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signet
01-19-2017, 11:28 PM
truck stuttered and then quit; as had done several times before.
History;
a year ago truck quit when hot, restart when cooled down. a friend who is a electrical guru said it sounded like crank sensor. neither had a scanner, so he hooked up hand held scope to wires for crank sensor and confirmed.
replaced and all was well.
coupla months ago, it started to stutter again. i said it couldn't be the sensor again, the first one lasted 150k. crawled under and found he left the connectors for his scope on wires. he cut the covering off the last 6" before the sensor. the tabs were arching to trans and causing miss. covered with good electrial tape and seperated and all was well.
yesterday it stuttered again a coupla times and quit. got p0336 code.
replaced sensor, no change. played with wiring and got it to start, but bucking and stuttering on any even mild acceleration.
went to bone yard and cut off 16" of wire and connector( turns out almost ANY merc form 1998 thru 2007 had same sensor,) so was able to get new wire and socket he damaged:
ALL TO NO AVAIL>>HELP, im outa ideas!!!:yell::yell::bow::bow:

Aqua Puttana
01-19-2017, 11:56 PM
...
ALL TO NO AVAIL>>HELP, im outa ideas!!!:yell::yell::bow::bow:
Have you checked for DTC's Diagnostic Trouble Codes?

Did the symptoms change with the connector/wire replacement? What are the present symptoms?

Did you keep the proper polarity? (If it matters... I'm not certain.)

Were the wire connections butt spliced, wire nuts, soldered, etc? Some signals are picky as to connections.

Is it 100% certain the same connector? Sometimes there are subtle differences.


vic

signet
01-20-2017, 12:15 AM
used butt conectors w/ heat shrink ends to prevent arching. used on merc that had same part number. does the whole wire need to be covered?? he removed the covering before he attached the leads. had green wire and one green w/white strip. made sure to match. made connection to be beyond his work..what a bi**h!! no space to work.someone mentioned a chaffing on harness?? where??:wtf:

signet
01-20-2017, 12:26 AM
still get the p0336 code other than the always one for glow plugs.
it will start fine, turns over several times, but starts, runs smoothly at idle but as soon as you start bringing up the rpm around 16/1700 it breaks up badly . all in neutral, would hate to try in gear!!

Aqua Puttana
01-20-2017, 12:59 AM
Apparently the P0336 DTC can be a red herring so don't get tunnel vision.

This a gas engine, but the principles should still apply to MB codes.


Update (and likely my last post on this topic): The Mercedes dealer has confirmed the gas is bad. They are recommending replacing the fuel pump as well as the other parts I listed in my previous post. All that remains is working out the cost details between the dealer and the insurance company.

So, in summary, the P0336 code turned out to be a red herring. Moral of the story: If your car dies not too long after you fill the gas tank, pull a sample from the tank before your worry about the codes. If I had done this, I would have saved myself a few days of scratching my head. However, in my defense, there are far more instances of failed crankshaft position sensors than bad gas. C'est la vie. Turn the lights up and roll the credits - show's over ;-)

http://mbworld.org/forums/e-class-w211/544665-p0336-code-no-start.html

... runs smoothly at idle but as soon as you start bringing up the rpm around 16/1700 it breaks up badly . all in neutral, would hate to try in gear!!
Have you tried disconnecting the MAF sensor?

Maybe EGR related problems?

vic

signet
01-20-2017, 01:23 AM
do some more checkin in a/m. lost 2 days already, got to get it figgered out soon!! thanks for suggestions

SneakyAnarchistVanCamper
01-20-2017, 04:18 AM
... cut the covering off the last 6" before the sensor... covered with good electrical tape... played with wiring and got it to start,

Well there's your big hints if you ask me. Your computer is telling you that your CPS is reading out of range. The wires' insulation on the CPS was damaged (6 inches worth of stripped wire? wth?) and then most likely exposed to water/humidity (because of its location). These are the facts.

I think your reoccurring issue points to resistance in your CPS wires, created by the damaged wire corroding over time, and then too much resistance being added when you spliced on the new wire and connector. A CPS generates around 2-6v afaik. A small amount of resistance could foul up these small, delicate signals, I would think. Playing with the wiring and getting it to start is a dead giveaway that those wires/connectors have resistance in them, causing the issue.


Also, the fuse or harness may be damaged from the shorting, try swapping fuses or voltage drop test across the fuse/either side of the wire in question.

As for chafing on the wiring harness, behind the fuel filter:

signet
01-20-2017, 06:50 PM
truck starts fine. runs smoothly up to 18/1900 rpm and then misfires. it will accellerate as long as you dont push it hard. will pull up hills and overpass when up to speed. only after 2000 rpm it wont go. battery voltage good. scanner doesnt show anything other than p0336. have checked wiring and have not found any rubbed wires as yet. drove around this a/m and worked fine as long as not pushed.
where that distributor located???::censored:
wire was only pierced w/tabs for hand held scope, but wires were bared when removed. went back beyond that area to splice.

signet
01-20-2017, 06:53 PM
you mentioned replacing fuse related to this?? which fuse would that be. dont remember seeing one for that. thanks

signet
01-20-2017, 08:36 PM
noticed when running scan 1/2 hr ago, had no voltage to oxygen sensor. does it mean its bad, or a different problem?? i would pull my hair out, but i have none left!!

SneakyAnarchistVanCamper
01-20-2017, 10:38 PM
The code is telling you exactly what is wrong (most likely). Bad connection to crank sensor or bad crank sensor/adjustment. Inspect the face of the CKP sensor for dirt, cracks or scraping. Ensure it has a gap of a few papers widths.
Try squeezing on your butt connectors with some burly pliers on the CPS wires that you modified. Test resistance from one end of the CKP wire to the other end. If resistance is confirmed, trace the CPS wire back to its origin and completely replace the wire.


noticed when running scan 1/2 hr ago, had no voltage to oxygen sensor. does it mean its bad, or a different problem?? i would pull my hair out, but i have none left!!

"An oxygen sensor will typically generate up to about 0.9 volts when the fuel mixture is rich and there is little unburned oxygen in the exhaust. When the mixture is lean, the sensor's output voltage will drop down to about 0.1 volts." (may not exactly apply to sprinters, generic info)

I dunno, was the engine running? Unplug the MAF sensor, does the problem continue?