No spark.

krklinegvr4 · #1 04-25-2009, 04:04 PM

Crank, no start.

Fuel pressure 50psi. With key on, fuel pump stays running all the time, never shuts off. Also with key on, the gas gauge reads empty and I put 2 gallons in it. Tank def has fuel in it. Filled up last night and I put 2 gallons in this morning but gas light stays on and needle doesn't move. Normal? Maybe it doesnt read gas level until car is running?

Test ignition, no spark at spark plug. Test spark to distributor, no spark being delivered to distributor. Test for a 12v signal to coil pack and nothing. Put in new crank sensor, still no ignition. Tested new crank sensor and no 5v signal. I am going to test the ignition pick up in a little bit.

Swapped ASD relay with a new one, still no ignition.

Thinking an ECU issue? Going to check all grounding points and maybe replace the ignition pick up in the distributor.

Not a jeep guy at all.. ideas?

krklinegvr4 · #2 04-25-2009, 05:19 PM

Found this...

"The shifter has a switch that Allows the Starter Motor to crank BUT cuts-out the Ignition system so the car cannot start. A sympton is that your Guages will All be dead, even thought your stater turns over.
TEMP SOLUTION: Jiggle the shifter shift it back and forth. Them try the key and check the guages"

But where is the sensor to replace?

This is exactly my case. Gauges are dead, no ignition

Airjer_ · #3 04-25-2009, 05:29 PM

What year?

Grey key or black key?

krklinegvr4 · #4 04-25-2009, 05:33 PM

Quote:

Originally Posted by Airjer_

What year?

Grey key or black key?

98 grand cherokee laredo black key

CLiff notes. Cranks, no spark. Gauges are all dead. FUll battery full tank of gas, all gauges dead with key on and when starting. Gas light is on saying no gas but plenty of gas in fuel rail, 50psi. FUll pump stays on all the time with key in on position. Pump will not shut off until key is out.

Airjer_ · #5 04-25-2009, 05:42 PM

Maybe you have a failed ignition switch?

krklinegvr4 · #6 04-25-2009, 05:45 PM

Quote:

Originally Posted by Airjer_

Maybe you have a failed ignition switch?

Car cranks over fine and car died while driving.

How to test for a failed switch?

Airjer_ · #7 04-25-2009, 05:52 PM

Cam sensor! Should be located on the passenger side of the engine. Should see it from under the vehicle.

Airjer_ · #8 04-25-2009, 05:56 PM

Never mind I was thinking 4.7 liter
what engine?

krklinegvr4 · #9 04-25-2009, 06:09 PM

Quote:

Originally Posted by Airjer_

Never mind I was thinking 4.7 liter
what engine?

Are you just guessing or basing your posts off actual expierences or general knowledge?

Its the inline 6 4.0

I would like to test the part instead of replacing it because "maybe" it might be it. I already played the maybe game, now I am going to test ech part. You know how bad it will be to put in a new ignition switch + programming and still have it not work?

reekor · #10 04-25-2009, 10:53 PM

Crankshaft sensor.

Quote:

Originally Posted by krklinegvr4

Are you just guessing or basing your posts off actual expierences or general knowledge?

Its the inline 6 4.0

I would like to test the part instead of replacing it because "maybe" it might be it. I already played the maybe game, now I am going to test ech part. You know how bad it will be to put in a new ignition switch + programming and still have it not work?

Airjer_ · #11 04-26-2009, 11:02 AM

Quote:

Are you just guessing or basing your posts off actual expierences or general knowledge?

Only 15+ years working on all makes and models

Quote:

I would like to test the part instead of replacing it because "maybe" it might be it. I already played the maybe game, now I am going to test ech part. You know how bad it will be to put in a new ignition switch + programming and still have it not work?

You don't have a lab scope do you? Or a scan tool? You don't have the tools to test so how are you going to test?

Has anybody else chimed in?

Quote:

Originally Posted by reekor

Crankshaft sensor.

Since you already tried that and it didn't work I guess that was less help than the posts I made?

Just trying to give you some direction! If you have a black key than there is no "reprogramming". Only the grey keys need to be programmed not the ignition switches. So if you get a new grey key you will need to have it programmed into the vehicle. You can replace the ignition switches all day long!

Airjer_ · #12 04-26-2009, 11:05 AM

Just to clarify you have power to the coil? you have 9 volts to the pickup coil in the distributor (orange wire)?

nova73noir · #13 04-26-2009, 02:49 PM

Quote:

Originally Posted by Airjer_

Just to clarify you have power to the coil? you have 9 volts to the pickup coil in the distributor (orange wire)?

do you have an anti theft system other than the original if you have one its maybe fail and the only solution its to remove it

krklinegvr4 · #14 04-26-2009, 09:36 PM

Quote:

Originally Posted by Airjer_

Only 15+ years working on all makes and models

You don't have a lab scope do you? Or a scan tool? You don't have the tools to test so how are you going to test?

Has anybody else chimed in?

Since you already tried that and it didn't work I guess that was less help than the posts I made?

Just trying to give you some direction! If you have a black key than there is no "reprogramming". Only the grey keys need to be programmed not the ignition switches. So if you get a new grey key you will need to have it programmed into the vehicle. You can replace the ignition switches all day long!

Yes I have a scan tool. Doesn't connect. You said you have been a mechanic for 15+ years but how long have you been reading for?

Quote:

Originally Posted by krklinegvr4

Crank, no start.

Fuel pressure 50psi. With key on, fuel pump stays running all the time, never shuts off. Also with key on, the gas gauge reads empty and I put 2 gallons in it. Tank def has fuel in it. Filled up last night and I put 2 gallons in this morning but gas light stays on and needle doesn't move. Normal? Maybe it doesnt read gas level until car is running?

Test ignition, no spark at spark plug. Test spark to distributor, no spark being delivered to distributor. Test for a 12v signal to coil pack and nothing. Put in new crank sensor, still no ignition. Tested new crank sensor and no 5v signal. I am going to test the ignition pick up in a little bit.

Swapped ASD relay with a new one, still no ignition.

Regardless of ignition issue, I was able to get the computer back and look on mitchels for a wiring schematic. I found a break in the wire running to the fuse box under the hood (20amp fuse) I replaced wire and gauges came back to life and then ignition came back to life. That wire goes to the gauges, 4wd indicator light, & ignition switch.

Problem solved. Ended up being a broken wire between ignition switch and fuse box.

reekor · #15 04-28-2009, 10:49 AM

Kind of a dink, no?

Quote:

Originally Posted by Airjer_

Only 15+ years working on all makes and models

You don't have a lab scope do you? Or a scan tool? You don't have the tools to test so how are you going to test?

Has anybody else chimed in?

Since you already tried that and it didn't work I guess that was less help than the posts I made?

Just trying to give you some direction! If you have a black key than there is no "reprogramming". Only the grey keys need to be programmed not the ignition switches. So if you get a new grey key you will need to have it programmed into the vehicle. You can replace the ignition switches all day long!

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