89 Cherokee 4.0

[davbell22602]

Do ya have enough tension with alternator on the engine belt? Belt might be too loose.

 

[davbell22602]

Did ya buy the right alternator for it? Some vehicles have 2-3 different ones for the same the engine.

 

[exotion]

You could also look at all the small hoses (rubber tubing) that connect to the fuel system and the distributor. If those are original (1989) they could be rotten and touching them while you worked on the alt could have opened up a crack.

If you haven't touched the timing, I wouldn't mess with that until you exhaust other possibilities.

It also wouldn't hurt to sit down with the manual (I like Haynes -- have used them for years) and read the sections on the fuel system and the ignition. I'll bet the answer is in that book.

Is it really idling at 150 rpm? That seems so low.

Excatly it sits.down the and bounces between 150 to 500 I haven't touched timing and am a little intimated by it although in the haynes which in the troubleshooting section it breaks it down to the different symptoms and all the different symptoms point to ignition timing or vacuum I haven't cleaned the throttle body I wanted to but the imbesile who owned this thing previously stripped the three torx head screws holding the air intake tube to the throttle body. I could carefully pull the tps and clean it and the egr has my attention now it shows sake symptoms I am having but so did the plugs wire caps rotor ... I have a bad feeling carscw is right with the timing and I don't have the tools or knowledge to deal with it and I don't really wanna spend a lot of money at a shop

 

[exotion]

Do ya have enough tension with alternator on the engine belt? Belt might be too loose.

Belt feels good and its the right alt voltage is good on dash and napa hooked me up this is the third one I've put in I am pretty sure they are unrelated at this point. I disconnected the wires and clamped them together to reset computer while I trickle charged the battery about 30 mins. When I sit in I can turn on all my acesorys and then turn them off and the voltage goes back to normal

 

[Mike88se]

So my jeep has some new problems and I'm having trouble figuring it out this time. So alternator went out and I replaced now probably unrelated the car barely idles maybe 150 rpm Sometimes stalls while I'm .looking in there. Lots of hesitation on acceleration no power and back fires randomly quietly inside the engine bay. I have replaced plugs wires cap and rotor cleaned distributor check everywhere for vacumn leaks ran heavy dose of seafoam through air intake to clean throttle body and chambers. I am thinking egr valve or tps but am tired of throwing money at it. Also thinking timing but don't have tools to test or fix that I know this is a lawn mower forum but I'm stuck and hopefully someone has something for me to try

I owned a couple of XJ's but it was a long time ago. I did do all my own wrenching so maybe I can recall something. Start at the beginning. Were these problems present before you replaced the alt?
EGR is easy enough to test. Pushing up on the diaphram should do it. There's probably also a EGR solenoid tho. An old TPS is basically an on/off switch. Use a meter to test for continuity at closed throttle and open throttle. Should be continuity at closed and then break when its opened. Timing... valve timing could be off a tooth if the chain stretched but not likely. If you didn't touch the distributor hold down then ignition timing should be same as it was. Like somebody mentioned it sounds like a vac/intake leak. Isn't there a rubber intake boot? Check that.
If it ran good before recheck all your steps. Oh and if you ran 3 cans of Seafoam through the intake you may need a new o2 sensor or even a cat convertor sometime.

 

[exotion]

I owned a couple of XJ's but it was a long time ago. I did do all my own wrenching so maybe I can recall something. Start at the beginning. Were these problems present before you replaced the alt?
EGR is easy enough to test. Pushing up on the diaphram should do it. There's probably also a EGR solenoid tho. An old TPS is basically an on/off switch. Use a meter to test for continuity at closed throttle and open throttle. Should be continuity at closed and then break when its opened. Timing... valve timing could be off a tooth if the chain stretched but not likely. If you didn't touch the distributor hold down then ignition timing should be same as it was. Like somebody mentioned it sounds like a vac/intake leak. Isn't there a rubber intake boot? Check that.
If it ran good before recheck all your steps. Oh and if you ran 3 cans of Seafoam through the intake you may need a new o2 sensor or even a cat convertor sometime.

I seafoam regularly I replaced 02 sensor last year and I had cat tested and its good I'm going to cut it out anyway assuming this thing gets running I know nothing of egr valves I've read alot and online makes it sound simple but the haynes makes it sound like I need to almost pull the engine to check and some vac tester equipment

 

[mullins87]

Are you certain the battery is good? What about the cables? You disturbed the cable going from the alternator to the battery when you changed it out, you could have also disturbed the other battery cables in the process. Jeeps are notorious for running poorly or not at all when the battery appears fine. Your battery could be weak, also could be the reason the alternator crapped out.

 

[exotion]

Are you certain the battery is good? What about the cables? You disturbed the cable going from the alternator to the battery when you changed it out, you could have also disturbed the other battery cables in the process. Jeeps are notorious for running poorly or not at all when the battery appears fine. Your battery could be weak, also could be the reason the alternator crapped out.

Alt went out because of bad bearing that has been whining for about a year lol I tested battery its good besides I left it on the trickle charger for about 24 hours after draining the battery on the tow home. I checked all the wires to and from alt and battery haven't gotten a chance to get in it today my wife wants me to take it .to a shop ugh .....

 

[Mike88se]

Haynes is great but not perfect. You shouldn't need to have special tools to check the EGR but I don't think that's the problem anyway. I know they go out but I've never had it happen. And when a vehicle runs good til after you work on it it's almost always something you can find by retracing your steps. I'm still thinking a vac line or sensor connector or intake leak. Might want to check the sparkplug cable routing just to be sure.
This site might be useful: Jeep Cherokee XJ EGR Function Testing service manual download | Car Service Repair Workshop Manuals
That site also mentions a computer relearning thing when the battery is disconnected. I don't recall any relearning when I disconnected a battery but you never know from one car to the next. Good luck!

I seafoam regularly I replaced 02 sensor last year and I had cat tested and its good I'm going to cut it out anyway assuming this thing gets running I know nothing of egr valves I've read alot and online makes it sound simple but the haynes makes it sound like I need to almost pull the engine to check and some vac tester equipment

 

[exotion]

Haynes is great but not perfect. You shouldn't need to have special tools to check the EGR but I don't think that's the problem anyway. I know they go out but I've never had it happen. And when a vehicle runs good til after you work on it it's almost always something you can find by retracing your steps. I'm still thinking a vac line or sensor connector or intake leak. Might want to check the sparkplug cable routing just to be sure.
This site might be useful: Jeep Cherokee XJ EGR Function Testing service manual download | Car Service Repair Workshop Manuals
That site also mentions a computer relearning thing when the battery is disconnected. I don't recall any relearning when I disconnected a battery but you never know from one car to the next. Good luck!

Ya I did the computer relearning ill look at the egr tom if it is vac or intake I can't find it like I said I emptied 3 cans of carb cleaner looking