Stalled, No Start, Code P0340 - JeepForum.com
 2Likes
Reply
 
LinkBack Thread Tools
post #1 of 17 Old 10-09-2019, 09:32 AM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
Stalled, No Start, Code P0340

2011 Grand Cherokee, 5.7

The Jeep stalled while driving and wouldn't start back up so I had it towed home.

I check fuses, all good. Tested all the relays in the fuse/relay box and all tested good. Tested the external relay from the TIPM recall and is good. I pulled the fuel line off the rail and there was definitely fuel pressure. I scanned for codes and got "P0340 Camshaft Position Sensor A Circuit Bank 1 or Single Sensor". The camshaft position sensor is cheap so I put a new one in it still won't start.

Anyone have any ideas?

krazykrames is offline  
Sponsored Links
Advertisement
 
post #2 of 17 Old 10-09-2019, 09:59 AM
jtec
Registered User
 
jtec's Avatar
2014 JK Wrangler 
 
Join Date: Oct 2017
Posts: 6,557
P0340-CAMSHAFT POSITION SENSOR CIRCUIT

keyword is CIRCUIT, be sure to keep old sensor and if you must replace use a jeep OEM part.

Will need a wiring diagram, DVOM BUT using a graphing scanner or labscope helps, as you observe CMP and CKP waveforms.

You use a GAUGE to check fuel pressure.
.................................................. .................................................. ...........................
TMI
Possible Causes
(K856) 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
(K856) 5-VOLT SUPPLY CIRCUIT OPEN
(K856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
(K44) CMP SIGNAL CIRCUIT SHORTED TO VOLTAGE
(K44) CMP SIGNAL CIRCUIT OPEN
(K44) CMP SIGNAL CIRCUIT SHORTED GROUND
(K44) CMP SIGNAL CIRCUIT SHORTED TO THE (K856) 5-VOLT SUPPLY CIRCUIT
(K900) SENSOR GROUND CIRCUIT OPEN
CAMSHAFT POSITION SENSOR
CRANKSHAFT POSITION SENSOR
BigTizzie likes this.

When I see the price of OEM I think aftermarket.
When I see the quality of aftermarket I think OEM.
jtec is offline  
post #3 of 17 Old 10-09-2019, 10:11 AM
ColdCase
My Reality Check Bounced
 
ColdCase's Avatar
2011 WK 
 
Join Date: Sep 2009
Location: New England
Posts: 14,243
jtec provides good advice, this thread may have additional detail to think about:

https://www.jeepforum.com/forum/f309...po344-4272865/

There was a discussion thread awhile ago on how to scope out a V6 cam sensor signal. V6 cams seem to have issues with reduced tone wheel magnetism and the sensor has a tough time picking up the reference signals reliably. It a similar procedure with the V8. What does the oil pressure look like?
BigTizzie likes this.

I have reached the age where all compliments will be followed by “for your age.”
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
Previous: 2000 Grand Cherokee Laredo I6, 1979 CJ7 I6 Quadratrac
ColdCase is offline  
 
post #4 of 17 Old 10-09-2019, 10:42 AM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
I'll sort through the info above, I've done all my own repairs over the last 20 years but this stuff is new to me.

I have a fuel pressure gauge set but not sure it has the connections for the jeep, I'll double check.

Don't know the oil pressure, the thing won't start.
krazykrames is offline  
post #5 of 17 Old 10-09-2019, 10:43 AM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
Oh ya, thanks for the super fast replies!
krazykrames is offline  
post #6 of 17 Old 10-10-2019, 08:27 AM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
Don't know if this is the correct procedure or not but with meter connected to ground, ignition on I tested the connector for the cam sensor. The supply wire showed 5v and the ground wire showed continuity. Not sure how to test the signal wire yet.
krazykrames is offline  
post #7 of 17 Old 10-10-2019, 09:36 AM
jtec
Registered User
 
jtec's Avatar
2014 JK Wrangler 
 
Join Date: Oct 2017
Posts: 6,557
signsl is observed using a graphing scanner - a labscope - the wave form is checked for continuity , no breaks as the harness is tugged, manipulated to simulate road vibration and shifting tension as engine moves. It is also Stacked to include the CKP signal as a bad CKP can cause this code IIRC.

If I am into jeep website later if I can I will capture a good wave form BUT the issues is not a bad rreading but no reading the break in signal would be easy to see.

Might want to check wiring sensor to PCM, the connectors and the first several inches of CMP connector wires for issues, thats where the wire often fail.

When I see the price of OEM I think aftermarket.
When I see the quality of aftermarket I think OEM.
jtec is offline  
post #8 of 17 Old 10-10-2019, 04:19 PM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
I don't have a graphing scanner, not sure I would get one for this one time use. I suppose I could use a standard multimeter, it wouldn't read the waves as they would fluctuate to fast, but at least it would read something, right?

If checking the wiring, sensor to PCM, how in the world do I know what wire going to the PCM is coming from the sensor??
krazykrames is offline  
post #9 of 17 Old 10-10-2019, 07:04 PM
ColdCase
My Reality Check Bounced
 
ColdCase's Avatar
2011 WK 
 
Join Date: Sep 2009
Location: New England
Posts: 14,243
You won't see anything useful with a multimeter, you'll want to check signal integrity. So so you need a typical scope. The scope is more useful for erratic conditions, misfires.

You can get a 2 or 3 day pass to tech info from techauthority.com for about $35.

Below is a circuit diagram that may be relevant. A shop/dealer will have a special breakout harness for testing. You should also be seeing about 5 volts on K44 with the sensor disconnected, which is the CMP sensor signal from the PCM. With ignition off, you should see an open circuit between K44 and the K856 5 volt supply.

I'd double check that the camshaft sensor is installed properly and not defective. If all these check OK and you tried another sensor, then its time to inspect the camshaft sprocket.

This fault gets set when the crankshaft revolves 2.5 times but the PCM gets no corresponding signal from the camshaft sensor.

Connectors on these WK2s seem to be susceptible to corrosion.

Now all thise assumes that the P0340 is causing the no start, not something like being out of gas
Attached Thumbnails
Screen Shot 2019-10-10 at 8.46.58 PM.jpg  

I have reached the age where all compliments will be followed by “for your age.”
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
Previous: 2000 Grand Cherokee Laredo I6, 1979 CJ7 I6 Quadratrac
ColdCase is offline  
post #10 of 17 Old 10-11-2019, 07:26 PM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
Used an endoscope to take a picture inside the hole where the cam sensor goes. Up is actually to the left. The smooth surface all around the outside is where the sensor slides in.
I'm assuming the thing in the middle of the picture is what the sensor reads? Part of the camshaft? Should I see that rotate when the engine cranks?
Attached Thumbnails
19-10-11 19:42:07_1570842939124.jpg  
krazykrames is offline  
post #11 of 17 Old 10-11-2019, 07:49 PM
ColdCase
My Reality Check Bounced
 
ColdCase's Avatar
2011 WK 
 
Join Date: Sep 2009
Location: New England
Posts: 14,243
The tone wheel is located at the front of the camshaft. I think that thing with the notch you see is the so called tone wheel. When the cam gear is rotating, the sensor will detect the notches. Input voltage from the sensor to the PCM will then switch from a low (approximately 0.3 volts) to a high (approximately 5 volts). When the sensor detects a notch has passed, the input voltage switches back low to approximately 0.3 volts. So, in theory, you could attache a probe(s) , manually spin the engine slowly, and see the voltage fluctuate. If so, the sensor is picking up the timing signals.

I've heard of a bad phaser (variable valve timing) suspected to cause this code, but the engine should start but may run poorly.

The tone wheel will rotates with the engine. Its an interference engine, if the cam is not rotating with the crankshaft, you will have valve contact with the piston.

The tone wheel looks something like this:
Attached Thumbnails
Screen Shot 2019-10-11 at 9.57.12 PM.jpg  

I have reached the age where all compliments will be followed by “for your age.”
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
Previous: 2000 Grand Cherokee Laredo I6, 1979 CJ7 I6 Quadratrac
ColdCase is offline  
post #12 of 17 Old 10-11-2019, 08:08 PM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
It does appear to be the tone wheel. I took a video with the endoscope while cranking the engine, it definitely doesn't spin, at all. Does that mean what I think it means?
krazykrames is offline  
post #13 of 17 Old 10-11-2019, 08:28 PM
ColdCase
My Reality Check Bounced
 
ColdCase's Avatar
2011 WK 
 
Join Date: Sep 2009
Location: New England
Posts: 14,243
How many miles are on the engine?

This guy changed his chain at 300,000 miles, gives you a pretty good view of the chain area and wheel.


I have reached the age where all compliments will be followed by “for your age.”
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
Previous: 2000 Grand Cherokee Laredo I6, 1979 CJ7 I6 Quadratrac
ColdCase is offline  
post #14 of 17 Old 10-11-2019, 08:31 PM
ColdCase
My Reality Check Bounced
 
ColdCase's Avatar
2011 WK 
 
Join Date: Sep 2009
Location: New England
Posts: 14,243
There was some talk of timing chain defects in that era Dodge and Chrysler cars.

https://www.hotrod.com/articles/chry...-chain-defect/

https://www.challengerforumz.com/thr...defect.115406/

I would think there would have been a bunch of other codes if the timing chain broke... but dunno. Anyway, if thats the worst case you are pretty much into a reconditioned engine replacement decision.

The valves have already kissed the pistons bending them enough to no longer seal compression. Most likely one or both of the heads are trashed due to the fragile valve guides and not worth trying to repair them. The short block, other than some small contact marks on the piston tops, is most likely fine other than the small bits of the broken timing chain guide that have gotten into who knows where.

I have reached the age where all compliments will be followed by “for your age.”
Current: 2011 Grand Cherokee Overland V8, 2009 Liberty Rocky Mt V6
Previous: 2000 Grand Cherokee Laredo I6, 1979 CJ7 I6 Quadratrac
ColdCase is offline  
post #15 of 17 Old 10-11-2019, 08:42 PM Thread Starter
krazykrames
Registered User
 
Join Date: Jul 2014
Location: Chatfield
Posts: 23
Quote:
Originally Posted by coldcase View Post
how many miles are on the engine?
185,000
krazykrames is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome