Okay everyone. So just like the title says, when I reach down to turn on the heat or ac, then engine dies. Has any one ever experienced this? Here is my scenario. I Just bought a 1997 xj. It is a 4 liter 4x4. Everything was great, but the coolant was dirty. I drained the old stuff out and put in distilled water and some Priest one Super flush. I drove it around for a couple of hours with the heat on, came home and drained the system. Installed strait distilled water and again drove around. Drained and filled with coolant and distilled water. I hosed everything off in the engine bay, but now, the Jeep runs fine, but as soon as I turn on the heat, the jeep dies? Anyone have any ideas? The heat and blower work, just not the engine?? Thanks!
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engine dies when heat/ac is turned on?
- Thread starter outracing
- Start date
Here is my issue in video form.
http://s1194.photobucket.com/user/OutRacing/media/VID_20150310_214551_151_zpskeorc5hx.mp4.html
http://s1194.photobucket.com/user/OutRacing/media/VID_20150310_214551_151_zpskeorc5hx.mp4.html
98NWCherokee
NAXJA Forum User
- Location
- Portland, OR
When you have the heater on, is it set to defrost? If so, I'd be suspicious that the bearing for your AC compressor clutch has failed and/or seized. Do you hear any belt squeal or noises when you engage the AC or heat in defrost mode? Try disconnecting the low pressure cut switch on the receiver/dryer near the passenger side firewall and see if the heat works now without killing the engine. That will prevent the compressor from trying to engage in defrost heat or AC mode.
roggom
NAXJA Forum User
- Location
- Northern Colorado
Shot in the dark, I would pull the blower relay as well, as the blower is on anytime the ac or heater is on. This problem did not start until you sprayed down the engine bay?
Alaskan89XJ
NAXJA Forum User
- Location
- Alaska
ROGGOM may be on to something.., hosing down engine bay..!
Ohio is cold, right? Do you park indoors when not using XJ? If I plunged my entire engine compartment crossing a stream in summer I would not be too worried, but where you live, water expanding, and turning into hard bits of ice.., would.
(In past times when I hosed down engine bay I made sure to put plastic bags over the distributor, and the carburetor, (removing air cleaner), and really secured them from intrusion of sprayed water.., otherwise.., weird happenings).
I do not want to imagine what water, then after.., when expanding into ice against old fragile wire connections/splices will do, (think expanding wedges), can't be good. I wonder if your 'hosed down' situation has compromised your fender fuse/relay matrix box thing, too. Many XJ'ers have had corrosion issues visible once entire relay box has been turned over. Water/ice under there can't be good either.
Have you tried wiggling various wires while having someone else try to start engine?
Have you refreshed 'all' grounds?
Could be a splice connection/connector that is shared by, and for your two indications, (if at all engineered to be so), are broken, or at least loose. I have no electrical diagrams/schematics to look at so I cannot help any further.
Ohio is cold, right? Do you park indoors when not using XJ? If I plunged my entire engine compartment crossing a stream in summer I would not be too worried, but where you live, water expanding, and turning into hard bits of ice.., would.
(In past times when I hosed down engine bay I made sure to put plastic bags over the distributor, and the carburetor, (removing air cleaner), and really secured them from intrusion of sprayed water.., otherwise.., weird happenings).
I do not want to imagine what water, then after.., when expanding into ice against old fragile wire connections/splices will do, (think expanding wedges), can't be good. I wonder if your 'hosed down' situation has compromised your fender fuse/relay matrix box thing, too. Many XJ'ers have had corrosion issues visible once entire relay box has been turned over. Water/ice under there can't be good either.
Have you tried wiggling various wires while having someone else try to start engine?
Have you refreshed 'all' grounds?
Could be a splice connection/connector that is shared by, and for your two indications, (if at all engineered to be so), are broken, or at least loose. I have no electrical diagrams/schematics to look at so I cannot help any further.
Last edited:
- Location
- Southern Maryland
Looks electrical to me. Could be in the dash wiring somewhere or might be external.
I don't have 97 can you post the settings for the dial?
Might try unplugging the blower motor, its a big power draw
I don't have 97 can you post the settings for the dial?
Might try unplugging the blower motor, its a big power draw
Alaskan89, right now it is in the 50's for temp. I do park in the garage. I am sure it is cause of something I got wet. I have checked every ground that I could find. I used my air compressor and blew out every connection I could fine. I unhooked the battery while I am at work. Maybe something will dry over the nine hours I am here.
what do you mean ehall? Like the settings?
I will start unplugging everything that is blower related and see if I can get it isolated.
what do you mean ehall? Like the settings?
I will start unplugging everything that is blower related and see if I can get it isolated.
mustang_gt_350
NAXJA Forum User
- Location
- pa
I Just revisited after many years away from the forum. Anyway. i saw this at the top of the posts and this is very close to what got me here in the first place but thats another post (i will post it in a few mins)
While looking for my problem i found this via google. and figured i would just toss it out there. Maybe its not a load problem, i wonder if its not killing the fuel pump and thats the issue i'm having.
http://www.naxja.org/forum/showthread.php?t=1096349
While looking for my problem i found this via google. and figured i would just toss it out there. Maybe its not a load problem, i wonder if its not killing the fuel pump and thats the issue i'm having.
http://www.naxja.org/forum/showthread.php?t=1096349
mustang_gt_350
NAXJA Forum User
- Location
- pa
I just updated my other post. But nope, still no luck.
Rick Anderson
NAXJA Forum User
- Location
- Lusby, MD
You disconnected the AC Clutch on the AC Compressor? The wire to the connector will run under the Pulley for the AC compressor. Some AC compressors will have additional connectors for pressure switches and sensors, usually the additional connectors are different parts of the AC system.
If the AC compressor was seized, it would cause the motor to stall when it is engaged. Certain modes will also turn on the AC even if you don't turn on the AC or set it to cool. Defrost for sure and any mode that is blended with Defrost, some Chrysler/Jeep will turn on AC when you select re-circulation mode.
I think in all XJ's the air blend doors are actuated with vacuum motors and the mode select switch just channels vacuum. The engine dies after you move the mode switch. Could you have a huge vacuum leak in the environmental controls or servo motors that kills the motor with a huge vacuum leak? I doubt it, I think the vacuum tube from the engine to the environmental control is small enough that even disconnected it won't create vacuum leak great enough to stall out the motor. But I would check it anyway, disconnect the vacuum hose and cap it off at the motor. Go back and see if it stalls out.
So 3 things that I can think of, that the environmental controls could cause the motor to stall. They've all been mentioned, and what you need to do, is disable/disconnect the source and see if the continues to stall. Once you'v isolated the cause you can fix it.
1.) Motor is stalled by physical resistance to it turning. The AC compressor, make sure that AC Clutch is disconnected, so the environmental control will NOT engage the AC compressor.
2.) Vacuum leaks within the environmental controls create a big enough vacuum leak to stall the motor. Disconnect the Vacuum Line at the motor and cap it off so no vacuum is being directed to the environmental controls.
3.) Electrical short drags down the voltage of the electrical system so much that it kills the PCM and other electronics in the vehicle. Previous posts made suggestions, the biggest electrical draw from the environmental controls is the blower motor, disconnect it, see if it still stalls. Look through your fuse diagram and pull the fuses that supply the environmental controls/blower motor as well.
Sidewinder CC
NAXJA Forum User
- Location
- Canton, Michigan
Thinking out loud...
The instrument cluster freezing just before the engine shuts down suggests that the PCM has lost power.
And this only happens when any selection is made on the HVAC Mode Selector (?).
If the engine starts and runs okay without HVAC selection I would think there's no blown fuse(s) in the PDC or JB.
Most fuses in the JB are associated with relay control coils and are powered when the ignition switch is placed to RUN.
Fuse 11 in your JB powers the ASD relay coil, Cooling fan relay coil, fuel pump relay coil, AC Compressor relay coil, and the PCM.
Most fuses in the PDC are associated with circuits powered from the battery or alternator and are routed thru the ignition switch. Fuses in the PDC power the JB.
It would seem that if all it takes to kill the instrument cluster/engine is to select HVAC you are removing power from the PCM. It would also seem that this action would blow a fuse, which it isn't (I presume) otherwise nothing would work associated with that fuse when not selecting HVAC.
All engine controls and HVAC controls go thru the PCM. Something is happening that the PCM does not like and is shutting down. A voltage is being introduced in to a circuit that shouldn't have voltage, such as a ground circuit. In '97 the HVAC control circuits were switched to Ground control, as opposed to Power control used in pre-'97 XJ's.
The AC Low Pressure Cycling Switch on top of the AC Accumulator and the High Pressure Cutout Switch are ground control devices connected to the PCM. They are the AC Switch Sense circuits. If you remove the connector from the Low Pressure Switch you have essentially shut off the AC system. You could try this to see if it makes a difference.
When you washed down the engine bay, how far did you go with the washing down? Did you get water in the PDC? Did you get water on any of the wiring harnesses?
Rick Anderson
NAXJA Forum User
- Location
- Lusby, MD
Good point, my suggestion to remove the power connector to the AC clutch will just prevent the Clutch from engaging the AC compressor (thinking a seized compressor might be causing the stall). The AC is controlled by the PCM and it will still be looking at the sensors for the AC regardless if the AC clutch engages or not. Disconnecting the low and high pressure switches will at least eliminate/identify the AC or electrical problem with the AC as a possible cause.Thinking out loud...
The instrument cluster freezing just before the engine shuts down suggests that the PCM has lost power.....
.... The AC Low Pressure Cycling Switch on top of the AC Accumulator and the High Pressure Cutout Switch are ground control devices connected to the PCM. They are the AC Switch Sense circuits. If you remove the connector from the Low Pressure Switch you have essentially shut off the AC system. You could try this to see if it makes a difference....
Sidewinder CC
NAXJA Forum User
- Location
- Canton, Michigan
OP,
Try this:
Refer to the Mode Selector pic below.
Before attempting engine start, place the mode selector to position 7 or 8 (heat modes), turn the ignition switch to RUN, but don't crank the engine. See if the voltmeter reads and the gas gauge reads. If they don't the PCM has shut down. If they do read, see if the engine will start.
If the engine starts, repeat the process with the Mode Selector in positions 9, 10,or 11 (AC modes). If the gauges don't read or the engine won't start the PCM has shut down and the issue is in the AC circuit.
.
Try this:
Refer to the Mode Selector pic below.
Before attempting engine start, place the mode selector to position 7 or 8 (heat modes), turn the ignition switch to RUN, but don't crank the engine. See if the voltmeter reads and the gas gauge reads. If they don't the PCM has shut down. If they do read, see if the engine will start.
If the engine starts, repeat the process with the Mode Selector in positions 9, 10,or 11 (AC modes). If the gauges don't read or the engine won't start the PCM has shut down and the issue is in the AC circuit.
.
Okay everyone. Here is the up date. Problem still not solved, and in addition, so the Jeep wouldn't start yesterday. I was able to pull it with another vehicle and dump the clutch and it would start. I figured this out only after killing the battery a few times. It runs, drives and idles fine, but will not start just by turning the key. Some times it will sputter like it wants to start, but just no go.
After pull starting, I pulled the 40 amp blower fuse under the hood and the jeep instantly died, same is if I turned the selector. To answer Sidewinders post, any position 5-11 will cause a no start/no run issue, but the gauges work fine. The gauges only freeze when the engine is running. Additionaly when the jeep is off, when turn the selector from any position to off, the fuel pump runs for 3 seconds or so and some relay(s?) click under the hood.
I'm banging my head against a wall here. Any one want to buy a red 97? Runs great for a barely running Jeep?
After pull starting, I pulled the 40 amp blower fuse under the hood and the jeep instantly died, same is if I turned the selector. To answer Sidewinders post, any position 5-11 will cause a no start/no run issue, but the gauges work fine. The gauges only freeze when the engine is running. Additionaly when the jeep is off, when turn the selector from any position to off, the fuel pump runs for 3 seconds or so and some relay(s?) click under the hood.
I'm banging my head against a wall here. Any one want to buy a red 97? Runs great for a barely running Jeep?
Sidewinder CC
NAXJA Forum User
- Location
- Canton, Michigan
Starting to look like a defective ignition switch (?)
Sidewinder CC
NAXJA Forum User
- Location
- Canton, Michigan
Okay everyone. Here is the up date. Problem still not solved, and in addition, so the Jeep wouldn't start yesterday. I was able to pull it with another vehicle and dump the clutch and it would start. I figured this out only after killing the battery a few times. It runs, drives and idles fine, but will not start just by turning the key. Some times it will sputter like it wants to start, but just no go.
After pull starting, I pulled the 40 amp blower fuse under the hood and the jeep instantly died, same is if I turned the selector. To answer Sidewinders post, any position 5-11 will cause a no start/no run issue, but the gauges work fine. The gauges only freeze when the engine is running. Additionaly when the jeep is off, when turn the selector from any position to off, the fuel pump runs for 3 seconds or so and some relay(s?) click under the hood.
Are you sure it was the 40A fuse for the blower? The last two 40 A fuses (below the blower fuse) are for the ignition switch.
I think you should take a look in your JB, specifically at connector C4. C4 is the large connector held on with a bolt. Remove the connector and check it and the JB for corrosion.
There have been a few XJ's with odd electrical problems attributed to a corroded JB.
See some pics.
Okay everyone. So here is an update on what I have done. I got the thing to start, the problem is still there. And dare I say, getting worse. Now, I can only start it once every few hours.
So I have tried pulling the blower relay. As soon as I pull it, the Jeep dies. Same goes for the blower fuse under the hood. (YES, I PULLED THE RIGHT FUSE.) It, as is should, dies also when I pull the "Start Run" fuse under the hood. I then pulled out the JB. Completely pulled it apart, layer by layer, I was surprised at how clean it was. There is nothing visually wrong that the naked eye could see.
I unplugged the blower itself, as soon as I did this, the Jeep died. I took apart the power distribution center under the hood. I was extremely careful. Every wire and every fuse is in good shape. No water nothing.
I even pulled apart all the knobs and inspected the circuit board behind them.
I am at wits end with this thing. Please, anyone, HELP!! :banghead:
Photobucket.com seams to be down for the time being. I'll post pictures as soon as I can.
So I have tried pulling the blower relay. As soon as I pull it, the Jeep dies. Same goes for the blower fuse under the hood. (YES, I PULLED THE RIGHT FUSE.) It, as is should, dies also when I pull the "Start Run" fuse under the hood. I then pulled out the JB. Completely pulled it apart, layer by layer, I was surprised at how clean it was. There is nothing visually wrong that the naked eye could see.
I unplugged the blower itself, as soon as I did this, the Jeep died. I took apart the power distribution center under the hood. I was extremely careful. Every wire and every fuse is in good shape. No water nothing.
I even pulled apart all the knobs and inspected the circuit board behind them.
I am at wits end with this thing. Please, anyone, HELP!! :banghead:
Photobucket.com seams to be down for the time being. I'll post pictures as soon as I can.
- Location
- Southern Maryland
Start inspecting engine harness, fuse panel, ECM, wherever. Might be easier to just replace the ECM from a known good jeep first. The fuse panel under the dash is known to get some corrosion especially from manual transmissions that drip clutch fluid there.
