No spark!!! - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > YJ Jeep Wrangler Forum > YJ Tech Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 05-26-2009, 11:04 AM   #1
Newb
 
Join Date: May 2009
Posts: 2
No spark!!!

Hi all, I am a jeep newbie and bought a 94 YJ 2.5 with 86,000 miles on it and have loved it since day one... I have owned it since January 17th and about a month ago the problems started, while driving to work the engine started cutting out and bogging down. I found out that there was a recall on the sending unit gasket that can allow water into the tank. I assumed thats what it was, dumped in a bottle of Heet and went on my way (Got the gasket fixed that same weekend). Everything worked ok for about 3 more weeks then it started up again, this time way worse. At this point I determined it was the fuel pump was going out, so I purchased a new one, dropped the tank and installed it. Turns out that wasnt the problem, I hooked up a fuel pressure gauge up and started the jeep, it held pressure fine for about 2 minutes then dropped rather quickly and held steady at 10lbs which caused the jeep to stutter then stall out. I tested voltage at the pump to see if that was where the problem was, turns out it was staying steady at around 13 volts even when the pressure started dropping up until it stalled. I got tired of dropping the tank so I cut an access panel in the rear of the tub for easy access. I hooked up a portable jump start battery pack to the fuel pump and the jeep ran fine for 30 plus minutes while not connected to anything on the jeep other than the fuel lines, so that pointed me to the fact I had a short somewhere. Well when this was all said and done I hooked all the wires back up and now the engine wont even turn over, I am getting no sparks at the plugs! Headlights, horn all the accessories work just fine, I have checked all the relays under the hood and traced as much wire as I can see and they all seem to be ok. Both myself and my father inlaw are stumped, my next move is to buy a new ECU when we pulled it out to check wiring and connections, we noticed quite a few heat cracks in the silicon protection layer. Anybody got any suggestions on what I could do before I drop it off at the old mechanic shop? Thanks for you help.

Asains is offline   Quote Quick Reply
Old 05-26-2009, 12:59 PM   #2
kik
Jeeper
 
kik's Avatar
 
Join Date: Dec 2008
Posts: 4,442
Images: 1
Check under the coolant expansion tank area to see if you have an Ignition Control Module (some older mechanics call it a spark box) it's usually held on with 3 10mm bolts and has a plug in adapter. It will cost about 100-140 in most parts stores. The reason I say check because I'm not 100% sure on a 94 with a 2.5. If it's there, this is probably your problem.

kik is online now   Quote Quick Reply
Old 05-26-2009, 05:08 PM   #3
Jeeper
 
Join Date: Apr 2009
Posts: 538
sounds to me like a ground problem. you had 12v at pump but still died but ran portable power and ran fine. check your grounds.
dooder is offline   Quote Quick Reply
Old 05-26-2009, 06:10 PM   #4
Jeeper
 
scrambler1's Avatar
 
Join Date: Jan 2008
Location: vermont
Posts: 486
There is no control box that is for the carbed units.0



Have you checked for ECM codes,this where I would try first to make sure that your computer is communicating with the ignition system: Good luck

Put the key in the ignition and turn the key to run (not start), then off, then run, then off, then run (that's 3 runs and 2 offs). Leave the key in the run position. The check engine light will turn on for a few seconds, then turn off, then (sometimes after 20-30 seconds) start flashing. The flashes are counting out 2-digit trouble codes. Fast flashes count up each digit, with a longer pause between digits. 55 indicates the end of all codes.


Code Description
11* No crank reference signal detected during engine cranking.
12* Direct battery input to PCM was disconnected within the last 50 key-on cycles.
13** No difference recognized between the engine MAP reading and the barometric (atmosphereic) pressure reading at start-up
14** MAP sensor input below minimum acceptable voltage.
or
MAP sensor input above maximum acceptable voltage.
15** No vehicle distance (speed) sensor signal detected during road load conditions.
17* Engine coolant temperature remains below normal operating temperatures during vehicle travel (thermostat).
21** Neither rich nor lean condition detected from the oxygen sensor input.
or
Oxygen sensor input voltage maintained above the normal operating range.
22** Engine coolant temperature sensor input above maximum acceptable voltage.
or
Engine coolant temperature sensor input below minimum acceptable voltage.
23** Intake manifold air temperature sensor input above maximum acceptable voltage.
or
Intake manifold air temperature sensor input below minimum acceptable voltage.
24** Throttle position sensor input above maximum acceptable voltage.
or
Throttle position sensor input below minimum acceptable voltage.
25** A shorted condition detected in one or more of the idle air control motor circuits.
27* Injector #1 output driver does not respond properly to the control signal.
or
Injector #2 output driver does not respond properly to the control signal.
or
Injector #3 output driver does not respond properly to the control signal.
or
Injector #4 output driver does not respond properly to the control signal.
or
Injector #5 output driver does not respond properly to the control signal.
or
Injector #6 output driver does not respond properly to the control signal.
33* An open or shorted condition detected in the A/C clutch relay circuit.
34* An open or shorted condition detected in the speed control vacuum or vent solenoid circuits.
or
Speed control switch input below the minimum acceptable voltage.
or
Speed control switch input above the maximum acceptable voltage.

35* An open or shorted condition detected in the radiator fan relay circuit.
41* An open or shorted condition detected in the generator field control circuit.
42* An open or shorted condition detected in the auto shutdown relay circuit.
44* An open or shorted condition exists in the engine coolant temperature sensor circuit or a problem exists in the PCM's battery temperature voltage circuit.
46** Battery voltage sense input above target charging voltage during engine operation.
47** Battery voltage sense input below target charging voltage during engine operation. Also, no significant change detected in battery voltage during active test of generator output.
51** Oxygen sensor signal input indicates lean air/fuel ratio condition during engine operation.
52** Oxygen sensor signal input indicates rich air/fuel ratio condition during engine operation.
53* PCM internal fault condition detected.
54* No fuel sync (camshaft signal) detected during engine cranking.
55* Completion of diagnostic trouble code display on the malfunction indicator lamp (check engine lamp).
62* Unsuccessful attempt to update SRI (service reminder indicator) miles in the PCM EEPROM.
63* Unsuccessful attempt to write to an EEPROM location by the PCM.

* - Check engine lamp will not illuminate at all times if this code was recorded. Cycle ignition key as described and observe code flashed by check engine lamp.

** - Check engine lamp will illuminate during engine operation if this code was recorded.
__________________
__________________
94' wrangler 4 cyl. 5 speed D30/8.8 ARB
82' scrambler 350 TBI/700r4 D30/Currie 9"
07' JK sahara
Whats the deal with the facebook crap?? ->->->->
Grown men should NOT be on Facebook.
scrambler1 is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
2.5l Spark knock Boulderv7 TJ Tech Forum 42 08-19-2009 07:01 AM
Spark Plug HELL Willbanks TJ Tech Forum 44 04-18-2009 11:51 PM
Spark plug questions 2002TJX TJ Tech Forum 13 01-25-2008 06:03 PM
No Fuel No Spark.... Automatic Shutoff??? Raymond85 YJ Tech Forum 2 10-13-2007 01:26 PM
No spark solrac2182 TJ General Discussion Forum 4 09-04-2007 07:20 PM



» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 03:06 PM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC