Wierd problems.. I need help, please

I have a 1989 Cherokee Laredo 4.0L straight 6 4x4. I get a nasty shake about 45-55 mph when i let off of the accelorator it goes away, its a whole body shake but not felt in the steering. It runs hot when i'm in traffic it overheats, and theres a voltage problem when i use anything electrical in any combination such as radio/headlights, headlights/fan any combination of things. I have replaced the altinator, plug wires, plugs distributor and button in distributor and battery cables and still have a voltage drain. I'm just starting on the cooling system so i havn't replaced anything except the thermostat. I hear the electric rad fan come on when i think to listen for it. O2 sensor has been changed. My stearing wheel is loose at the pivot joint even when locked in place

the shaking started the day after i had the injectors replaced, my #1 injector was leeking so i figured that i might as well replace all of them while it was getting done... drove somewhere between 25-30 miles and it drove fine. got home shut it off and next day it started the shaking. and it only shakes at the above mention speed range but goes away when i let off the accelorator or i am below 45 or above 60


Really need some help being pointed in the right direction.

*edit- got the cooling problem fixed. i tried burping, it worked for a little then it started again ended up changing all the coolant lines and it hasn't got near 210 yet (3wks and counting) thanks for all the help.

Let's take this one at a time.

Nasty shake. Search the forum for "death wobble". Could be as simple as tire balance or up to ball joints. Lot's of things can cause the shake. My '88 needed a new steering damper.

Overheat. Assuming it cools down when you start moving again, you could be low on coolant. Search the forum for "burping" and make sure you're not low. Could also need a good flushing. Fan clutch is another cause of low speed overheating.

Voltage problem. Could you be more specific? Do you mean "low voltage" or does the battery drain when you're not using it? Check the grounds on the engine block and firewall.

voltage problem... drains when i use anything more then the radio at the same time. like if i run the radio and the headlights the volt meter drops.

my tires are balances and the ball joints are good

Dropping is normal. How far does it drop? Have you verifed the voltage at the battery with a meter? The dash gauge is not that accurate.

Shaking is caused by lot's of things. Bad steering damper, track bar, tie rod ends, wheel bearings (the list goes on).

volt gauge can and has dropped almost to the red when i wasn't paying attention but comes back up if i turn the fan or whatever else is running off and my lights do dim when this happens. last time i had it checked on a meter it was good

thanks for the advice

Cooling - after you check what Saudade suggested, make sure that your radiator doesn't have corrosion in it. The reduced airflow at low speeds might keep it from having sufficient flow. The fan's coming on, and it cools down so I'd think that air circulation and the water pump aren't the issues. I'd bet that a 1989 model has enough mileage and just enough corrosion to make the cooling system weak....and XJ's are known for having marginal cooling anyway.

Vibration - you said it started after you replaced the injectors, so....go back and make sure they're all in correctly and that there aren't any loose connections. If there was something gritty in the fuel system that you dislodged when changing them, then one of them may be clogged.

Voltage - it's normal for older vehicles to show a discharge at low engine speed with a heavy load. Does it move back to positive when you start off from the light or wherever you were sitting? As long as it shows a positive charge while driving at speed, you should be ok -- you didn't mention that you had the battery discharge....

With a load, electrical, your alternator should not drop below 12 volts if your running everything. If so you may have a bad alternator, this has happened before, where did you purchase the alt. from. Recommend NApa, little pricey, but they work well. I have an 89 4.0 and even with my stero cranked and all my lights on( off-roads too) my voltage is still in a normal range (12.7-13.5). Take your alt. off and have it bench tested. I have the original alternator (150K).