Odd no start prob 96 Cherokee - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Cherokee & Comanche Forums > XJ Cherokee Technical Forum > Odd no start prob 96 Cherokee

15 x 8 Black D-Window Steel Wheels Set of 4Advance Adapters SYE KitsRIGID LED Light Blowout Sale - All Sizes, All Series, all

Reply
Unread 06-30-2013, 07:00 PM   #1
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Odd no start prob 96 Cherokee

Hey all, I am having an odd no start condition in my right hand drive 96 Cherokee. When I bought it a few weeks ago the seller told me of a few issues, one being a check valve in the fuel pump/tank that allows fuel to drain back to the tank when it sits. No biggie just turn on the key and let it prime. Which worked the first time I drove it away. Then it started to become a hassle using it for mail delivery all the time and waiting 15-20 minutes every morning before it finally fires. I've searched and searched and haven't found much to pinpoint it. Now lemme explain the problem. First off I get the NSS code, P1899, but to my knowledge that shouldn't allow it to crank, and not a crank and no start. I can crank it no matter where the shifter is. The weird problem I am noticing is when I first turn the key on to prime the fuel rail I should get all the warning lights to come on, key on engine off. The only light that comes on is the brake warning light. After a while I notice the Gen/Check Engine lights start to flicker then eventually coming on solid after turning the key on and off a few times, 25-30. Once those lights come on is when she'll start. If those lights don't come on while priming fuel pressure then I can crank all day and nothing. My question, is the Crank position sensor some how related to these lights and getting it to fire? Is the NSS related to this? Once I notice the lights coming on a few times of switching the key it will start every time. Sometimes it takes longer than others but it starts. After that I never have a problem all day. Even if I have to get out for gas, or get out at a condo and shut the engine off I turn the key back to the on position and it fires up every time. Only cold starts are like this, which throws my thinking off of most electrical problems happening when the part gets hot. Maybe there's some kind of short? Bad wiring? I've looked it over minimally for now since it sits at the office I work at and I don't have it at home to really get into it right now. I've checked fuses, relays, wiring harnesses, and they all "look" okay, but haven't removed anything yet to clean and thoroughly inspect. Anyone have any suggestions?

RJacks258 is offline   Reply With Quote
Unread 07-01-2013, 07:43 AM   #2
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
All the members on this forum and no one has the slightest suggestion?
RJacks258 is offline   Reply With Quote
Unread 07-01-2013, 08:05 AM   #3
Pats94
Registered User
2001 XJ Cherokee 
 
Join Date: Mar 2012
Location: Des Moines, Ia
Posts: 421
The first thing I would do is replace the CPS and clean NSS. I don't usually just throw fixes around but these are good things to do especially if the history is a little foggy. Then I'd replace anything wrong with fuel delivery.
Nothing worse then needing to go and screwing around waiting for the fuel system to prime.
__________________
If its stock it sucks and if it scares the hell outta ya its just about right!
Pats94 is offline   Reply With Quote
Unread 07-01-2013, 08:16 AM   #4
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Thanks for the reply. Although I do plan on replacing the parts that are causing issues with the fuel delivery, I want to pin point his particular issue. I'm not typically a parts replacer just to narrow stuff down. The CPS does sound like it could be the prob although I've not read anywhere any relation to why the warning lights don't come on until after a few turns of the key. And then I get it to come to life.
RJacks258 is offline   Reply With Quote
Unread 07-01-2013, 08:57 AM   #5
Pats94
Registered User
2001 XJ Cherokee 
 
Join Date: Mar 2012
Location: Des Moines, Ia
Posts: 421
Quote:
Originally Posted by RJacks258 View Post
Thanks for the reply. Although I do plan on replacing the parts that are causing issues with the fuel delivery, I want to pin point his particular issue. I'm not typically a parts replacer just to narrow stuff down. The CPS does sound like it could be the prob although I've not read anywhere any relation to why the warning lights don't come on until after a few turns of the key. And then I get it to come to life.
Take for what its worth but make sure you get a genuine jeep cps.
__________________
If its stock it sucks and if it scares the hell outta ya its just about right!
Pats94 is offline   Reply With Quote
Unread 07-09-2013, 06:13 PM   #6
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Replaced CPS. Cleaned and lubed NSS. Replaced Vehicle speed sensor for another reason. Checked grounds, PCM connections, ignition switch connections, and some other relays switches sensors etc. Still doing the same.
RJacks258 is offline   Reply With Quote
Unread 07-10-2013, 11:51 AM   #7
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Yet another update, maybe someone will chime in that has a direction towards a solution:

Replaced ignition switch, cleaned all grounds. Look for shorted, corroded, dirty, non desirable etc. wires or connectors. Found one under the dash, but after a while of trying to start it, it fired and said connection was still disconnected. So obviously not related to my problem.
Found a bad rear temp sensor connector last night, fixed and securely attached it.
One odd thing I noticed today was with the fuel pump and it's relation to this problem. When you first try to start it and turn the key on, the pump comes on and runs but stays running. Now when I turn the key and the dash lights come on finally, the pump will come on and shut back off after 3-5 seconds like it's supposed to. Now what is controlling the fuel pump directly allowing it to run forever when the dash lights don't come on as opposed to it shutting off like it's supposed to when they do finally come on?
RJacks258 is offline   Reply With Quote
Unread 07-10-2013, 07:06 PM   #8
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Is this problem too technical for the forum?
RJacks258 is offline   Reply With Quote
Unread 07-10-2013, 07:19 PM   #9
XJaySC
Registered User
1997 XJ Cherokee 
 
Join Date: Feb 2009
Location: Charleston
Posts: 228
Quote:
Originally Posted by RJacks258 View Post
Is this problem too technical for the forum?
We could all throw guesses your way if you'd like but some of the more technical guys are not in here daily to wade through the "what lift" type questions. Give it time and someone should chime in.


To answer your question "What would cause the fuel pump to continuously run?" (with my limited knowledge) I'd say bad pump or bad PCM. If all wires check good communication is usually bad.
XJaySC is online now   Reply With Quote
Unread 07-11-2013, 05:30 AM   #10
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
I've been thinking PCM, can't be a bad pump because it works as normal once the CEL/GEN lights come on with the key in the on position. It's only when they don't come on does it stay running.
RJacks258 is offline   Reply With Quote
Unread 07-11-2013, 09:49 AM   #11
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Odd thing is while running, if I unplug the NSS harness it idles up then back down to normal. When I plug it back in, it drops then back up.
RJacks258 is offline   Reply With Quote
Unread 07-11-2013, 01:41 PM   #12
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Checked voltage going to cam sensor.

When dash lights come on I've got 5v. But sometimes when they are on I don't always get any voltage. Definitely don't get any voltage when the dash lights don't come on.

Disconnected crank sensor while doing this to check it and same results with voltage going to the crank sensor.

All in all at least it's not the new crank sensor I just installed.
RJacks258 is offline   Reply With Quote
Unread 07-12-2013, 01:44 PM   #13
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
looking at the wiring diagram volt supply for both the cam and crank sensor come from the same pin from the PCM. Being that when I don't see those dash lights I get zero voltage to both sensors, wouldn't that point to my PCM? I've done some procedures today but the way it's been acting today everything has worked this afternoon. This morning I got up a half hour early to get it started and barely ever got a flicker from the CEL/GEN lights. So I never tried starting except for the crank just to see. I had to call in to work, but ended up going in to help but drove my daily driver. The Cherokee is just for mail delivery and I usually leave it at the post office. Came home at around 10:45 and messed with it and same thing as this morn, nothing for an hour. Then the lights started coming on and I got it fired up and drove it for 20 minutes. I then took about an hour break and used my other truck to go and came back and the lights came on and it fired every try for the last almost 3 hours. The dash lights came on every time and so did it fire. I've let it sit for 5 to 45 minutes and it worked every time.
RJacks258 is offline   Reply With Quote
Unread 07-16-2013, 02:07 PM   #14
RJacks258
Registered User
 
Join Date: Jul 2011
Location: Punta Gorda, FL
Posts: 27
Ended up being the PCM. Thanks to all who contributed any USEFUL info.
RJacks258 is offline   Reply With Quote




Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.