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Timing issues Help

Sounds like you got it figured out, as unfortunate as it is. Maybe if its covered under warranty you could get a replacement, or if RockAuto was nice they could give you credit towards the Delco, or just pay the local store price and still try to get a refund from Rock Auto, or credit anyway.
 
Well after a pause to buy a new Crankshaft Position Sensor, another $70.00. I put it in and get the same results as before. I have moved the IP both directions. The biggest problem is in GMTDScan Tech, when I command a time set it stall the engine, so I can't even see what the "Actual Timing" is. Also if I go into TDCO Learn this also stalls engine. I am so F'ING pissed at this right now. Don't know where to go!!! HELP Maybe the ECM is F***ed but I don't have a spare chip to test it.
 
AC Delco and Standard part where identical, same number stamped on them. With earlier post where I unplugged the Optical Sensor and tried running with just the CPS (and it would not) I thought we were on to something! Maybe I can do some voltage checks to ECM or if someone has some old parts they can send to test, I don't mine paying for parts that I know will fix the problem.
 
I have a 94 ecm you could try but it's for a 5086 pump. Ithink that's the right number it's the oddball high output. You might be able to try your chip in it.
 
Thanks for the reply AK, Does the ECM have a chip in it now? I wouldn't mind having both because I suspect it must be one of them. Everything we diagnosed before pointed towards the new CPS I put in as a proactive measure. That along with the HG job there should not have been anything else to cause this problem. But with both CPS doing the same thing it has to be the ECM or chip. It is a 95 K2500 LD with the Auto & 3.73 gears

Standard Motor Products PC125
AC Delco 213-337
Both translate to GM part# 12557046 which is stamped on both sensors

Unplug Optical Sensor and engine won't start/run with CPS still plugged in
Unplug CPS engine will start/run with the Optical Sensor still plugged in

GMTDScan Tech will cause engine stall when commanding TDC Time Set
GMTDScan Tech will cause engine to stall when doing TDC Learn will sometimes pick a number but usually wants to grab 2.02 and then I get the code 88
Engine temp is over 180* and codes cleared before any/all attempts to do Time Set and Learn
Presently got it to grab a -0.53 I think
I have tried moving pump a CH each way, but without knowing the Actual Timing from Time Set I don't really know which way I SHOULD go

I have done a slight Optics bump as a trouble shooting measure as stated above.
I seem to remember watching the advance and seeing it move when revving engine

Cold start will run like she-at and smoke the neighbours out, once warmed up runs strong, smooth and smoke free.

Is there a test I can do to check the CPS connection at the ECM? I would suspect the CPS generates a magnetic pulse to the ECM is this correct and how can I test that?
 
I went back to the start and reread some of it and MO is your IP is pooched. If you want to try my ecm that's fine it does have the 5086 chip in it tho.
 
Not what I wanted to hear, It ran good before the HG job and I could set timing, what could have change or gone bad with IP? If the ECM and chip are compatible enough to give a accurate test I would do it, but the cost of getting it to me and back again good be fairly costly. It would be worth it if it determined the problem was one of them but costly if it did not and I am still scratching my head. Thanks
 
Oh great IP gurus what is this connection on the IP and what does it do? I was just checking all the connections and the boot is seated properly so I do not know if the electrical connection under the boot is tight.

12--20050902113827.jpg
 
Found out it is the fuel solenoid. Another question related to the Timing Stepper Motor. I am wondering if when I had everything apart to do the HG if it is exposed enough that I might have banged it and dislodged something. Maybe that why I can see it move but it is not moving the timing ring enough or at all.


TSM.jpg
 
I have got a small mechanics mirror and am going to have a look tomorrow. If that what it is I would have to pull the intake off but the price of repairs would be cheap. When TDC Time Set is commanded it tries to put timing to base IP timing and maybe this is where it is having problems. Got my fingers crossed.
 
Mudbath said:
OK here is what the tests revealed

Historic had a code 34 to start with (they crop up randomly )

Unplugged the CPS was hard to start but ran once started (produced a DTC 19 Crankshaft Position reference Error as expected)

Plugged CPS in and unplugged the OS was really hard to start and would only run (rough) if I gave it throttle...let off throttle = engine die produced a DTC 17 High Resolution Circuit Fault and a DTC 18 Pump Cam Reference Pulse Error as expected

So using OS - CPS out of the equation engine runs

and using CPS - OS out of the equation engine stalls and runs rough

This is telling me that the CPS that I replaced during the HG job TO BE PROACTIVE :WTF::mad2: is flaky, It was a Standard Motors Products PC125, has anybody used these before?

What bugs me is when I unplug it it gives a Code 19 and in GMTDScan Tech snapshot there aren't any Crank Reference misses, so some of it is obviously working!

What are your thoughts 6.5 gurus?
Click to expand...

I just went through your thread, Is the bold part in your quote saying the CPS is connected and the OS is disconnected? If that is the case it would point to a bad IP. It will not run great with the OS disconnected but it should run.
 
One other thought, do you still have an optical filter harness in the OS connection?
 
No optical filter. If I unplug OS and try to start it it won't, but if I unplug the CPS and try to start it will start and run (not well). With the CPS unplugged maybe the ECM tries to go to base IP timing and with the TSM damaged or disconnected maybe it can't so won't start/run. I do not want to ever hear bad IP again!:D Can't afford that and to much work after just doing HG and water pump
 
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