily close to the end.
On another note, and anyone who has contributed on this thread NOT withstanding, I have always noticed on these types of forums (I contribute to several) a tendency to 'sharpshoot' the issue. Sometimes that is helpful and it is always interesting to me, but sometimes the old plodding, careful, thoughtful ways of diagnosing are necessary. If this is NOT one of those times, well, I'll eat my hat
... soon we'll know. but would make me go back to thinking cps or tps.
and the fact it runs for a little bit and pops and backfires on acceleration makes me think its retarded to much
09-02-2009, 05:34 PM
#112
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Yup, Mike ... know what you're sayin' ... I've actually been thinking lately in terms of a fuel line restricton ... 'specially in light of the fact that it runs reasonably well for a short time at idle then dies and subsequently restarts ... hmmm.
Is there only one fuel filter on that year, Mike ... or is there a second one tucked somewhere that has not been found yet? I have seen stuff like this before on other vehicles. Or possibly a crimped fuel line somewhere along the line? ... Karen has been quiet today but I bet she's been working ... yup ... bet she has.
ALSO ... If they just hooked the FP up to 12v and watched it run, that can backfire on you. Those pumps work submerged and under load ... sometimes they appear to be good when tested in that manner but actually aren't. Maybe they could hook up the fuel pressure guage and watch it while the motor dies ... would be pretty interesting to see, wouldn't it?
Is there only one fuel filter on that year, Mike ... or is there a second one tucked somewhere that has not been found yet? I have seen stuff like this before on other vehicles. Or possibly a crimped fuel line somewhere along the line? ... Karen has been quiet today but I bet she's been working ... yup ... bet she has.
ALSO ... If they just hooked the FP up to 12v and watched it run, that can backfire on you. Those pumps work submerged and under load ... sometimes they appear to be good when tested in that manner but actually aren't. Maybe they could hook up the fuel pressure guage and watch it while the motor dies ... would be pretty interesting to see, wouldn't it?
09-02-2009, 05:34 PM
#113
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Ok well the other injectors were put in, and it seems to be spraying a little better like more of the mist rather than a straight stream. My bro and fiance said they look fine. The O-rings need replaced cause a couple are leaking pretty bad.
I looked up the info on how to check and adjust the TPS. The 1 that was changed didn't seem to be getting the proper reading so we switched em back and I adjusted and it is now correct...5.4v input and 4.42v output (82%).
Still not running well, still backfiring, not taking throttle, and still shutting off after a min or so. (I was actually there in person today to see for myself and give true feedback)
So that was it for today. Tomorrow we will be testing the O2 sensor. No one ever mentioned that that could be a problem. Is that because it can not be part of the problem or what? How bout the Cam? Is there a way to test/check?
I am trying so hard here. I leave for vacation in Disney Florida on Sept 10. I worked hard and saved up to take my kids. This will be my familys first time there and our first real vacation.
I am praying that this is finished before we go so I don't have the headache when I get back. Chuck (my fiance) and I have been fighting like crazy over this jeep. All I want is for him and I to work together as a team and fix it...together.
I looked up the info on how to check and adjust the TPS. The 1 that was changed didn't seem to be getting the proper reading so we switched em back and I adjusted and it is now correct...5.4v input and 4.42v output (82%).
Still not running well, still backfiring, not taking throttle, and still shutting off after a min or so. (I was actually there in person today to see for myself and give true feedback)
So that was it for today. Tomorrow we will be testing the O2 sensor. No one ever mentioned that that could be a problem. Is that because it can not be part of the problem or what? How bout the Cam? Is there a way to test/check?
I am trying so hard here. I leave for vacation in Disney Florida on Sept 10. I worked hard and saved up to take my kids. This will be my familys first time there and our first real vacation.
I am praying that this is finished before we go so I don't have the headache when I get back. Chuck (my fiance) and I have been fighting like crazy over this jeep. All I want is for him and I to work together as a team and fix it...together.
Last edited by karen7; 09-02-2009 at 05:37 PM.
09-02-2009, 05:41 PM
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09-02-2009, 05:46 PM
#116
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Yup, Mike ... know what you're sayin' ... I've actually been thinking lately in terms of a fuel line restricton ... 'specially in light of the fact that it runs reasonably well for a short time at idle then dies and subsequently restarts ... hmmm.
Is there only one fuel filter on that year, Mike ... or is there a second one tucked somewhere that has not been found yet? I have seen stuff like this before on other vehicles. Or possibly a crimped fuel line somewhere along the line? ... Karen has been quiet today but I bet she's been working ... yup ... bet she has.
ALSO ... If they just hooked the FP up to 12v and watched it run, that can backfire on you. Those pumps work submerged and under load ... sometimes they appear to be good when tested in that manner but actually aren't. Maybe they could hook up the fuel pressure guage and watch it while the motor dies ... would be pretty interesting to see, wouldn't it?
Is there only one fuel filter on that year, Mike ... or is there a second one tucked somewhere that has not been found yet? I have seen stuff like this before on other vehicles. Or possibly a crimped fuel line somewhere along the line? ... Karen has been quiet today but I bet she's been working ... yup ... bet she has.
ALSO ... If they just hooked the FP up to 12v and watched it run, that can backfire on you. Those pumps work submerged and under load ... sometimes they appear to be good when tested in that manner but actually aren't. Maybe they could hook up the fuel pressure guage and watch it while the motor dies ... would be pretty interesting to see, wouldn't it?
and yes the pump can trick you keeping a pressure gage on it would answer that for sure
09-02-2009, 05:53 PM
#117
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on six different occasions on different vehicles
several people have checked the firing order or distributor position
some even checked by certified mechanics
and I re check and it was the firing order was of or back wards
or distributor was set in off
I want to get my hands on this thing so bad but it way to far for me
several people have checked the firing order or distributor position
some even checked by certified mechanics
and I re check and it was the firing order was of or back wards
or distributor was set in off
I want to get my hands on this thing so bad but it way to far for me
09-02-2009, 06:01 PM
#118
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Updated with as much info as I can remember so you only have to read this 1 post instead of going thru the entire thread...
Hi, I am new to the forums but I am at a loss and need some serious help. Almost 2 weeks ago my fiance and brother replaced a motor in an 88 cherokee with an 89 motor. Reason replaced high miles, getting hard to start, leaking oil, possibly head gasket needed replaced. Found a used motor with 80,000 on it guaranteed to run as it ran great before removed from vehicle.
It sounds like a really bad mower. It idles erratically, backfires into the throttle body, timing retards and advances itself.
I have had about 13 ppl out to check including a certified mechanic with no luck. At this stage I just want to know what the problem is and fix it. Enough was spent.
So far we have replaced/changed/tried:
From old working motor to new motor-
exhaust manifold
intake
head (rocker arms & push rods) yes it was torqued properly and not warped
distributor
TPS- from new motor to old motor -tested and adjusted 5.4v input, 4.42v output
stepper motor-from new motor to old motor
new parts:
plugs
wires
cap
rotor
distributor
MAP sensor
CPS
timing cover gasket
head gasket
fuel filter
ignition module
ECU-won't even start it
things we checked:
Gas is fresh
cat not clogged
compression good on all cylinders
all vac lines attached properly
timing chain in time by marks and 15 pins counted
correct firing order
flywheel not damaged
getting spark from all cylinders
fuel pressure test results-getting 31 psi with vac line and 39 without
fuel pump working properly and attached hose not rotted or damaged
leak down test on cylinders was good
*need to check timing with timing light*
Questionable:
new plugs are black and sooty
injectors spraying a stream not a mist
***after changing fuel filter (most recent thing done) sounds and runs better, but still backfiring when u give it throttle, runs bout 3 mins shuts off, starts back up immediately, bout 3 mins shuts off. Have to play with throttle before it takes it, still seems as if advancing and retarding itself.
paper spacer on CPS? didn't have 1 with the new 1
Harmonic balancer wobbling really bad but haven't found 1 to actually fit it yet. Need to take old 1 to store to match it up.
What am I not checking? Forgetting? What should I try now? Please help. Thank you to anyone who can help or give ideas.
Hi, I am new to the forums but I am at a loss and need some serious help. Almost 2 weeks ago my fiance and brother replaced a motor in an 88 cherokee with an 89 motor. Reason replaced high miles, getting hard to start, leaking oil, possibly head gasket needed replaced. Found a used motor with 80,000 on it guaranteed to run as it ran great before removed from vehicle.
It sounds like a really bad mower. It idles erratically, backfires into the throttle body, timing retards and advances itself.
I have had about 13 ppl out to check including a certified mechanic with no luck. At this stage I just want to know what the problem is and fix it. Enough was spent.
So far we have replaced/changed/tried:
From old working motor to new motor-
exhaust manifold
intake
head (rocker arms & push rods) yes it was torqued properly and not warped
distributor
TPS- from new motor to old motor -tested and adjusted 5.4v input, 4.42v output
stepper motor-from new motor to old motor
new parts:
plugs
wires
cap
rotor
distributor
MAP sensor
CPS
timing cover gasket
head gasket
fuel filter
ignition module
ECU-won't even start it
things we checked:
Gas is fresh
cat not clogged
compression good on all cylinders
all vac lines attached properly
timing chain in time by marks and 15 pins counted
correct firing order
flywheel not damaged
getting spark from all cylinders
fuel pressure test results-getting 31 psi with vac line and 39 without
fuel pump working properly and attached hose not rotted or damaged
leak down test on cylinders was good
*need to check timing with timing light*
Questionable:
new plugs are black and sooty
injectors spraying a stream not a mist
***after changing fuel filter (most recent thing done) sounds and runs better, but still backfiring when u give it throttle, runs bout 3 mins shuts off, starts back up immediately, bout 3 mins shuts off. Have to play with throttle before it takes it, still seems as if advancing and retarding itself.
paper spacer on CPS? didn't have 1 with the new 1
Harmonic balancer wobbling really bad but haven't found 1 to actually fit it yet. Need to take old 1 to store to match it up.
What am I not checking? Forgetting? What should I try now? Please help. Thank you to anyone who can help or give ideas.
09-02-2009, 06:02 PM
#119
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Year: 2004
Model: Grand Cherokee
Engine: 4.7L V8
on six different occasions on different vehicles
several people have checked the firing order or distributor position
some even checked by certified mechanics
and I re check and it was the firing order was of or back wards
or distributor was set in off
I want to get my hands on this thing so bad but it way to far for me
several people have checked the firing order or distributor position
some even checked by certified mechanics
and I re check and it was the firing order was of or back wards
or distributor was set in off
I want to get my hands on this thing so bad but it way to far for me