danl44

My wife recently bought a 1999 Grand Cherokee, 4.0 straight six, automatic tranny. It normally runs and idles well. A tune up was supposed to have been done to it before she bought it. A couple of weeks ago she was pulling out of a parking lot and it bucked a bit and the check engine light came on. The code was P0302 number 2 cylinder misfire. The motor still ran well after that so I cleared the code to see if it would happen again and then I would change the coil packs and spark plugs myself. Now a week later, she was driving on the highway and the motor just quit on her. She was able to pull over and restart the vehicle after she put it in “park”. No “Check Engine” lights came on. So I decided I would drive it around a bit to see if it would happen to me. I was driving down a back road going about 35 mph when I took my foot off the gas and braked slightly for a curve. When I went to accelerate again, I noticed the engine was dead. I coasted to the side of the road, put it in ”park” and tried to restart it. After a few cranks and some gas, it started. The “Check Engine” light was not on. When I got home, I accessed the codes through the ignition switch and it showed the code P0320 on the odometer. I’ve crawled this forum and I’m wondering if I got the P0320 code from the engine dying or from me trying to restart it after it died. I am tempted to replace the crankshaft position sensor with an OEM part but I don’t want to start throwing parts at it. I’ve read a few posts from people who’ve changed that part but still had the same problem. People would come back with “use OEM replacement parts”, but I didn’t see where people said they did and it fixed the problem.

vadergator

the PO320 code is from when you tried to start it back up, & no crank signal was detected by the computer from one of your sensors. usually that would be your CPS (crank position sensor) or your camshaft position sensor / pick-up / relay in the distributor cap ( underneath rotor). your cps can cause the jeep to stall unexpectedly. usually it's when you get a no start situation that you realize it's bad. the cam sensor controls the timing of each cylinder's fuel injector ( your PO302) , and can cause stalling / no start situations as well. if not for the PO302 code, i would tell you to check the TPS or MAP sensors. i feel it's the cam sensor. one misfire can cause an interrupted signal (short) to the computer and cause the jeep to go into limp / shutdown mode. the cam sensor is easier to change than the crank sensor. change it first. then if you still have a no start / stalling issue, change the crank sensor. most people's problems on here usually involve more than one part sometimes. some codes can apply to more than just one sensor. swap the wrong one, you'll be back on here saying it didn't work etc. you probably already checked your connector for a loose wire on that injector. so go for the cam sensor. it's got to be that. come back for more help or to give a successful testimony.

GrandLaredo99

I also own a 99 Jeep Grand Laredo, 4.0 straight six, automatic transmission, that recently had a brand new SKIM module replaced and along with 2 brand new keys. The jeep would shut down after 3 seconds flat after firing up. So I took it straight to the dealer and $625 later, that issue is resolved. However, now the jeeps shuts down on me while I'm driving and the codes I get are p01685 and p0320. I don't understand why I would have p1685 if that is a brand new part. I can understand p0320, by the way, it cranks over well enough, just doesn't fire up. After about 5-10 mins, it will fire up after cranking and I will go on my way, but it will happen randomly again. I've read the forums and have also read a few posts where they have replaced that part and are still having issues with it afterwards. Let me add, that I had the crankshaft position sensor replaced 2 years ago, and at the time it wasn't the issue, rather it had been the SKIM module that needed replacing, which was recently done about 2 weeks ago. What's funny is, the diagnosis did not pick up the error, and this problem had already occurred, the shutting down while driving, before I took the jeep to the dealer to have the SKIM module replaced. The shutting down while driving was actually a new issue that prompted me to take it to the dealer, only they confirmed it was the SKIM module. Any ideas or guidance on where I should begin?