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Jessica4Bama

Jessica4Bama

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So the other day at work I went to crank my Jeep to head to the postal. It wouldn't crank. The engine would turn over, but it wouldn't start (hopefully I'm explaining that right). Anyway, my dad checked a part to make sure it was getting fuel to it. Not sure what he tested. I ran a code check on the Jeep, and it came up P0340. Well it sounded easy enough to replace the cam sensor so my cousin ordered one from O'reilly. He put it in yesterday, and it cranked up fine. He cleared the error code, and all was well. I went to get lunch, and it didn't feel like it did before but I figured it was my imagination. Fast forward four hours till time to go home. It won't crank again. I had to call my mom to come get me. Felt like middle school all over again, hehe.

I did more research, and I learned I should put a factory Mopar sensor back in because Jeep's are picky with that sort of thing. I ordered a new one so I asked my cousin to take out the one we had replaced and put back in the old until the new one arrived. I finally got it to crank using the old sensor so I decided to see if I could make it home without stalling. I did thankfully, but it has me concerned something else is going on. No error code came up when we put back in the old sensor.

Any advice what else we could look for or replace before having to have it taken to a mechanic? I want to avoid that if possible. Could it be something with the battery or maybe the fuel filter?

Surely my my tide brothers and sisters have some experience with vehicle failures. :)

My online research isn't netting me much results, unfortunately.
 
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AUDub

AUDub

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Give me ambiguity or give me something else.
Times like this I wish I knew cars, but I do know electrical. Looking up code shows that the problem could be anywhere on the cam position sensor circuit. Could be the wiring, the PCM or the sensor itself. Since you replaced the sensor I'd go ahead and rule that out. Visually inspect the wiring for frayed or damaged cable.

I'll hunt and see if I can find a diagram to troubleshoot the PCM with a multimeter.
 
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Jessica4Bama

Jessica4Bama

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Nov 7, 2009
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AUDub said:
Times like this I wish I knew cars, but I do know electrical. Looking up code shows that the problem could be anywhere on the cam position sensor circuit. Could be the wiring, the PCM or the sensor itself. Since you replaced the sensor I'd go ahead and rule that out. Visually inspect the wiring for frayed or damaged cable.

I'll hunt and see if I can find a diagram to troubleshoot the PCM with a multimeter.
Click to expand...
Thank you.

The wires connected to the sensor looked fine to me when I inspected them today. I'm not sure where the cable leads so I didn't check that far back.
 
TIDE-HSV

TIDE-HSV

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I was thinking coil even before I read Brad's link. It the wires show continuity and then, if you give the coil a good whack and it fixes the problem temporarily or kills it permanently, then I'd get a new coil pack...
 
bamacon

bamacon

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Apr 11, 2008
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NationalTitles15 said:
Trade Jeep in....problem solved. No, seriously.

But if that isn't an option then I haven't a clue. Jeep are notoriously ornery beasts. My advice is to take it to someone well versed in Jeeps.
Click to expand...
This. I loved my Jeep but hated it because it was ridiculous working on it ALLLLLL the time. The new ones are much improved but alas way out of my price range or lifestyle compatibility.


Sent from my iPhone using Tapatalk
 
cbi1972

cbi1972

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Nov 8, 2005
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My fiancee loved her Jeep but she got sick of the problems, particularly the electrical.
She got a new Ford Escape and couldn't be happier with it.
 
danb

danb

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Dec 4, 2011
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Depends on year, engine size, etc... A cam sensor code can falsely set when continually cranking over the engine.

I've been out of the profession for several years, so take this with a grain of salt..... On the older jeeps, if you had an intermittent no start problem, with fuel pressure present, most of the time It wound up being the CRANK sensor (It creates the RPM signal to the computer, which in turn, pulses the injectors and fires the ignition)

But without being there to check it, it's just another SWAG..(sophisticated wild a.. guess!!)
 
RedStar

RedStar

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Jessica4Bama said:
So the other day at work I went to crank my Jeep to head to the postal. It wouldn't crank. The engine would turn over, but it wouldn't start (hopefully I'm explaining that right). Anyway, my dad checked a part to make sure it was getting fuel to it. Not sure what he tested. I ran a code check on the Jeep, and it came up P0340. Well it sounded easy enough to replace the cam sensor so my cousin ordered one from O'reilly. He put it in yesterday, and it cranked up fine. He cleared the error code, and all was well. I went to get lunch, and it didn't feel like it did before but I figured it was my imagination. Fast forward four hours till time to go home. It won't crank again. I had to call my mom to come get me. Felt like middle school all over again, hehe.

I did more research, and I learned I should put a factory Mopar sensor back in because Jeep's are picky with that sort of thing. I ordered a new one so I asked my cousin to take out the one we had replaced and put back in the old until the new one arrived. I finally got it to crank using the old sensor so I decided to see if I could make it home without stalling. I did thankfully, but it has me concerned something else is going on. No error code came up when we put back in the old sensor.

Any advice what else we could look for or replace before having to have it taken to a mechanic? I want to avoid that if possible. Could it be something with the battery or maybe the fuel filter?

Surely my my tide brothers and sisters have some experience with vehicle failures. :)

My online research isn't netting me much results, unfortunately.
Click to expand...
How is your idle? What year/model/engine type?
 
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Jessica4Bama

Jessica4Bama

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RedStar said:
How is your idle? What year/model/engine type?
Click to expand...
Yesterday morning before we put the old one back in, it wouldn't idle. It would die as soon as you let off the gas. We put the old one back in, and it took a minute to get it cranked, but it finally did and it finally idled. It idled fine for about 10 minutes before I tried to make it home with it. I finally did.

It is an 02 Wrangler 4.0L 6 cycl.
 
RedStar

RedStar

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Jessica4Bama said:
Yesterday morning before we put the old one back in, it wouldn't idle. It would die as soon as you let off the gas. We put the old one back in, and it took a minute to get it cranked, but it finally did and it finally idled. It idled fine for about 10 minutes before I tried to make it home with it. I finally did.

It is an 02 Wrangler 4.0L 6 cycl.
Click to expand...
While I don't think this is your main problem (It sounds like it might be the combination of a couple of things going bad simultaneously) there's a good chance the Idle Air Control Valve is dirty. Especially with it being an '02. In my 2000 I had similar problems. It would crank and sometimes die unless I gave it enough gas. I took off & cleaned the throttle body and the IAC, cleared the code & haven't had a problem since, my idle also greatly improved, no shaking.

Some people have luck cleaning the valve, some say once it's that old you need to replace it anyway. But your thinking on Mopar products is right, never go with another brand. Jeeps are picky when it comes to their parts.

I'd take off the throttle body & remove the IAC valve, and clean both. That wont cost you anything, so even if that's not the source of the problem, it probably needs it anyway. It's pretty easy too. I'm sure there's a YouTube video showing how to do it.
 
Jessica4Bama

Jessica4Bama

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Thank you, RedStar. My dad seems to think it's something to do with the fuel filter, but that looks like a pain in the rear to remove and pricey.
 
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Jessica4Bama

Jessica4Bama

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Nov 7, 2009
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Sorry to keep bumping this thread, but I just went out to see if it would start. It cranked like nothing was ever wrong with it. Would it be okay to drive? I sure don't want it to strand me anywhere. I'm still going to replace the sensor just in case.
 
Sgtsmokdu

Sgtsmokdu

BamaNation Citizen
Oct 10, 2011
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My wife had a 04 (I think) Chrysler Crossfire. A lot of the time it would have the same symptoms as your jeep. I replaced just about every sensor on it. The day that it died on an on ramp was the same day that it was traded in!

To be fair to Chrysler, it did Mercedes Benz motor and transmission.

Good luck!

Sent from my LG-VS985 using Tapatalk
 
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