I've been intermittently having the classic hesitation/stalling/no power issue for several months now. My 'C' has 130,000 kms on it and is religiously maintained. It kept throwing a P0300 code at me that would disappear after 3 successfull "trips". Only this code, nothing else. I read through the TSB's and all associated literature (this site is awesome) with regards to this code. I also read about the SeaFoam product and decided to give it a try for $15. After trying the spray shot SeaFoam into my 4 cycle lawn mower and immediately found a noticable difference in performance and overall quieter operation. I could actually hear the engine "smooth" out as I sprayed SeaFoam into the carb. So into the Hemi she goes. I removed the engine cover and used the large vacuum hose on the right side of the intake runners. I poured about 1/2 a 16 ounce can slowly into the vacuum line. The Hemi stuttered but kept running. Shut down and wait 8 minutes. Fired her up and rev to 4500 or so - the smoke was wild but the Hemi ran fantastic and throttle response was markebly improved. I put her in first and drove about 2 kilometres maintaining about 4500-5000 RPM. The smoke eventually petered out. The Hemi ran fine, but still stumbled when punched. I drove home, about 15 kilometres, and pulled the codes again using the key acc/on method. Now I get, P0016, P0300, P0315, P0335, P0339. All, except P0300, point directly toward the crankshaft positioning sensor.
P0016 - crank/cam timing misalignment
P0315 - no crank sensor learned
P0335 - crank position sensor circuit
P0339 - crank position sensor intermittent
SO, today I will pick up a crank sensor from Chrysler and install it. I understand they are about $30. The sensor is located behind the starter motor. Standby for results.
NTF: I also ran SeaFoam through my 44,000 mile '95 Ford Thunderbird Supercoupe. This car is pristine and has been babied since new. It also feels "better" (throttle response, quieter, smoother etc.) but it did not smoke a fraction of what the Hemi did. The smoke is caused by loosened carbon deposits being burned off. So the Hemi did have quite a build up of carbon regardless. At this point, I have to support the SeaFoam product. Three engines with all three showing marked improvement. I understand pouring 5-7 ounces into your crankcase about 100 miles before an oil change will breakdown carbon, varnish and oil deposits that will be drained away. Again, I will try this on a 4 cycle lawn mower. Fresh oil, then a SeaFoam treatment, cut the lawn and then drain the oil for a visual. Standby once again.....
Crank Positioning Sensor. $43.76 out the door from local Mopar Stealership - jobber discount.
- Disconnect positive battery cable - the starter has hard battery to it's terminal!!
- Remove qty 3 15mm bolts holding the starter to the block - easiest with air ratchet as wrench space is limited, but a hand ratchet will work with patience. Require 6" extension for lowest bolt due to bell housing casting.
- No need to disconnect electrical as starter will sit out of the way on top of front sway bar.
- CPS now exposed. Use flat tipped screwdriver to push red locking pin on CPS connector "up". You will hear it click.
- Remove one 10mm bolt holding CPS to block. Pull out CPS - This requires quite a pull as sealing ring gasket is tight - look at new CPS as reference.
- Use a smalll flat tip screw driver to unlock connector from CPS - It's far easier to do this now as the CPS's installed position does not allow easy access to this lock. Again, reference the locking "hump" on the new CPS.
- Lubricate the new CPS's sealing ring gasket and reverse disassembly procedure. The last few turns on the CPS bolt will pull it up tight against the block. You will notice you can't push it all the way to seat by hand.
I live rural and drove to the city and toured around town and then home again ~100Km or 60 miles round trip - punching the pedal when the opportunity arose.
- Secondary highway into town ~ 90km/h / 55 MPH
- Around town - Stop and go ~ 60km/h / 35 MPH
- Return on freeway - up to 140 Km/h / 80 MPH
I got me Hemi back!! Unhooked ESP and laid down qty 2 strips of Falken.......
Pulled code using key method - nothing! Only a "Done".
- car hesitating and stuttering - no pattern, occured anytime - Code P0300 only.
- ran SeaFoam product through engine - no change in performance issues but now throwing P0016, P0113, P0300, P0315, P0335, and P0339.
- most codes point to crank positioning issues.
- changed CPS.
- performance issues resolved - car runs like new. Can barely hear it run when outside the car at idle.
So, I suggest applying the SeaFoam cleared the carbon build up in the cylinders, but the carbon "demon" may not have caused the original P0300 code. I figure the CPS was intermittently failing, causing the original P0300 code and the SeaFoam application (clearing out the carbon) somehow "allowed" the subsequent codes (that pointed to the CPS) to be captured. Perhaps it was simply FM - (REMOVED)Magic. Comments and suggestions are encouraged. Would having the battery disconnected for about 90 minutes clear any stored codes?
So, those of you experiencing P0300, you may wish to try $14 worth of SeaFoam and $40 worth of CPS before dropping $1K on mechanic time.....
Enjoy your day. I'm off for a sunny, rock 'n roll filled cruise up the Valley in my revitalized Charlie ...... :o)
1. Lawnmower experiment concluded that SeaFoam does clear out carbon desposits. A 60 minute lawn cutting on fresh oil produced oil that looked very used.
2. One half a bottle, 8 oz, of SeaFoam into the Hemi crankcase before the 100Km "test drive", then peformed oil change. Removed oil showed colouration and deposits near end of draining procedure (bottom of pan stuff).
3. I suggest SeaFoam performs as advertised and will be run through all my internal combustion engines.
I know this thread is closed but I wanted to update this with some more CORRECT INFO on the location of the Crank Position Sensor.
The crank position sensor on this motor is on the PASSENGER SIDE whereas the starter is on the DRIVER SIDE. Opposite sides. That was a real bummer to discover after sitting underneath the car for 2 hours desperately trying to locate a non-existant sensor behind the starter. There is a sensor there, but it is the Knock Sensor which has a twin located on the passenger side as well.
I had the same issues as above, car feels peppier and the CEL is gone, but I only drove it for about 15 minutes. I hope this solves it permanently.
One hand on the wheel and one on the bottle, one foot in the grave the other the throttle!
i got the same intermitant problem on the same car !! replace serpentine belt for a shorter because my a/c comp clutch is going out and i dont have money (450$)too fix that trouble first i need to go to work ,, i read that could resolve my problem of misfireing but it dont.... replace de cps for a napa grinding rust around de engine block and the problem stay there ... replace all spark plug buy at my dealer ,,, sorry i dont gap the spark plug before installing ,,,and the problem wont to go ,,,,i spray some break cleaner over the intake too see vaccum leak look to be ok no idle variation run ok on highway perhaps at traffic light its another story ruff idle and shake as hell !!i clean the throttle whit mopar stuff sorry i no its an old post but i need help
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