-   TJ Wrangler Technical Forum (
-   -   98 jeep wrangler cranks but wont start, no spark (

wade1465 06-25-2012 07:18 PM

98 jeep wrangler cranks but wont start, no spark
new crankshaft position sensor, getting power to the distributor, fuses look good, test light shows im not getting power in the wire to the ignition coil? any ideas cause im stumped

shatteredsoul 06-25-2012 07:40 PM

Check your cam shaft/ pick up sensor inside the distributor, IIRC it can cause a no spark condition as described at the coil.

wade1465 06-25-2012 07:56 PM

I replaced the distributor pickup as well

n5xl 06-25-2012 08:45 PM

Battery voltage is fed to the coil from the ASD relay (auto shutdown relay) via key on and commands from the PCM during a starting sequence. Many of the tests look for voltage but the PCM only commands the ASD on for 3 seconds then shuts it down, so you have to determine ASD functionality within three seconds (the fuel pump is controlled by the PCM the same way so use the sound of the fuel pump running to know when to expect voltage and when not to.

I looked at the wiring diagrams and start logic and put this together...I hope I did it right :D

1. Verify you are probing the correct wire (orange wire) at the coil for battery voltage during a cranking sequence. If not seeing 12 volts at the coil (referenced against the battery negative terminal) during a cranking sequence, continue to step #2. If you are seeing battery voltage, probe the grey wire at the coil for ground during a cranking event. If you see ground pulses, suspect the coil. If you dont see ground pulses, suspect the crank or cam sensors
2. Check Fuse 11 in the PDC. If good continue to step 3, if burnt, replace fuse.
3. Unplug the ASD relay in the PDC and verify the orange wire at the coil and ASD relay socket cavity 8 is connected and showing low to no resistance. If good continue, if not good, check fuse 21
4. Probe the ASD relay socket cavity 4 for battery voltage with the key on. If good continue, if not check Fuse 11 in the PDC.
5. Probe ASD relay socket cavity 2 for 12 volts with the key on (there may be a 3 second window to see this, timed with the sound of the fuel pump running). If good continue, if not good check Fuse 19
6. Verify ASD relay socket cavity 6 is at battery ground potential during a cranking sequence (there may be a 3 second window to see this, timed with the sound of the fuel pump running). If good, suspect the ASD relay, if not, suspect the crankshaft position sensor or camshaft position sensor.

NL-Blackbear 06-26-2012 12:16 AM

had same issue, turned out to be a croded wire in the fuse box. fix was tedious but easy, checked all wires in cluster untill i found it, cut it out, replaced it

wade1465 06-26-2012 07:41 PM

alright i did all of that figured out the 3rd plug from left to right attatched to my computer has a bad connection and wiggling it around gets power to the ignition coil and all just fine now. but now when i went to crank it gas built up real bad in the spark plugs and started pouring out of the throttle body???? what would be causeing that?

The time now is 02:02 AM.

Powered by vBulletin Version 3.8.8
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.

User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.