P0340 Solved
- Thread starter Bigfoot-NM
- Start date
Another update. It has been down in the teens the past two nights and the high yesterday was only about 36. I went out this morning after the Jeep was sitting for a couple days. 28 degrees out. Jeep started right up and idled fine.
Thanks for the update. I replaced mine yesterday, it was 11 degrees outside and 25 degrees in my garage this morning, no code appeared upon starting. I will wait for a prolonged cold spell and the car sitting for 2 or 3 days and see how that goes.
Tom
We have a had a cold spell for several days now, still lookin' good!
Hope someone has seen this before:
2006 TJ is throwing the P0340 . Cranks up fine but in the 1st and 2nd gear it seems to stumble. Almost like a loss of power for a second and then picks up. It feels like a jerk (as if the heart missed a beat).
Any suggestions? I have scoured this forum but cannot find these symptoms reported by anyone before.
Thanks!
2006 TJ is throwing the P0340 . Cranks up fine but in the 1st and 2nd gear it seems to stumble. Almost like a loss of power for a second and then picks up. It feels like a jerk (as if the heart missed a beat).
Any suggestions? I have scoured this forum but cannot find these symptoms reported by anyone before.
Thanks!
disconnect your battery and let it sit for a bit. Reconnect it and then drive. If the stumble goes away, it is likely a Jeep computer issue. If this is the case, I would look into wranglerfix.com; this has fixed many TJs that have had that issue. It’s a bit pricey. You can also look into flashing your computer at a Jeep dealership, but a lot of dealerships are phasing the TJ tools to do this out. You will have to shop around. This is much cheaper but the evidence of efficacy is sparse.
If you replaced you camshaft sensor recently, this is also a possibility of cause. There are very few “good” camshaft position sensors that exist anymore for the TJ. When this is changed out, you can have some issues similar to this.
if neither of these do anything, I’d continue to look around For an answer
Thanks @ndaddy
I disconnected the -ve battery terminal. Let it sit for 10 mins. The stumble/miss went away. Check Engine Light went away. Everything works dandy now. But I am terrified to drive it for longer distances, wondering if this issue will re-surface.
The wranglerfix's PCM is about $1k for my jeep.
I did not replace the camshaft sensor.
I disconnected the -ve battery terminal. Let it sit for 10 mins. The stumble/miss went away. Check Engine Light went away. Everything works dandy now. But I am terrified to drive it for longer distances, wondering if this issue will re-surface.
The wranglerfix's PCM is about $1k for my jeep.
I did not replace the camshaft sensor.
@Wranglerfix has high confidence rate; if you search the forums you will discover that. I can also vouch as a customer. It also offers a 1 year warranty and a return/refund in the event it does not fix it. Mark is the owner, he is real chill and will chat with you for hours if you have questions or even if you're just looking for a friend to talk to
.You have to be careful with other companies, but if you do your research you may be able to find a different one that is affordable yet functional. You can also start doing more research into the computer flash but that is getting harder and harder to find a dealer who will do it, along with finding the proven results (which may be a good thing if it fixes the issue and there is no need to come back). I remember a lot of the forums saying that the dealership would look at them like they were crazy when they would ask for the update/flash.
Seems like the computer is your problem with this given context. The jolting will come back; it varies each time. Give mark a call / text and you can explain your issue. He's the expert
@bobcat Give me a call to discuss Operation Mockingbird, Operation Popeye or Jeep computers...I will get you taken care of on all levels. 866-888-7710.
Thanks for this group share. I had the “cold start” issue with my ‘05 TJ unlimited. Picked up the Eschlin 1159 sensor and cured my P0340 code issue immediately.
jeep2fun
Member
DropTopDon
TJ Enthusiast
jeep2fun
Member
Has been a couple of weeks, so I will go home and confirm with pic, so other TJ gurus may chime in. The product was the right one though for a 97 TJ — I am not very technical on which is which crank vs cam.
Good advice on the cold temp start issues, I've been worried since it has been getting down into the upper 40's here. My long underwear is wearing thin. 
Crankshaft is at the back of the engine by the bell housing. The camshaft sensor is where the distributor is on the side of the block so on a 1997 there is just a distributor there. The second link posted by @Haaris Khan in post #33 is the camshaft sensor for the 2004. The 2004 is different from the 2005-6. It's a mess, best to pull yours and match it if you are unsure.
I just attempted a sensor swap today but quit when the lower bolt on the sensor failed to tighten. I'm worried that the threads on the housing are bad. Any experience with this? I got it where it was "tightest" and she still starts but do I risk worsening a situation by taking that bolt out...
Thanks!
Thanks!
The 97 still has a cam sensor, its just inside the distributor. The 2000-2002 (and maybe other years) have no dizzy but a cam sensor that goes in roughly the same place... it's like half of a distributor-- the lower half is the same, but there is no rotor & points & obviously(?) no spark plug wires.
The one OP linked to in the first post sure LOOKS like a crankshaft position sensor. I definitely didn't know the 04 cam sensor was different from the prior years that also had no distributor. Interesting.
2000 cam sensor: