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crankshaft position sensor

matuva

matuva

Tropical 6.5er
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Location
New Caledonia. An island in south west pacific, cl
Hi,

is there anything special wich must be done, such as KOKO routine or something else, when you change the crankshaft position sensor?

The one on the truck is GM part # 10154687, wich doesn't appear anymore in the catalog.
According to cross reference catalog, this part # equals AC Delco 213-337, wich is GM part # 12557046.

So, we bought a brand new 12557046 and put it on a 1996 K1500 (a Cheyenne, not mine).

The engine starts, rev, and die --- :skep: and on, and on...

So we ended up putting back the old one, the part # 10154687, and the truck started right away...

there's something I don't understand. What the heck is this 10154687 :confused5:
 
I recently changed mine, was getting a random code saying it was in error, and the hard part was getting the old one out. That took all day, as the plastic in the housing was brittle and would just crumble....
after installing new one, a standard ignition part, had no more trouble with it... no relearn or anything....
 
94K30 said:
Come to think of it, SSDiesel's website states that you will need to do a relearn after changing the crank sensor...
Click to expand...

i'd call heath diesel and ask bill or ian to get a definite answer for the question or wait for one of the gurus to answer it for you. the truck should run. i do know that with a bad crank position sensor the engine will stall. defective new part perhaps?
 
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now that I have thought about this, I recall someone telling me that about 1/2 of the time, it will need a relearn, the rest of the time you get lucky... I guess I got lucky.
contrary to Dave's post, mine never stalled when crank sensor was bad, it just posted a code for crank position sensor error repeatedly.
 
According to 1998 GM manual it has to be learned , for life of me I can't figure out why, unless there is difference in resistance sensor to sensor, but it is a speed pickup with no gap adjustment.

For Ko/ko learn you mite have to put the CTS in a pot of hot water to set/meet the >170F + to initiate the learn, but also according to manual once you achieve 170F coolant after ko/ko learn command has been initiated it will learn then also, so I guess from manual description ko/ko learn waits for 170F then pcem learns position.
 
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Hi Tim,

well thanks for these inputs. It looks like we're going to have a funny week end to fight with this sensor.
the first goal will be to make her start with the new sensor. If we succeed in, I will try to force the relearn with AutoEnginuity, but first, we have to make her start...
 
CPS again...

last time, to solve the problem, we put beck the old CPS #10154687 in place of the # 12557046 (supposed to be the newest ref.)
The truck still shows code P0335 buts accepts to start and run.

With the #12557046 we tried everything : KOKO routine, when we succeed in starting the engine, TDC relearn, disconnecting batteries, disconnecting + an - and grounding them, disconnect the CPS, disconnect the optic sensor.... nada. The truck is still very very hard to start and runs rough, idling at 800~900 rpms and still showing DTC P0335.
So, that's why we ended up putting back the # 10154687, wich shows P0335 code but allows the truck to start and run almost fine.

The guy is gone inland for a week now and won't be back before 10 days. We had no phone call, so I bet the truck is running.

Yesterday, we had another 1996 K1500 with code P0335. We took out the CPS and I saw it was a # 10154687. It was broken... So we had no choice, we had to change it.
I thought myself "God, not again..."
So, we took another brand new # 12557046 and put it in place--- and again, things turn crazy.
The truck started. 1, 2, 3 times, and then never did again... We killed the batteries by trying to run it...
New batteries, new PMD (just to check) and the truck fired up. We shut off, andshe never restarts.
We disconnect the batteries, connected back the stock PMD, and she fired again, we shut off, and she never restart, and so, and so....
During all this time we never succeed in clearing code P0335, it was present at any time and reappears as soon as you erase it.

So, does any of you can access GM parts book? Any can tell me what the heck are these CPS GM part # 10154687? They are supposed to be discontinued and replaced by GM # 12557046.
I saw today (Rockauto) that the GM# 12557046 itself is discontinued and is now replaced by ACDelco 213-337 :crazy:

In the name of God! Anybody have any idea of what happens? What did we do wrong, I think we don't made any mistake about the part # and use the right CPS , at least I'm wrong, so...:svengo:
 
according to manual, with sensor connected the 'a' terminal or probably yellow wire should show 4 volts or more when cranking engine. the other wire should be black as the ground. faulty sensor if >4 volts.

10154687 part is invalid
12557046 is good sensor #
2000-1994 6.5L (F) 393" Diesel Crank 12557046 22124
1995-1994 6.5L (P) 393" Diesel Crank 12557046 22124
1998-1994 6.5L (S) 393" Diesel Crank 12557046 22124

10154687 22124 crosses to 12557046 22124--parts match
sensor should read between 500 and 900 ohms-compare both sensors,
while cranking the engine you should see at least 20 mV on the AC scale,
could the sensor be contacting the reluctor wheel, both exact same length? gap is usually within .050 in. of the reluctor wheel
 
You can jump the ECT sensor to fool ECM into thinking it is at correct temp....or use a potentiometer and set the ohms across the connector anywhere from 177 - 240.

Clear the codes with the key on engine off (ECT jumped).

Try a KOKO relearn.

It should take....
 
Finally....


  • put a new CPS, ACDelco 213-337, crank and still no start;
  • disconnect batteries, wait, reconnect, crank and still no start;
  • batteries connected, swap to a 1997 PCM, crank and still no start;
  • wait for a while, put back the stock PCM (1996), crank, starts immediately, runs like a charm. No codes.
  • Shut off, key on several times : restarts fine and iddle perfect,
  • then DTC P1218 shows---

but she now starts and run fine. We yill see in the day coming if DTC P1218 remain...
 
Matuva, did you ever found out what is wrong with the non-working replacement CPS?

Is this another part that has to be ACDelco branded? like OPS.
 
This ACDelco 213-337 CPS is a rebadged 12557046, same as the STANDARD PC-125.

I'm pretty sure the previous one is fine too. I have kept it and wil try it on the second truck having same problem.

In fact, I believe the key is to disconnect the PCM ( I did it with batteries connected, don't know if it is a key point too), wait for about 10 mns to clear internal memory and reconnect.

That's what I did and the miracle happens :arf:
 
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