joshsmommy642

I have a 97 Jeep Cherokee country 4.0 6 Cyl. I recently put on a new alternator (2nd one since Ive owned it, and a new battery, new fuel pump about two years ago). It needs both 02 sensors as one is bad and the other was hanging loose, got wrapped up and pulled completely out, wires and all. So today its pretty cold out, I had not driven the jeep in about 24 hours. It wont start, it acts like it wants to start but it wont catch and start up. It cranks and then it just makes these loud click clack noises so I let off trying the key. It has all of the fluids in it, and I can hear the fuel pump engaging. Any idea of where to turn? Im a girl and not one that is mechanically savy but I sure as heck will try. Please help me, my area is expecting 8-12 inches of snow. Thank You!!!

Larry's XJ

What??? 12" in Virginia?? Trade you for the -25 we had this morn.

BRB

Larry's XJ

If you have a battery charger put that on.
Clean battery terminals.
Did you try jump start?

CCKen

How long has it been since a tune up was performed (plugs, wires, cap & rotor)?

Try starting it with the gas pedal floored. If it does start you have raw fuel laying in the intake and cylinders.

If it won't start, remove the throttle body inlet tube, hold the throttle plate open, and squirt a little starting fluid in the throttle body while cranking. If it won't start, you probably don't have ignition. If it does try to start you may not have fuel even though you hear the pump running.

Pull the distributor cap up and take a look at the rotor and the terminals in the cap. See if they are ate up.

CCKen

Here's a pic of a '99 PDC. The '97 may be a little different.

Check the relay locations on the PDC cover.

Swap the radiator fan relay with the ASD relay and try it.

Check the fuses marked Fuel Injectors/Coil, ASD, and O2S Heaters (which is probably blown).

Make sure the rear O2S wiring is isolated from each other and the chassis.

.

joshsmommy642

Thank you for the suggestions. I am going to have someone try a few of those things that sound unfamiliar to me. I did put a charger on it earlier just to be sure of the battery and it was charged. I also have tried starting it with the pedal to the floor but it didnt start.

Larry's XJ

If/when you pull dist cap, if there is crud on the six lugs clean it off. Lightly clean rotor end/metal with fine sand paper or emery board. Look for cracks in cap and/or moisture condensation. Check that wire from coil to cap is clean and tight.

If cap does have crud cleaning will get you by for a bit, but a full tune-up should be in your future.

Have you pulled any of the plugs?

digitaljohn

Oh man. I just dealt with this on a 95' Sport I got very cheap, because the previous owner could not figure out this problem. I had the rapid CLACK CLACK CLACK CLACK after leaving the key turned as well. If you let the noise go until it finishes, your Jeep will start.. but it was taking mine as long as 15-20 minutes. My engine would turn over all day in the meantime, but would only ever catch if I had waited for the clacking to finish.

With some luck on Google I figured it out pretty quickly. The problem was the ECU. I had a bad capacitor or two (or three), and the computer had to warm up before the Jeep would start in the super cold. I realized mine was the problem after I tried warming up the ECU with a blow dryer one cold morning, and it started right up without the wait or the noise. I guess this is actually a fairly common problem. The ECU is the black box with vents on the right side of the engine bay, if yours is located like mine.

You can fix this yourself! Find someone handy enough with a soldering iron to replace 3 capacitors if you can't do it. You need 3x 220 uf 35wvdc capacitors. I got them at Radio Shack. Removing the silicon on the ECU board is a bit tedious, but overall the project is very easy. Total cost to fix my Jeep was $1.82.. and I got my Cherokee almost a grand under blue book for this problem.

Follow this tutorial and you'll be golden: http://www.jeepforum.com/forum/f12/c...rs-ecu-492597/

Of course, you could also replace the entire ECU if you'd like, but it'll cost a lot more.

I believe there's about a 99.9% chance this is your answer.

DFlintstone

Mommy, I'm on a supper role of being wrong every time..so John, the hair dryer on the PCM is a nutty idea, that could never work. OK mom, now try the hairdrier idea...(only)

Then listen to ken!

digitaljohn

Hah, it does sound nutty. Could always be wrong, but I read a lot about this problem and all the signs are there.

It happens/gets worse with colder temps, the engine will turn over continuously but not catch and there will usually be an accompanying rapid clicking noise. If you ever have those three specific symptoms together, always check the computer.

You can diagnose with 5-10 minutes of a hairdryer on the computer to see if it starts right up after. You can also leave the key turned and give the Jeep 10-15 minutes for that clicking noise to stop, and see if it starts after. If doing either of those two things starts your Jeep, the computer (and more specifically, its 3 capacitors) are very likely the problem.

I suppose you could also pull the computer (very easy) and inspect the capacitors. 2 of the 3 on my Jeep's were visually oozing a white/gray substance from the top of the caps. The board is inside of a vented plastic housing, encased in silicone. Pretty easy to remove and replace. The capacitors are the round things that stick out above the silicon. You should be able to tell if they're blown without digging into the silicone. To replace them, you will have to remove the silicon in those spots on both sides of the board, resolder the caps and then re-seal the board.

Here's a pic of the board from that tutorial I linked to in my previous post, showing how the tops of the caps stick out above the board. If they are bad they might be deformed or oozing a small amount of a strange substance.

joshsmommy642

I am still trying to figure out whats going on. Once the extreme cold and snow left I tried starting the jeep and it started. I drove it around the neighborhood and it drove fine with the exception of some initial sputtering but I think that is caused since it needs both O2 sensors replaced? I started it the following day and it started. Now today I try to start it and it did, drove it around the corner, stopped at a stop sign and it shut off...no sputter, no noise, just died.

Dhruva Sanchai

Hello, i have a similar problem. Jeep cranks over but doesnt start unless i step on gas a bit. Need to press gas pedal for a minute to prevent it from dying at idle rpm. Problem completely disapears when warm. What should i do?