Hey guys. I havent been on in a while to busy with life right now.
but iv been having problems with my 93 Country.
A while back maybe 3 months ago it started coming up with over heating problems and shutting off on me, then it wouldent start till minutes lator. i had fixed that problem by changing the Thermostat and hooking up a new Elec Fan. But the the other day i was riding and while i gave it gas it made a big POW noise. like an explosion idk if it came from the exhuast or it came from the engine, seconds after it happen it shut off and i started it back on then it shut off minutes lator. After that day it has been cutting off on me a while after i start it, it even shuts off if i start driving it after like 10 min. every time i start it up it just shuts off and wont start till 3 hours lator maybe even more. I have changend the thermostat, new elec fan, new oil pressure sending unit, new fuel pump. fuel filter, new coil and new ballast resister. i am going crazy i dont know whart is going on. i need this thing up and running by 2 weeks. Please Cherokee Forum HELP ME OUT!

 

Hmmmm... what about your sensors? CPS, TPS
Also have you done a BASIC tune up lately? I.E. spark plugs, distributor cap and rotor, plug wires etc..?

Good luck man!

 

If the engine turns but dosn't start, it can be only two cases. Either fuel missing or power missing.

Did you smell the fuel while trying to start? if yes, check the electric. distributor, cam sensor (!!!). I dont think of the sparks and spark wires, because even with 5 cylinder it would start.

If you did not smell the fuel, check the pump first and then check if you have a blockt fuel pipe, in filter and the pipe itself.

This is for the case that the engine has no bigger mechanical defect. When the engine was on, it run and idel nicly, right?

 

I mean yeah the engine start up and runs perfectly fine. The problem is, after the engine is ran for about 10 min, even if its stopped and ideling, or running at normal RPMs it still shuts off and doesnt start back up till about 3 or 4 hours have passed. after 3 or 4 hours have passed it starts right back up with now problem, it just shuts back off again. i can do this process over and over again it will still start up and shut off, start up and shut off. its so weird, i know i am getting fuel becuase its a brand new fuel pump and fuel is getting to the engine. it has a brand new coil with ballast resister so its getting elec. am just not sure if its getting elec when it shuts off becuase when it shut off once i checked if it had elec in one of the spark plug wires and it did not. thats why am clueless, why does it run perfectly fine for 10 min then shuts off and wonr start back up till 4 hours past???

 

Realy weird!
But the posibilities geting smaller. The cam sensor (below the oil filter in the short block) controls the ignition timing. When to fire which cylinder. The cam sensor is an "pin" which gets turned from the cam shaft and therwith he knows where is the crank shaft / piston position.
You can check the system from the cam sensor to the spark plug by pulling an spark plug, put it back to the wire and holt it against the block / frame ( the electrical ciruit must be closed again. If you hold it in the air, it won't give any spark) and then try to start the engine.

Do this when the engine is "OK" and also when it won't start.

I have no idea why this should happen after 10 Min. Normaly the cam sensor either works or don't, but the cam sensor also turns the oilpump. Maybe it comes from this side!!??

 

The same thing was happening to me, left me stranded 3 seperate times. Ended up being my CPS. After replacing the CPS I didn't have the issue. Then I had the radiator flushed, because it stunk something horrible.

 

next time it shuts down check for spark and injector pulse

 

Check the fuel pressure yet?

 

You can check the injector signal in this way:

- Take an volt meter vor measuring up to 20 volt
- connect the black end (negative) of the meter at the frame or the batery minus
- turn the key to start, but don't start the engine (last step below) lights in the dash shall come on
- check both wires at the injectors
- 1 shall have 12 -13 V and the other 0

the one with 0 is the one which later tells the injector when to inject and it only give any volt when the engine is runing. The other is always on 12-13V as power supply.

If this wire gives no impuls to the injectors, you can have fuel pressure as much as you want, because the "valve" is closed!

But you have to smell fuel when trying to start for more then 3-4 times!!! if this is not the case, you have no fuel!!