Welcome to the board, lots of good info can be found here.
You didnt say what year your Jeep and that does help us.
I will try and answer your questions as best as I can.

1) Your rear leaf springs are prolly shot, you can go to a bone yard and pick up so leafs out of a Dakota or Ranger or a Jeep and fix that, might lift the back up a bit but if you are going to be hauling ppl or gear then it helps to have the XJ a lil a$$ high.

2) I would test you TPS to so if it working right, also check the CPS too. The TPS is lockated on the throtle body and has to be adjusted when replaced. Chiltons repaire books have a good explonation on how to do this. The CPS is lockated on the driver side top of the belhousing, most of the time the conector is dirty and needs to be cleand.

3) I know how it feels to be driving around with crappy brakes, My rear drums are startimng to lock up on me about everytime I stop, not fun in the snow. YOu said that the brake fluid had boiled out, did you fush all the old burnt fluid out when you blead the brakes? If not then you still have crap in the fluid and mostlikely still some air. I keep a rule of thump when replacing brke parts I replace everything in pairs. If just one sides needs pads then I do both sides, if one caliper craped out both sides get replaced and the fluid gets flushed and new clean goes in. Rotors and pads do take a lil bit of time to seat but a few good hard stops and a few slow long stops seat them for me. Also did you clean off the rust protectent off the new rotor with BrakeClean?

4) The Emission light needs to be unpluged. Thats about the best way to do it, just take yo dash off and unplug it, they are controled by a timer box and most of teh time are just idoit lights that dont mean anything anyways.\

I hope I have helped some, Hopefully a few others can chime in and corect me if I was wrong, or have better ideas...Good luck and again welcome...andy

 

Never replace brake components individually. Always replace in axle pairs! Also, like he said, all new rotors come with an anti corrosion subtance on them (like oil) that needs to be cleaned off.

 

Hey Ryan, good to see another XJ owner!

1.) Just like Andy said, your springs are fatigued which doesn't always mean you see them visibly sag. Heck your front coils could be sagged a little up front too so you wouldn't notice. The Dakota leaf packs will give you about 3 to 3.5" of lift, so if you don't want that much just mix in a leaf or two. The Dakota leaf pack does have a thick overload leaf so I would try the 2nd leaf (the one right below the main) and the overload in your spring pack and see how that does. The overload will prevent you from bottoming out on the bumpstops.

2.)9 times out of 10 this is caused by a dirty or bad IAS (Idle Air Stepper) motor on the throttle body. You can remove it from the TB, use some electronics cleaner on it and replace it, but chances are the TB is also gunked up pretty good. It's easy to pull the TB off, remove the IAS and then clean it out really good, reinstall and see what happens. I had the exact same symptom of high revving at random and this cured it.

3.)If it's just the right front that is still giving you problems then you know the combination valve is ok. Like Kraby said always replace brake components in pairs. Right now you have all new brake components on one side and old worn on the other. Also make sure that the rotor is spotless and free of any oils. If the rotor got that hot you might want to replace the rubber line on that side as well.

That emissions light will never go out until you unplug that stupid little emissions timer box under the dash.

 

Hi again

Sorry about the late reply, alot of stuff going on, you know how it is..

I'm not really interested in putting any lift under the cherokee, i'd like to keep it as stock looking as possible, what could i do to beefen up the rear leaf pack with out any lift? It does have new(er) gas shocks on it, so i guess that rules out those as to why its bottoming in the rear

After another tank of gas through it since my last post, it hasnt started up and revved high on me lately in the last few days, now its doing almost the complete opposite and barely idling, its idling like right around 100rpm (stock cherokee tach isnt that exact, but its down in that area) and acts like it wants to almost quit on me if i turn the wheel while sitting still at idle.. its nothing drastic, but it is strange. I guess for a saturday project tomorrow i will pull off my TB and give it a good cleaning, i'm sure it probably hasnt been done in a while (if ever?) and i want to go ahead and replace my air filter with a K&N filter. After this, if it still acts funny i'll start testing out sensors and worrying about all that stuff.

I know i should have replaced both sides.. thats kind of a dum dum thing for me, but $ is a big factor, i am only 17 and can barely afford gas as it is, the brakes are working fine again, i never did clean rotor with anything before i slapped it on there, never even thought about it, after (like i already said) another tank of gas everythings seated and grabbing as usual. Now i guess i just count down until my left caliper dies.

My muffler bit the dust when a stump decided to crush it and it banged and clattered real bad at idle... it kinda angered me lol so i cut it off with a sawzall, and put a down tip on it about 6" after my catalytic converter. No more annoying buzzing clattering sound from the dead muffler, and the exhaust is much louder, but i kinda like it, i figured it would be annoying, but its got a nice rumble to it, i think i'll keep it like that...

where do i unplug the emiss. light at? under the dash? behind the dash? i guess i'll just start unplugging stuff tomorrow until it turns off.... heh

The specs on the jeep...

1990 Cherokee Laredo 4x4, red/grey twotone, 4door, 4.0L, commmand trac, auto, power everything, brand new 235/75/r15 rubber, looks great... i'm missing on of the bolt covers for my right rear wheel, and my horn cap button is gone, and the paint is starting to fade on the hood, other than that it's mint... i love it, its my 3rd vehicle so far and the greatest.

Thanks again for all the help, i'll try to get some pics of her up soon.... adios!

Ryan

<<haha (titties n beer) lmao

 

De-ja-vu. I have the same make and model and color XJ as you do, and have had simalar things (and questions) with mine over the years. As far as the rear: NAPA sells these helper springs, that you attach to the back of the leaf packs with supplied "U" bolts. While it won't lift the chassis any higher, they DO get stiffer the more weight you add to them. I sometimes haul Air freight out in my Jeep for extra $ for the boss. I put a set of the 1,200lb leafs on myne and it really helps out when I have a heavy crate in the back. They are adjustable too. I think I paid $30 bucks w/ my discount (I'm an ex employee, and I have friends still there.) They act kinda like a variable coil spring does, they get stiffer the more you flex on it. That should help that. They go on in under an hour. As far as your brake fluid, here's a tip: You can add DOT 4 instead of the DOT 3 fluid and you won't have the problems with fluid boiling as bad. (NEVER, EVER ADD DOT 5 to a stock system!)Most folks don't know that DOT 3 and 4 can be mixed together without any negative side effects. It has a higher dry boiling point, but still made out of diethilene-glycol.Speaking of the DRY boiling point, if there is any water in the system, the fluid is going to boil much faster too. Try to only buy as much brake fluid as you think you'll need at one time. Water will 'sneak' into the fluid and will ruin it. I'd bleed the systym again. If after you pump your pedal, it drops and you've got the bleeders closed, you've got a master cylinder going. Good luck, man...

 

hey if ya lifted it you wouldnt of smashed yer muffler

 

I'd like some more info on these add-a-leaf dealies... My 91 XJ has weak rear springs too, and I will be hauling a trailer with it from time to time (If I ever finish the dang racecar). I've got some decent rear shocks with coil springs over them (made as one unit - not the clamp on kind) but it's still not enough. So I can get springs from a Ranger out of a junkyard, or should I look for new Jeep springs? I don't want to lift it more than an inch or so.

All the additional leafs I've seen are made for an axle OVER spring setup, ot an axle UNDER spring like the jeep has.

For that matter - does anyone make fiberglass leaf springs for this thing? I can remember the fiberglass transverse leafs for the corvettes were the stuff to get back in the 90s, not sure if they are still legit or not...

Mike Harrington
gtc1990@hotmail.com
91 XJ Limited

 

dakota springs will work also, if i were you id get some dakot leafs from the junk yard and just play around mixing matching leafs untill you get the right hiegth and spring load. basicaly your only good option unless you lift it

if you dont wanna lift it any higher then yer gonna sacrafice ride quality for some damn stiff springs

 

I run 650 pound coilovers springs on the front of one of my RX-7s, which weighs MAYBE 2300 pounds. "Damn Stiff" is pretty subjective

I'll look for some dakota springs in the jy. Time to learn leaf springs I guess (grumble grumble).

MikeH
gtx1990@hotmail.com

 

its time consuming to do but its the best cause you can basicaly design yer own to yer needs. some want a really flexy suspension, some want a real stiff one, some want a in the middle, buying yer own junk yard leafs allows ya to make any of the three and maybe more

 

Yeah what Butcher said

...andy

 

i love lookin smart

 

I'm not saying that but ok

...lol...andy