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Night_Wolf
02-03-2012, 02:57 AM
Hey Guys/Gals I am trying to help my buddy fix his Jeep Cherokee its a 94 with the 2.5L and a 5 speed and it runs fine but has a really difficult time starting. We replaced the ignition coil and fuel pump, as well as the crank position sensor. One thing I've noticed is that the fuel pump and auto-shutdown relays under the hood click like crazy (like morse code) and then they slowly begin to click less and less and eventually stop. After which the truck will start after a couple of tries to turn it over. Any idea what will fix the problem?

Also, the dummy lights only come on after the clicking from the relay ceases and then they shut off like normally after they come on.

Eric Barrera
02-03-2012, 03:02 AM
Cold start injector?

85gtsblackman
02-04-2012, 05:24 AM
it is a crysler, good luck fixing them electric gremlins

Car_Barn_Bandit
02-04-2012, 05:47 AM
it is a crysler, good luck fixing them electric gremlins

Saw this in a parking deck the other day:

http://www.celicatech.com/gallery/files/9/4/1/6/331994_144871308964932_100003261907632_178739_1586 558243_o_481344.jpg

Looks like the Lord of the Sith drives a Chrysler.

Eric Barrera
02-04-2012, 06:04 AM
Saw this in a parking deck the other day:

http://www.celicatech.com/gallery/files/9/4/1/6/331994_144871308964932_100003261907632_178739_1586 558243_o_481344.jpg

Looks like the Lord of the Sith drives a Chrysler.


that explains so much

dte
02-04-2012, 06:11 AM
Have you checked that all your grounds are clean and secure?

Car_Barn_Bandit
02-04-2012, 07:26 AM
I seem to recall the starter solenoids always burning out on Jeep Cherokees. Have you had that part tested?

Sent via Imperial Comlink

Night_Wolf
02-04-2012, 07:26 AM
Have you checked that all your grounds are clean and secure?

Yea I replaced the terminals cause they were corroded and cleaned the grounds the best I could, I was going to try and throw on an extra ground or two this weekend to see if that helped the problem


it is a crysler, good luck fixing them electric gremlins
And yes I hope this isn't the problem....

temperacerguy
02-04-2012, 09:45 AM
it is a crysler, good luck fixing them electric gremlins

+ 20million.

They are by far the shittiest electrical system known to man.... and I have worked on 60s lucas electronics!

Window regulators, power door locks, relays, damn near everything is a huge piece of shit...

The factory fuel pumps on these don't hold pressure very well if they aren't running, so every time you turn it on, you have to let the fuel pump build pressure before they start. combine that with the fuel pump relay being a POS, my buddy has a "one-two" motion to start his Cherokee. He puts the key in the ignition, then bumps the starter, he waits a second and hits the starter again. I noticed this a few times, and his response "It never starts on the first try, but it always starts on the 2nd"

I thought that was redneck logic.... so me being the analytical guy that I am started testing hypothosis...

put the key to "On" then wait a second (he might not be letting the fuel pump build pressure) Nope. still only starts the 2nd time
Let it crank for longer (he might not be letting it reach an ignition event the first time) Nope, if you let it crank, it just keeps cranking and there's no combustion event
Maybe cycling the key on and off resets some relays... so I switched to on, then off, then on and start.... (Nope, just cranks)

No matter what we did, the damn thing only starts the 2nd time you bump the starter...

Solution... I told him to buy a Chevy.

Hipster Lawrence
02-04-2012, 09:23 PM
I havent seen chryslers fail any more or less than anything else. I have replaced way more fuel pumps in general motors cars than chryslers.

chris_trevisiol
02-05-2012, 12:58 PM
ASD relay disables fuel and spark under certain conditions, get a wiring diagram, remove the ASD relay and jump the high current connection using a fused 10 amp jumper wire. This prevents the ASD system from disabling the ignition coil.

Bad grounds are the Number 1. cause of strange problems.
Check voltage drop from crank sensor ground to (-) battery terminal
check voltage drop from cam sensor ground to (-) battery terminal
Both tests preformed while cranking or engine running
If voltage drop is over .5v at any point, replace ground wiring.

HAVE YOU CHECKED IGNITION TIMING? No. 1 cause of hard starts. -> ADVANCED IGNITION TIMING

tom1977
02-05-2012, 06:39 PM
Many times there are bad connections at the battery, grounds, and fusible links on these jeeps.... Good input from above too!