1998 Ford Explorer Stalls When I Turn on the Air Conditioner

[CynthiaK]

Hi,

My Explorer keeps stalling and won't restart until I leave it for 2 to 3 hours - had to have it towed home last week.

Today I let it idle for about 10 minutes without the AC and it didn't stall. However I turned on the AC and about 5 minutes later it stalled and of course now won't start for another 2 to 3 hours.

I recently changed the fuel filter, cleaned the MAF and the IAC and today I checked the fuel relay and the fuel pressure at the rail and both are good. I have checked all the wires in case something was getting wet and shorting out from AC condensation but have found no issues.

I have read related issues on this forum but can't find my exact problem. Someone does suggest getting a new IAC for their problem, maybe that is my issue but the truck runs fine other than when the AC is on. Also, I don't get a Check Engine light.

Perhaps the temp sensor?

Does anyone have any idea what the issue could be?

Thank-you!

 

[Mbrooks420]

The temp sensor is usually a starting issue problem, I’ve never heard of it stalling a running engine. The Ac works and blows cold as it should?

 

[J_C]

I'd hook up a scan tool, check for pending codes but mostly to look at long term fuel trim. I suspect that once it's going PCM closed loop, it gets too lean to keep running, and possibly this in combination with the IAC valve sticking. You might also or instead have an A/C compressor that's about to seize up.

When you try to restart it, what happens? Does it crank fast? Does the belt slip on the A/C compressor pulley instead of rotating it? I would have a scan tool capable of live data ready for this event.

 

[Pete Deering]

Hi,

My Explorer keeps stalling and won't restart until I leave it for 2 to 3 hours - had to have it towed home last week.

Today I let it idle for about 10 minutes without the AC and it didn't stall. However I turned on the AC and about 5 minutes later it stalled and of course now won't start for another 2 to 3 hours.

I recently changed the fuel filter, cleaned the MAF and the IAC and today I checked the fuel relay and the fuel pressure at the rail and both are good. I have checked all the wires in case something was getting wet and shorting out from AC condensation but have found no issues.

I have read related issues on this forum but can't find my exact problem. Someone does suggest getting a new IAC for their problem, maybe that is my issue but the truck runs fine other than when the AC is on. Also, I don't get a Check Engine light.

Perhaps the temp sensor?

Does anyone have any idea what the issue could be?

Thank-you!

I experience my AC compressor seizing at a stop light, the engine stalled. Sound like the same thing.
So try too turn the AC clutch by hand, if it does not turn , then there your issue.

 

[CynthiaK]

The temp sensor is usually a starting issue problem, I’ve never heard of it stalling a running engine. The Ac works and blows cold as it should?

Yes, it gets very cold.

 

[CynthiaK]

I'd hook up a scan tool, check for pending codes but mostly to look at long term fuel trim. I suspect that once it's going PCM closed loop, it gets too lean to keep running, and possibly this in combination with the IAC valve sticking. You might also or instead have an A/C compressor that's about to seize up.

When you try to restart it, what happens? Does it crank fast? Does the belt slip on the A/C compressor pulley instead of rotating it? I would have a scan tool capable of live data ready for this event.

I did clean the IAC valve, it was a bit dirty but not bad.
It won't restart for 2 to 3 hours and then it does. It doesn't crank fast nor does the belt slip - it rotates the pulley.

 

[CynthiaK]

I am able to turn the AC clutch by hand, it is quite stiff but it turns.

Also, when I went out just now, the Explorer won't start and there is no pressure at the fuel rail whereas the other day there was 30.

 

[CynthiaK]

A new fuel pump was installed about 5 years ago, but perhaps that is the issue.
I have a code reader - no error codes but not a scanner tool.

 

[J_C]

If you have no fuel pressure turning the key to the run position (not trying to crank it yet), you do have a fuel problem.

If it doesn't crank at normal speed, I am wondering if you also have a sticking AC clutch as it should not be engaged when cranking the engine, and trying to power the compressor when cranking, could account for slower cranking. This assumes it cranks faster after the 2-3 hour wait, without having to charge the battery to get there? No fuel, won't slow down cranking.

 

[CynthiaK]

What should the temp sensor resistance be on a cold engine?

 

[CynthiaK]

"If you have no fuel pressure turning the key to the run position (not trying to crank it yet), you do have a fuel problem."
Today is the first time I have had no fuel pressure.

I don't ever buy Costco gas, but fueled up there the day before all these problems started......

 

[CynthiaK]

"If it doesn't crank at normal speed, I am wondering if you also have a sticking AC clutch as it should not be engaged when cranking the engine, and trying to power the compressor when cranking, could account for slower cranking."
Sorry, I misread the question about fast cranking. It does crank at normal speed.
Also, I unplugged the AC when cranking to test and it made no difference.

 

[donalds]

Have you tried cleaning your throttle body
Like actually removing it and cleaning it

An old air filter would cause These symptoms as well

 

[CynthiaK]

Have you tried cleaning your throttle body
Like actually removing it and cleaning it

An old air filter would cause These symptoms as well

I did not clean the throttle body but when I took off the IAC I looked at it and it didn't look dirty.
I will pick up a new air filter.

 

[donalds]

I did not clean the throttle body but when I took off the IAC I looked at it and it didn't look dirty.
I will pick up a new air filter.

It's the back of the throttle body plate
And throttle body boar around the bottom of the plate usually It's worth a look

 

[CynthiaK]

It's the back of the throttle body plate
And throttle body boar around the bottom of the plate usually It's worth a look

I will try that.

 

[CynthiaK]

Thank-you everyone for your responses!
They are greatly appreciated!

 

[donalds]

Thank-you everyone for your responses!
They are greatly appreciated!

No problem we love this stuff
remember keep asking questions if you need help
And when do you solve the problem come back and tell us how you did it

 

[Metalface]

On my 97, I had issues with stalling under any load or especially at stop while engine was running (when pressing the brakes, noticeably worse.)
Here are the parts I threw at the problem:
-First replaced alternator, but I knew I neeed one anyway. This still didn't fix the stalling issue.
-MAF sensor
-IAC
-Cleaned throttle body
-TPS
-New Intake Manifold Gasket (this job sucks, and requires total BS use of torx bits)
-New air filter, just for peace of mind
-Triple checked all vacuum hose connections + added hose clamps GENTLY where needed
-Cleared codes just in case then left battery unplugged to fully discharge for a ""fresh start""
-new spark plugs, + a shim on one that was cracked and clearly sent in with an impact (no problems to this day it has been years.)

And finally, the part that actually resolved the problem:

Ignition coil.... The cap was cracked, except, in the back. I could not see it, so it appeared fine. Problem got worse in humidity changes and after it rained. It was "generally reliable" on dry warm days. As soon as I replaced this part, I stopped having stalling problems. Every other part I replaced "helped" and helped cure a misfire, but, they did not solve the problem, until I replaced the cap for the ignition coil.
Worth checking! You never know. It could be so many factors.
I would change all these parts, myself, AKA fire the parts cannon at it. The thing is a lot of the time they are 1. not better than OEM/stock and 2. weren't necessary to replace. So you totally gamble with them and can sometimes, if they are bad out of the box, make the headache worse lol

Like adjusting a guitar neck for action/playability, there are a few steps in a *correct order* to avoid chasing your tail. I would go for the obvious first, and anything that has a service interval in the manual, first. I would also investigate live data with a reliable scanner in your OBDII port. Look for anything obvious or weird! And above all else, I've also learned to listen to all advice, and try all of it to a certain degree, even if my stubborn self thinks it's BS and I know better than they do.. LOL. There is a solid chance none of the things I suggested or learned from experience are your particular problem, but you never know. Please keep us updated!

Edit: Also, my AC compressor was not in great shape. The clutch made horrible noises (it has since worn quiet. and I will change it when it stops working or causes obvious drag.. it luckily wore in evenly and upon investigation does not cause drag. Truck sat for 6+ years and there was a surprising amount of corrosion in that area.) So that's worth thinking about too, like others said. The AC compressor works relatively pretty hard especially if you have a 4.0 V6. If the clutch is sticking I could see that bogging down the engine and causing stalls.

 

[CynthiaK]

On my 97, I had issues with stalling under any load or especially at stop while engine was running (when pressing the brakes, noticeably worse.)
Here are the parts I threw at the problem:
-First replaced alternator, but I knew I neeed one anyway. This still didn't fix the stalling issue.
-MAF sensor
-IAC
-Cleaned throttle body
-TPS
-New Intake Manifold Gasket (this job sucks, and requires total BS use of torx bits)
-New air filter, just for peace of mind
-Triple checked all vacuum hose connections + added hose clamps GENTLY where needed
-Cleared codes just in case then left battery unplugged to fully discharge for a ""fresh start""
-new spark plugs, + a shim on one that was cracked and clearly sent in with an impact (no problems to this day it has been years.)

And finally, the part that actually resolved the problem:

Ignition coil.... The cap was cracked, except, in the back. I could not see it, so it appeared fine. Problem got worse in humidity changes and after it rained. It was "generally reliable" on dry warm days. As soon as I replaced this part, I stopped having stalling problems. Every other part I replaced "helped" and helped cure a misfire, but, they did not solve the problem, until I replaced the cap for the ignition coil.
Worth checking! You never know. It could be so many factors.
I would change all these parts, myself, AKA fire the parts cannon at it. The thing is a lot of the time they are 1. not better than OEM/stock and 2. weren't necessary to replace. So you totally gamble with them and can sometimes, if they are bad out of the box, make the headache worse lol

Like adjusting a guitar neck for action/playability, there are a few steps in a *correct order* to avoid chasing your tail. I would go for the obvious first, and anything that has a service interval in the manual, first. I would also investigate live data with a reliable scanner in your OBDII port. Look for anything obvious or weird! And above all else, I've also learned to listen to all advice, and try all of it to a certain degree, even if my stubborn self thinks it's BS and I know better than they do.. LOL. There is a solid chance none of the things I suggested or learned from experience are your particular problem, but you never know. Please keep us updated!

Edit: Also, my AC compressor was not in great shape. The clutch made horrible noises (it has since worn quiet. and I will change it when it stops working or causes obvious drag.. it luckily wore in evenly and upon investigation does not cause drag. Truck sat for 6+ years and there was a surprising amount of corrosion in that area.) So that's worth thinking about too, like others said. The AC compressor works relatively pretty hard especially if you have a 4.0 V6. If the clutch is sticking I could see that bogging down the engine and causing stalls.

I will check the coil.