EHarris

I'm trying to solve my extended crank time. One of the easy fixes especially for my 2008 year is to replace the Cam Position Sensor at least I thought. I read a few posts on here that it solved the extended crank so I ordered it from Rock Auto a few weeks back. I went to put it in today and re-read the Technical Service Bulletin.

http://project-jk.com/images/tsb/TSB_08-001-08-REVA.pdf

I have a 2008 Automatic trans 3.8 and the MDH is 020213

According to the TSB it says that I should not replace the Cam Position Sensor but I should reprogram the PCM. I have already replaced the Cam Position Sensor earlier this afternoon and after a few no cranks it started right up and appears to be running fine.

I used part number MOPAR 5149078AD from rock auto but the TSB says 05149078AC. Did I just replace it with the wrong sensor? I did notice that the old sensor did not have the piece of cardboard at the end and the new sensor does. I listened to the TSB and left the piece of cardboard at the end on and installed it.

Anyone know what's going on here? I'll report back if it fixed my extended start time but I hope I don't get stranded now because of a different part number or something weird like that. I am replacing parts at 150k to help improve reliability since I use my vehicle in areas where no help is available nor are any parts (Baja).

Should I also replace the Crank Position Sensor at this point too? 151k on the vehicle now. Any other sensor replacement? ERG Valve? O2 sensors? PCV valve?

I have the lifetime powetrain warranty so I think its time to get a new water pump possibly too.

EHarris

Update. Just went to start the JK and it won't start. Tried it about 10 times and it finally kicked over. It's as if it doesn't know where the position is on the cam sensor.

Before this I would have said it solved my issue. I didn't get the extended start any longer.

But now it seems as if it needs a reprogram or wrong part.

EHarris

Stuck again today after work.


It eventually kicks over but this is very strange. Anyone replace the cam position sensor?

This seeks more like a possible power issue or battery ground maybe? But all major grounds cleaned recently, all checked tight this evening.

EHarris

Stuck again this morning.

I'm going to get the battery load tested and I'll also pull the starter and see if anything is wrong there.

Any advice from anyone on this? Hopefully soon lol I'm scratching my head here.

resharp001

Wish I could be of some help Eddie, but this one isn't something I've had to deal with. Free bump to the top though. Would think maybe Ronjenx might have a thought, or Karlsjk10, Rednroll, or MrT.

Mr.T

Looks like the cam sensor is correct -- The leading zero in the TSB can be dropped and the AD suffix means it's one revision higher than AC. That's a 2008 TSB, so the PCM was likely updated at the dealer sometime in the past, probably a revision well beyond the date of that TSB.

Have you had the P0340 / P0344 codes mentioned in the TSB?

Edit: just watched the video and it might be the battery itself, or terminals, ground, etc. -- essentially voltage dropping too low (as in < 9 volts, ) as it energizes the starter. It looked like some of the dash lamps flash off when they normally don't. Measuring voltages at the battery posts, terms, at the starter motor are some of the first places I'd start.

EHarris

Thank you so much for the TSB info. A little more piece of mind. I have a portable jump start battery pack. This afternoon it started on the first turn with the battery pack. I then immediately drove it to auto parts store to have them load test it. They said it passed load test.

At battery terminal the voltage was 12.6 without it running and 14.15 with it running and accessories on.

Tomorrow morning if it doesn't start which I doubt it will I can check the battery again and see what the reading is in the no start condition. I'm assuming it might be below the 12.6 mark.

With 151k should I be considering changing out the alternator anyway even though it appears this is the battery.

It's a die hard battery sears agm gold and I got it in March. It's only 8 months old and it seems like it could be shot.

I guess I won't be buying that brand anymore. Especially since sears won't be around to warranty it. Interstate at Costco could be my next stop.

Mr.T

Suggest checking the voltage right at the batt posts, both before cranking and during the first attempt tomorrow. It may actually start, but the readings may tell you which way to proceed.

If the voltage is less than ~12.5 before cranking, it may have discharged during the night -- could be an internal battery issue or an external draw. If the voltage dips less than ~10.5 (figuring it's not too cold in SoCal, colder temps lower the voltage) during the cranking attempt there's about a 98.79% chance it's the battery. If the battery is actually good, what makes the voltage go too low are things that draw excess current -- like a seized engine or a bad starter motor.

The beauty of this test is that with low voltage at the battery posts during cranking there is no reason to suspect bad connections/grounds because it's damn near impossible to have excessive current with bad connections. So as long as the battery has normal full charge voltage to start with, low cranking voltage measured at the battery posts has a binary result: Either the battery is bad (or undersized) and can't supply the load, or there is excessive amperage (bad starter, seized engine, etc.)

Mr.T

Also, might want to read this thread. Spendy, but it might be cheap insurance in Baja. Technical Review: Odyssey 34-PC1500T Battery

EHarris

So this morning before I tried to start it, 12.27v at the battery terminal. It wasn't as cold as the past 3 nights at all and i did drive it to get a burrito around 8pm so it may have been slightly more charged. It did start on first try but it was a weak start.

Maybe you guys can check over my game plan:

1. Trickle charge the battery for a few nights to see if it comes back to life. It will be replaced soon with another AGM battery. Just have not decided if I'm gonna pull the trigger on an Yellow top or generic AGM.

2. I have an extra mopar starter that was the original. It has 60k. I had a no start issue that was solved by the extra ground wire to the alternator bracket. I thought it was the starter when I was new with all of this Jeep stuff. Could I maybe have the extra mopar starter rebuilt locally and then I can install it considering it brand new? Current starter has almost 100k.

3. Replace alternator? Maybe my batteries are going bad (2 mopar batteries and 2 agm's in 151k) because the alternator is starting to go also. It's the original with 151k on it now. Seems like a good time to replace it. I was considering a mean green starter since it's 220 amps but I have read some bad things about them. Cost, reliability and it sounds like with all the extra amps you must do a big 3 wire upgrade for the mean green. My other options would be mopar alternator or a remanufactured mopar alternator. A new mopar is same price as mean green. A reman from rock auto looks to be around $250.
Any input would be greatly appreciated on alternators.

4. From what I have read the coil pack doesn't break down. It would just die. Should I consider doing the coil pack also just for the F of it? Or is that just a waste of $70

I plan on driving this for at least another 50-75k and I have the lifetime powertrain warranty still in effect.