My thought is that many of the other sensors may be coming 'out of whack' and combining that with a marginal CPS could yield a stall under certain conditions.

Can you define high altitude? Our 93 4.0 never misses a beat in Colorado, even at 12,000'+.

What kind of stall is it? Sputter or like the key was switched off? Any smoke on restart? Color?

 

"higher" altitude...around 4-5 k feet. Out just turns off like the key was shut off. No smoke on restart

 

Codes? Also besides the map, the fuel pressure regulator needs to react to the reduced pressure. Anyway you might check your fuel pressure just on GP. Btw, I think the high altitude CPS for a renix is just positioned in the bracket to give a little more advance, as TJ pointed out.

Newer (OBDII) models - Put the key into the ignition, push down the odometer reset button, then turn the key to RUN with your finger on the button - and then release the button. The odometer will go through 1111111 through 999999, then display the car's serial number. It will then show the error codes (it might show them starting with P). If this method does not work, try the OBDI method.

 

Unfortunately this will not work for his 98. All he will get is a "cluster test" when he tries that. Sometime in 97, using the above technique only worked from 1996 to somewhere mid-1997, when Chrysler made a change and at that point through 2001, the only way to get codes is through a code reader or a scan tool.

My gut feel on this one is still crank sensor.

 

i have to agree with tjwalker - sounds too much like a crank sensor issue to be a coincidence. i would suggest you start with replacing that component first.

You can also test it, but it's not always a definitive diagnosis of whether it's working properly all the time.

 

Thanks to all for your input. I will indeed check out that crank sensor although I am a bit confused.

One guy is talking about the CPS (camshaft position sensor) and now another talks about the Crank sensor...should I just replace both? Or does this sensor work for both the camshaft and the crankshaft?

 

they are different sensors, technically CPS is cam sensor, but in jeep speak we all mean the crank sensor (CKPS?). Just replace the crank sensor cam sensors rarely go bad

 

My thanks again TJ for taking the time...... Guess that puts (most of the), "On-board Diagnostics II", right their with "Jumbo shrimp" , and "military intelligence"

Not disagreeing with anyone, but myself I might check for codes and the fuel pressure before I bought anything. Things you might do anyway.

 

Thanks again Gentlemen, I will report back with any findings I may come across.

 

Hey guys i'm new to the forum, I got my 1998 XJ limited last week. Ive driven it like 600 miles since I bought it, all premium gas. Yesturday I headed up to get a mas tree and right at 4000 or so my engine just started cutting out.....It wouldn't even idle enough to turn around, had to restart it three times to head back down the hill, and full tank of gas BTW. As soon as I dropped below 3200ft no sign of this issue. Any Ideas?

 

HIGH is a relative term. To the best of my recollection, my `97 has never been below 5,000 feet in its entire life. Likely manufactured at a lower elevation. For the last 14-years it's been at 8500-feet and I only go up from my house. Regularly drive to 12,000 feet and higher. Never had any stalling problems.

 

It was the "crank shaft position sensor". I replaced it and went wheeling! 6000 ft no problem. Thanks for the input guys.

 

I have a 96 XJ and have been experiencing engine stall at 3400' to 3600' in elevation. I have to si for about 20 or 25 minutes and then it will finally start again and then I never have another issue the rest of the day. I live at about 200' and go up to 6000' or 7000'. It only stalls once and with no indicators that anything is wrong. I'll give the csps a check but would like to know if anyone has any other ideas?

 

cuts out instantly or coughs and dies?

 

The engine cuts out instantly. I have a new water pump and thermostat and fairly new radiator. It acts like it has overheated but the temp is normal. When I try to restart it reminds me of vapor lock. As I said I have to let it sit for 20-30 minutes then it starts again.