joeban

Hello,
My 1999 ml 320 Crank positioner sensor CPS keeps going bad. I have change it three times. it will work for few miles then then check engine light with code P0335 shows on the scanner. Des anybody has this happened before? i have changed coils, sparkplugs and fuel pump... it did not cure it. Thank you for your input.

art_arev

What CKP have you bought? If it is not Bosch, then buy one. Fit the bosch CKP sensor, erase the codes & drive.

joeban

Yes on all 3 instances they were Bosch. this is the strange thing. they are installed they work for 10 miles on approx 3 occasions. after they start giving misfire codes and finally the P0335 bad CPS. Any body experienced 3 they ago bad one after the other? do I need to reset anything else other than the code in order for the CPS to keep working? Thank you for your help. I am stuck on what to do other then take it to the dealer for another CPS.

DrX

Bad CKP sensor doesn't cause misfires - it causes stalling. Is the engine cutting out, or just starting to run rough?

If it's cutting out, then the next thing to replace is the wire connected to the CKP sensor.

If it's not cutting out, the new CKP sensor is OK. Look into other causes of misfires, like clogged cats.

joeban

Thank you for your reply. What is doing now is not misfiring after the third change of the CKP. Last break down was when I drove it on the highway for 15 minutes and all of the sudden lost it's poer and died. I was able to start it rightaway and drove it for 100 yards and died again. It kept doing the same same thing (start it and dies few seconds) till i gave up and towed it to the house. second day i started it with no problem and let it run in the driveway for one hour with no issue stalling. I noticed if I drive it on the highway on a higher RPM that might do it (stall).Like I mentioned prevoiusly. Changed Spark plugs, Coils , Gas pump, MAF and the CPS. I feel I a running in a circle where I started by changing the Fuel pump at the Mechanic shop.

DrX

Tell us what was happening before you changed the CKP sensor the first time. Misfires? Stalling when warm? Long-crank-no-start or start on 2nd or 3rd attempt? Did you have P0335 code before you replaced the fuel pump?

Obviously changing the CKP sensor didn't fix the problem, twice. Look elsewhere.

You can assume the latest CKP sensor is OK. Was the connector damaged during the swap? Is there corrosion at the connector? Was the wire bent or damaged during the swap? If the CKP signal is interrupted at any time, you'll get stalling.

joeban

Thank you. it stated by stalling on the highway. It will start after stalling then you could drive it for 500 yards then it stalls again. it repeats the same behavor but at a shorter distance till you get to the point it will start then it dies rightaway without you being able to move anyfurther. I towed it by that time it was not starting even I left it overnight. The Mechanic did a fuel test and findout a fuel pump went bad. The fuse for the fuel pump kept blowing up. replaced the fuel pump but not the fuel filter. I got Po335 the third replacment to CKP. Now it starts but with no error codes after i reset the codes to see if I get the P0335 (leaving it runing for 1 1/2 hour for the code to show up. I know I am rembling but this is driving me crazy trowing parts with no end in sight. Thank you for your help

DrX

So it was stalling frequently before you changed the CKP sensor the first time, but now it doesn't stall all the time? Now you can start it and run it for a 1/2 hour?

joeban

After the last episode of stalling and starting. I left for 3 days without starting it. last night I started it and let it idle for 1 1/2. it stalled. tried to start it it was cranking and not starting. the symptous on CPK. the check engine light came on with P0335. Thank You

joeban

sorry meant to say 1hour and 1/2. thank you

Maj. Dundee

Check your motor mounts.

1. set the parking brake and open the hood.

2. start engine to warm up temp.

3. step hard on brake pedal and place into drive.

4. then snap the gas pedal and see if the engine rises and or you hear a thump.

joeban

thank you for your hep.. I just got the time to work on it. Whemn I try to start it it cranks and do not starts. last time i started it. it started and I let it run in idle till it died as i stated on my previous post. So now it does not start i guess till I install one more (3 up to now) CPS So I understand what is the motor mount has to do with a bad CPS. Thank you

ItalianJoe1

When the original cps failed, was there oil in the connector? It may be contamination in the harness rather than just a bad sensor. Really you need to scope the sensor and compare the waveform to a known good car but this is beyond the scope of the average mechanic. I'd suspect a wiring issue is the culprit, or there is some debris keeping the sensor from seating all the way down causing an erratic signal.