2001 XJ will not start when temp is over 114 F
09-12-2016, 10:21 AM
#46
Junior Member
Thread Starter
Join Date: Aug 2013
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
Hi:
Update:
For the past couple of weeks the temperature was around 100-103 F I had no problem with the Jeep. On Saturday, 9/10/16, coming home the engine started to miss then stalled. I was able to pull to the side of the road. Temperature about 106 F. After 2 minutes wait the engine started and I drove home. The question is since the fuel pump is running, is it possible that the injectors stop working momentarily? If high temperature cause the problem then after the engine stops the temperature will further rise in the engine compartment. Then why will the engine restart after two minutes? Are the injectors directly controlled by the computer? Any suggestion?
Update:
For the past couple of weeks the temperature was around 100-103 F I had no problem with the Jeep. On Saturday, 9/10/16, coming home the engine started to miss then stalled. I was able to pull to the side of the road. Temperature about 106 F. After 2 minutes wait the engine started and I drove home. The question is since the fuel pump is running, is it possible that the injectors stop working momentarily? If high temperature cause the problem then after the engine stops the temperature will further rise in the engine compartment. Then why will the engine restart after two minutes? Are the injectors directly controlled by the computer? Any suggestion?
09-12-2016, 10:56 AM
#47
CF Veteran
I am just going to throw this out there, I read through most of the thread, and saw where you hit your CPS with a heat gun, but that isn't quite the same. If you have not replaced it, just replace it. its cheap and takes
09-13-2016, 10:20 AM
#48
Junior Member
Thread Starter
Join Date: Aug 2013
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
Hi aroudincircles: Yesterday I swapped out the ASD relay with the Fan relay. Let's see what happens provided the temperature goes up near 110 F.
What needs explanation is if the engine suddenly shots down due to high temperature in one of the component/system the temperature will increase in the engine compartment due to radiated heat and lack of air flow into the engine compartment. Then why will the engine restart after about a two minute pause? It does not seem logical.
P.S. What I need is my 68' Barracuda back with a 318 V8 engine giving me a much better mileage than my Jeep Cherokee and all that without computers. Also note I always passed the New Jersey emission test with flying colors which was one of toughest in the US at that time.
What needs explanation is if the engine suddenly shots down due to high temperature in one of the component/system the temperature will increase in the engine compartment due to radiated heat and lack of air flow into the engine compartment. Then why will the engine restart after about a two minute pause? It does not seem logical.
P.S. What I need is my 68' Barracuda back with a 318 V8 engine giving me a much better mileage than my Jeep Cherokee and all that without computers. Also note I always passed the New Jersey emission test with flying colors which was one of toughest in the US at that time.
09-13-2016, 04:41 PM
#49
CF Veteran
Check fuel pressure and also leakdown time. If good then look at the cam sensor and or crank sensor. Mopar only on these or you will be sorry later.
09-24-2016, 04:06 PM
#50
Junior Member
Thread Starter
Join Date: Aug 2013
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
Hi 97grand4.0:
The cam position sensor was changed out last year, but I will check the fuel pump since it has over 180K on it. When the engine stalls the pump still running but I am not sure how much pressure does it deliver to the header. I do not have the instrument to measure that.
After the engine stalls some time I can restart it, it runs about 4-6 seconds then dies. Pumping the gas pedal at this time has no effect on the RPM.
To change the subject, I was told by a car mechanic that I need to change out the track bar and all four shock absorbers.
I am getting a Moog replacement for the track bar but what should I get for the shocks, since I do not off road with the car nor do I heavy towing. Any suggestions?
The cam position sensor was changed out last year, but I will check the fuel pump since it has over 180K on it. When the engine stalls the pump still running but I am not sure how much pressure does it deliver to the header. I do not have the instrument to measure that.
After the engine stalls some time I can restart it, it runs about 4-6 seconds then dies. Pumping the gas pedal at this time has no effect on the RPM.
To change the subject, I was told by a car mechanic that I need to change out the track bar and all four shock absorbers.
I am getting a Moog replacement for the track bar but what should I get for the shocks, since I do not off road with the car nor do I heavy towing. Any suggestions?
Last edited by nhopa; 09-24-2016 at 04:16 PM.
10-16-2016, 08:56 AM
#51
Newbie
Join Date: Mar 2015
Location: New York
Posts: 20
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1999
Model: Cherokee
Engine: 4.0
Jeep starts cold but not while hot
Hi nhopa,
Curious if you were able to resolve your no start while hot issue. I've been following your thread & haven't seen a re-post for a month and have also been experiencing a similar issue on my 1999 XJ.
In my case my rig also starts up fine at the start of day while the vehicle is cold but once I come back to it and try and restart it it will not start up. I usually have to wait for the engine to cool down, sometimes 10 or 15 minutes before the engine will restart. No issues with shutdown while driving though. It started this summer on a very hot day while running my AC and only happened when the AC was on but now it always happens. I'm in NY so the temp gets nowhere near as hot as where you are in Phoenix, but it always happens now regardless of the temperature that's outside, even on the cool days we're now experiencing. So long as the engine has heated up she will hiccup, shake, and ultimately shut down till she cools off.
So far I've changed a rear bank post cat O2 sensor that had my CE light on and the only code I had, and my ignition sparks to each plug check out (cables/sparks/dist-cond only a yr old).
This week I'll be checking the fuel pressure (which according to what I've read in Haynes should be approximately 35 to 45 psi with key in on position but no cranking attempt, and 44.2 to 54.2 with Engine running and idling to see if my fuel pump sending unit is up to par. Btw both Pep Boys and Auto Zone rent the fuel pressure gauges & you get back your deposit upon ruturning them. If all checks out there I guess after that I'll check each of my fuel injectors to ensure they're working with proper voltage going to each.
Someone also mentioned to me that there is a known issue on jeeps with vaporization of the fuel in the fuel delivery bar when the engine is hot, since the bar sits on top of the hot manifold it then vaporizes the fuel in the bar before reaching each of the fuel injectors. They mentioned a solution there would be to wrap the fuel bar as well as each of the fuel injectors with a heat resistant tape to keep them cool and thereby eliminate the potential for the fuel vaporization issue.
Anyway, I'll post anything that I find on my end and hope you can resolve your issue.
Curious if you were able to resolve your no start while hot issue. I've been following your thread & haven't seen a re-post for a month and have also been experiencing a similar issue on my 1999 XJ.
In my case my rig also starts up fine at the start of day while the vehicle is cold but once I come back to it and try and restart it it will not start up. I usually have to wait for the engine to cool down, sometimes 10 or 15 minutes before the engine will restart. No issues with shutdown while driving though. It started this summer on a very hot day while running my AC and only happened when the AC was on but now it always happens. I'm in NY so the temp gets nowhere near as hot as where you are in Phoenix, but it always happens now regardless of the temperature that's outside, even on the cool days we're now experiencing. So long as the engine has heated up she will hiccup, shake, and ultimately shut down till she cools off.
So far I've changed a rear bank post cat O2 sensor that had my CE light on and the only code I had, and my ignition sparks to each plug check out (cables/sparks/dist-cond only a yr old).
This week I'll be checking the fuel pressure (which according to what I've read in Haynes should be approximately 35 to 45 psi with key in on position but no cranking attempt, and 44.2 to 54.2 with Engine running and idling to see if my fuel pump sending unit is up to par. Btw both Pep Boys and Auto Zone rent the fuel pressure gauges & you get back your deposit upon ruturning them. If all checks out there I guess after that I'll check each of my fuel injectors to ensure they're working with proper voltage going to each.
Someone also mentioned to me that there is a known issue on jeeps with vaporization of the fuel in the fuel delivery bar when the engine is hot, since the bar sits on top of the hot manifold it then vaporizes the fuel in the bar before reaching each of the fuel injectors. They mentioned a solution there would be to wrap the fuel bar as well as each of the fuel injectors with a heat resistant tape to keep them cool and thereby eliminate the potential for the fuel vaporization issue.
Anyway, I'll post anything that I find on my end and hope you can resolve your issue.
11-14-2016, 04:39 PM
#52
Junior Member
Thread Starter
Join Date: Aug 2013
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
Hi Cherokee Charlie:
Sorry for not responding sooner but got very busy. It seems to me that your problem is different from mine.
Since my last post I had the problem repeat itself twice. Now the temperature are down to the low/mid 80s.The engine starts stalling, loose power and the Jeep stops at the most inconvenient places on the road. Lucky thing is that the engine starts again after about 1-1.5 minutes. So the problem is intermittent. I noticed on some occasion that the engine runs about at 300 RPM but no power despite I am flooring the gas. To me this indicates possible fuel pump problem. Interestingly my code reader gives no indication of this or any other problems.
This is a very good forum, unfortunately the various problems and solutions could be located anywhere. I wish they had a matrix that would collect all similar problems in one place.
I got in the past couple of months lots of advise, like change this out and change that out. Rather than changing I opted for testing the components.
It looks like my fuel pump is located at the top of the tank, so I would have to drop the tank, but I am not 100% the problem is the fuel tank. Would it be possible that some clump of crud in the tank blocks the fuel flow through the filter and when the engine stops it settles back into the tank? I wish the engineers at Jeep?Chrysler would be a little bit smarter and provide and access cower in the trunk above the fuel pump assembly (like the Mercedes has it). Any feed back from any member is welcomed.
Sorry for not responding sooner but got very busy. It seems to me that your problem is different from mine.
Since my last post I had the problem repeat itself twice. Now the temperature are down to the low/mid 80s.The engine starts stalling, loose power and the Jeep stops at the most inconvenient places on the road. Lucky thing is that the engine starts again after about 1-1.5 minutes. So the problem is intermittent. I noticed on some occasion that the engine runs about at 300 RPM but no power despite I am flooring the gas. To me this indicates possible fuel pump problem. Interestingly my code reader gives no indication of this or any other problems.
This is a very good forum, unfortunately the various problems and solutions could be located anywhere. I wish they had a matrix that would collect all similar problems in one place.
I got in the past couple of months lots of advise, like change this out and change that out. Rather than changing I opted for testing the components.
It looks like my fuel pump is located at the top of the tank, so I would have to drop the tank, but I am not 100% the problem is the fuel tank. Would it be possible that some clump of crud in the tank blocks the fuel flow through the filter and when the engine stops it settles back into the tank? I wish the engineers at Jeep?Chrysler would be a little bit smarter and provide and access cower in the trunk above the fuel pump assembly (like the Mercedes has it). Any feed back from any member is welcomed.
04-17-2017, 06:26 PM
#54
Junior Member
Join Date: Jun 2013
Location: NE Missouri
Posts: 59
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee
2001 xj also fails when temps over 85 degrees
I've had this ongoing problem for 2 years now. have replaced the tcm, plugs, coil, cps, cleaned the tps, removed the cat, wrapped the fuel rail and injectors with insulating/reflecting tape.Nothing has helped. I spent $3000 on removing all the rust and having it repained two years ago. Anyone want it?
04-17-2017, 07:52 PM
#55
CF Veteran
Join Date: Aug 2011
Location: Nor-Cal Coast
Posts: 10,489
Likes: 0
Received 18 Likes
on
18 Posts
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
I spent a year with mine screwing up after sitting hot. Was so consistent that on a long trip I'd leave it running all day. Turns out in my case it was miss-routed wires, (to the lower Renix sensors). Sitting, the heat would migrate to (our Renix) heat shield over the manifold and cut into some wires, grounding them. Gave me fits for a year! Backfire blew the mouse nest out of the airbox, drove through the confetti! (no sign of the mouse
)
Had to tell that story here. Likely something expanding when it gets hot is your issue. Maybe till you find it a vented hood will help get you by?
* Holding the petal firmly on the floor while cranking will cut fuel to the engine while providing max air to help a flooded engine fire. Worth a try if you have fuel, spark and compression and it won't start.
Is that IAT two wire? That high voltage code might be a sign a wire is touching another somewhere.
Neat test for spark with coil packs there in post #40. I'd trust that way more than resistance checks.
)Had to tell that story here. Likely something expanding when it gets hot is your issue. Maybe till you find it a vented hood will help get you by?
* Holding the petal firmly on the floor while cranking will cut fuel to the engine while providing max air to help a flooded engine fire. Worth a try if you have fuel, spark and compression and it won't start.
Is that IAT two wire? That high voltage code might be a sign a wire is touching another somewhere.
Neat test for spark with coil packs there in post #40. I'd trust that way more than resistance checks.
Last edited by DFlintstone; 04-17-2017 at 08:11 PM.
04-17-2017, 09:31 PM
#56
Banned
Join Date: Oct 2016
Posts: 1,553
Likes: 0
Received 4 Likes
on
4 Posts
Year: 2000 and 1998
Model: Cherokee
Engine: 4.0
sensor resistance.
just an example, computer puts out a regulated 5v thru a 5 k resistor to a 5k sensor.comp reads 2.5 v.
as the sensor resistance goes up/dn the volts read from ,ex 1v lo to 4 v hi.
this tells the comp the value of whatever the sensor is monitoring,oil,water, air ,vac, throttle position,.....stuck hi or lo? bad sensor...or bcm!!
your res test is a good test of sensor..
oh, an idiot lite uses a switch, on or off,no variation from lo to hi
just an example, computer puts out a regulated 5v thru a 5 k resistor to a 5k sensor.comp reads 2.5 v.
as the sensor resistance goes up/dn the volts read from ,ex 1v lo to 4 v hi.
this tells the comp the value of whatever the sensor is monitoring,oil,water, air ,vac, throttle position,.....stuck hi or lo? bad sensor...or bcm!!
your res test is a good test of sensor..
oh, an idiot lite uses a switch, on or off,no variation from lo to hi
Last edited by nujeepguy; 04-17-2017 at 09:35 PM.
10-02-2017, 06:16 PM
#57
Newbie
Join Date: Oct 2017
Location: Valley Center CA
Posts: 8
Likes: 0
Received 0 Likes
on
0 Posts
Year: 2000
Model: Cherokee
Engine: 4.0L
I have read this thread and several others that have dealt with similar problems. This problem seems to be quite common and very hard to isolate and repair. I bought a 2000 Jeep Cherokee in March of 2015 and I have been able to fix all problems this jeep has thrown at me over the past two and a half years ( a bunch to be vague.) I have spent countless hours trying to fix this one and I am still coming up short. I don't like this problem because when the jeep fails it takes up to 30 minutes or more for the jeep to allow a restart and it happens in the most inconvenient times and my son and I are always expecting it to die while driving it. I live in So California with outside air temps rarely getting this hot, but it does seem that the engine will heat soak and after about 15 mins (even idling in my driveway) it will hiccup and sputter and stop running. Only after about 20-30 mins to cool down motor will it start (like nothing was ever wrong.) On some cool days with no AC running it will not have any problems at all, but we always expect the worst, and try to position the cherokee in a way that we can get out of the way of traffic if/when it dies. Its a real pain.
The vehicle overheated in June and my son was limping the vehicle up a steep grade to our home. Ultimately led to a blown head gasket due to lack of coolant due to small leak into #2 and #3 cylinder. he didn't check up on the fluids and caused a huge overheat. Honelstly it had just started consuming coolant and throwing codes for #2 and #3 cylinder misfires when this happened. Which has led to a few problems that has led to this real doozie of an issue.
Fast forward to Oct 2017 I have rebuilt the head, changed out more parts that I can remember, and I am left with a vehicle that will heat soak, sputter, die until engine cools down to a point it will start.
Just some of what I know I have addressed:
Replaced: CPS (Mopar), Crank position sensor (Mopar) Water temp sensor (Mopar,) Rebuilt ECU (short from fuel injector caused a failure in this when overheated,) TPS (Borg Warner,) ASD relay (not OEM,) Coil Pack ( from junkyard Cherokee and looks to be original,) #1 & #2 fuel injector wire harness (exposed wires touched and led to short on ECU.)
Possible Issue(s):
I will be changing the IAT next (from reading this thread it looks like many have recommended this.)
The ECU was rebuilt and bought online with a company that rebuilds and provided a warranty. I am concerned that this issue didn't present itself when they repaired and bench tested the unit. But the jeep runs perfect until it gets hot and hiccups and dies.
I have good fuel pressure (depress valve with lots of pressure) up until the point the engine dies. after it dies the fuel pressure is nothing until the vehicle cools down so I thought maybe the ASD. Once the vehicle cools down I hear the fuel pump but while its cooling down I don't hear it at all when I try to start the vehicle.
There are electrical plugs going to the Crank and Cam sensors that are charred and questionable but look to be in order. I have put a 3M tape around them to provide a bit of a barrier from heat soak. Also one CO2 sensor has a badly damaged plug on it that might be causing a short when hot. I disconnected it to see if I could bypass problem and it does not change anything.
Sorry for the long post, but I am hoping anyone can shed some light on this. Do faulty fuel pumps act in such a manner, intermittent and affected by engine heat?) I am thinking more electrical than a mechanical failure here.
Thank you,
The vehicle overheated in June and my son was limping the vehicle up a steep grade to our home. Ultimately led to a blown head gasket due to lack of coolant due to small leak into #2 and #3 cylinder. he didn't check up on the fluids and caused a huge overheat. Honelstly it had just started consuming coolant and throwing codes for #2 and #3 cylinder misfires when this happened. Which has led to a few problems that has led to this real doozie of an issue.
Fast forward to Oct 2017 I have rebuilt the head, changed out more parts that I can remember, and I am left with a vehicle that will heat soak, sputter, die until engine cools down to a point it will start.
Just some of what I know I have addressed:
Replaced: CPS (Mopar), Crank position sensor (Mopar) Water temp sensor (Mopar,) Rebuilt ECU (short from fuel injector caused a failure in this when overheated,) TPS (Borg Warner,) ASD relay (not OEM,) Coil Pack ( from junkyard Cherokee and looks to be original,) #1 & #2 fuel injector wire harness (exposed wires touched and led to short on ECU.)
Possible Issue(s):
I will be changing the IAT next (from reading this thread it looks like many have recommended this.)
The ECU was rebuilt and bought online with a company that rebuilds and provided a warranty. I am concerned that this issue didn't present itself when they repaired and bench tested the unit. But the jeep runs perfect until it gets hot and hiccups and dies.
I have good fuel pressure (depress valve with lots of pressure) up until the point the engine dies. after it dies the fuel pressure is nothing until the vehicle cools down so I thought maybe the ASD. Once the vehicle cools down I hear the fuel pump but while its cooling down I don't hear it at all when I try to start the vehicle.
There are electrical plugs going to the Crank and Cam sensors that are charred and questionable but look to be in order. I have put a 3M tape around them to provide a bit of a barrier from heat soak. Also one CO2 sensor has a badly damaged plug on it that might be causing a short when hot. I disconnected it to see if I could bypass problem and it does not change anything.
Sorry for the long post, but I am hoping anyone can shed some light on this. Do faulty fuel pumps act in such a manner, intermittent and affected by engine heat?) I am thinking more electrical than a mechanical failure here.
Thank you,
10-14-2017, 02:08 PM
#58
Newbie
Join Date: Jul 2016
Posts: 10
Likes: 0
Received 0 Likes
on
0 Posts
Year: 1995
Model: Cherokee
Engine: 4.0l SL6
Hello Sir;
I and my friend had a similar issue to regarding the engine getting hot and then cutting off. We both fixed our jeeps by doing the following:
First, I cleaned the throttle body and Throttle body position sensor (TPS). This sensor was filthy. Next I replaced the Intake Air Temperature Sensor (IAT). I noticed the old one also had carbon on it. Then I changed the Crank Position Sensor (CPS)-it was covered with a gunk.
My test drive was during the day (about 90 degrees). I drove up to big Bear mountain, from 1,500 foot elevation to 6,000 foot elevation. My engine temp got to 220-225 (could have gotten as high as 230) when climbing up the mountain. My engine did not stall.
Neither of us has had an issue since.
I and my friend had a similar issue to regarding the engine getting hot and then cutting off. We both fixed our jeeps by doing the following:
First, I cleaned the throttle body and Throttle body position sensor (TPS). This sensor was filthy. Next I replaced the Intake Air Temperature Sensor (IAT). I noticed the old one also had carbon on it. Then I changed the Crank Position Sensor (CPS)-it was covered with a gunk.
My test drive was during the day (about 90 degrees). I drove up to big Bear mountain, from 1,500 foot elevation to 6,000 foot elevation. My engine temp got to 220-225 (could have gotten as high as 230) when climbing up the mountain. My engine did not stall.
Neither of us has had an issue since.
10-14-2017, 02:25 PM
#59
CF Veteran
With 57 posts on this thread it might be time to start this on a new one.
The device you are looking for is called a fuel pressure gauge. Not possible to ts this without one. Then go find the various tests for a fuel pump.
The device you are looking for is called a fuel pressure gauge. Not possible to ts this without one. Then go find the various tests for a fuel pump.
10-14-2017, 05:05 PM
#60
Senior Member
Join Date: Mar 2010
Location: Alaska
Posts: 589
Likes: 0
Received 0 Likes
on
0 Posts
Model: Cherokee(XJ)
wire routing is a good suggestion, had a similar issue stallng and not wanting to start back up for 20 to 30 minutes, happened to be the cps wire sitting on the exhaust manifold didnt short untill it got hot.
marc
marc