Keep getting P0340, it turns over but doesn't start. Replaced sensor but nothing, it just turns over but doesn't fire and keep getting P0340. Reset the pcm a few times, left off the battery for few hours at a time. Anyone? Maybe I got a bad replacement sensor..?
P0340, changed sensor but still wont start
djdanrt
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Reset the cpu and replaced the camshaft position sensor with yet another new one and it still turns over but wont fire and spits out P0340. I'm thinking pcm? Thoughts? I don't thinks its mechanical because this happened a week ago and I let it sit a few hours and all was good. If was mechanical it wouldn't be so flaky it would either be broke or not.
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Im ordering a PCM for it(cheap), the 02 jeep tcm might have fried my pcm as its not meant for a 2000.
Saw this on a jeep forum. Perhaps the camshaft target wheel is worn/damaged..? Might explain it being intermittent.
A rationality error has been detected for loss of camshaft position sensor (no fuel sync). WJ 1999 &' 2000: Check the camshaft target wheel (located on the right side camshaft sprocket) for damage or excessive runout. The runout is very critical for proper camshaft signal input to the JTEC. The lateral runout on the target wheel should not exceed 0.012 inch.
Saw this on a jeep forum. Perhaps the camshaft target wheel is worn/damaged..? Might explain it being intermittent.
A rationality error has been detected for loss of camshaft position sensor (no fuel sync). WJ 1999 &' 2000: Check the camshaft target wheel (located on the right side camshaft sprocket) for damage or excessive runout. The runout is very critical for proper camshaft signal input to the JTEC. The lateral runout on the target wheel should not exceed 0.012 inch.
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If the crankshaft woodruff key is broke when you start it wont that make a lot of racket? The pistons would be hitting valves as the crank is turning but the cams aren't, right? Mine turns over without making any bad mechanical sound.
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No, not if they key is not broken yet.... My key was about to break but was actually bent enough for it to throw off the timing.
SPEED SAFE, NICK
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If it is the woodruff key does the crank have to come out? Can I make that fix for it in place? If not I might as well just get it completely rebuilt.
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It would be a tight place to work in. My crank was modified when the engine was built... so I'm not too sure if it can be done in the truck. I would think it could be though.
You could just replace the key with a new one, I know you can do that with the engine still in the truck. When this happend to me thats how they fixed it.
Just make sure the harmonic balancer bolts/torques up SNUG to the sprocket when installed when your done.
NICK
You could just replace the key with a new one, I know you can do that with the engine still in the truck. When this happend to me thats how they fixed it.
Just make sure the harmonic balancer bolts/torques up SNUG to the sprocket when installed when your done.
NICK
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I hope you also put your PCM in the other vehicle to confirm it is good.
Pop out the cam sensor again and see if the target wheel is turning while the engine is cranking.
Then I suppose make the call to pull off the valve cover / timing cover.
Regards,
Kevin
Pop out the cam sensor again and see if the target wheel is turning while the engine is cranking.
Then I suppose make the call to pull off the valve cover / timing cover.
Regards,
Kevin
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I think changing the pcm out should rule out the pcm. The odds of me picking up a pcm thats bad with the same exact problem is unlikely. Also you cant see the cam sensor wheel as it on the underside of the engine.
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I should have been more specific, I was in a bit of a rush when I typed. i did not mean to suggest anything bad at all.
Putting the PCM from the other vehicle is a test but it is not a complete test.
If there was a wiring fault that was causing the code, the new PCM could behave like the original one.
Now if the original PCM had (a) caused the wiring fault OR (b) was damaged by the wiring fault, then you still cannot determine this
so...
FIRST, put the PCM from the vehicle that will not start into the vehicle that is working fine. If it starts and runs fine, THEN you can start to rule out the PCM. Doing this does also lessen the risk of being without either vehicle if there was a wiring problem that cooked the first PCM.
With respect to the cam sensor..... stick your finger in the hole and manually turn the crankshaft. If you can not feel the target wheel turning, you absolutely need to rip the front apart. Again it is not a complete test as you will not know if the key sheared and the timing is way off but it is useful info while you are wondering what else might be wrong.
I am definitely interested in what the final outcome is and I really hope the OP gets it sorted soon.
Kevin
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oops, I thought you were swapping the PCM from a friends vehicle. That was why I wrote it the way I did. I should pay a bit more attention, eh :blahblah:
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Well I tested the wiring before and its a steady 5v on the two outer pins on the cps connector. If you know any other wiring tests let me know. I'm slowing starting to think I have the old ASP pulley and its bent the woodruff key. Its that or the sensor wheel on the cam is worn/damaged. Im sure the cams are turning but just out of sync. If they didnt turn id hear pistons hitting valves by now when I crank it. If the woodruff pin is bent it would still turn the cams. Either way I don't think im getting out of tearing it apart this weekend. Lets just hope I can put it back together!
Anyone: Is $2000 to rebuild this engine a good deal? If I cant figure it out I found a place that does a lot of 4.7s. Might buy some forged rods and pistons and let them have at it.
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Is that labor alone? Or is that complete with cast pistons, bearings, chains and balanced? If thats a complete short block thats not to bad at all.
Ask what they would charge if you provided the pistons & rods.... have them include balancing and see what they want.
NICK
Ask what they would charge if you provided the pistons & rods.... have them include balancing and see what they want.
NICK
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Thats everything from me driving/towed up to getting it back. I should say 2000-2500max because if the engine is a paper weight it will be 2500. They don't do forged or special stuff. If I bought the pistons and rods they would throw it in. Once disassembled they send the block to http://www.blainesmotors.com/index.htm to get checked out and possibly bored if needed.
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what ever happened with this?
i got a P0340 code a couple weeks ago, truck would crank but wouldnt turn over. i was at a pretty remote spot and my AAA wouldnt cover the towing fee. so i was able to get it started by playing with some sensors and fuses (not exactly sure what did it). anyway its been a couple weeks no since i reset the code and it popped back up today as i pulled in my driveway. truck was running and i didnt just try and restart it. im supposed to drive on the beach with a bunch of people tomorrow and now im nervous. i havent replaced anything yet but im thinking i may try to replace the camshaft position sensor however i've read alot that it doesnt always fix the problem. i hope it does in my case cuz i cant afford alot of down time. i really need to get on the beach tomorrow ( i know that sounds crazy but i have alot of people coming from far away to hop in my truck)
i got a P0340 code a couple weeks ago, truck would crank but wouldnt turn over. i was at a pretty remote spot and my AAA wouldnt cover the towing fee. so i was able to get it started by playing with some sensors and fuses (not exactly sure what did it). anyway its been a couple weeks no since i reset the code and it popped back up today as i pulled in my driveway. truck was running and i didnt just try and restart it. im supposed to drive on the beach with a bunch of people tomorrow and now im nervous. i havent replaced anything yet but im thinking i may try to replace the camshaft position sensor however i've read alot that it doesnt always fix the problem. i hope it does in my case cuz i cant afford alot of down time. i really need to get on the beach tomorrow ( i know that sounds crazy but i have alot of people coming from far away to hop in my truck)
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The Cam sensor is only like $20-25, if it were me I'd try and find one and throw it in before heading out on the beach. It might fix the problem for you, it might not but its a cheap enough thing to try and it can't hurt.
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Its on the side of the passenger side cyl head at the front of the engine, held in place by 1 10mm bolt.
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ummmmmmm i replaced the sensor on the passenger side at the rear of the engine with a 1/2" bolt. i originally pulled the sensor on the passenger side at the front with the 10mm bolt and it didnt look like the new sensor. what did i do? lol car started right up no problem, cleared the code and so far so good
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What was the outcome... Im willing to bet your problem was the Wooddruff key... 3-4 bucks and removal of your timing cover Chains & oil pump would cost much less than a new engine... Unfortunatley you would have to removed the timing cover to see if it is bent...
SPEED SAFE, NICK
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