snw blue by you Posted January 29, 2010 Share Posted January 29, 2010 I have not been on for quite some time as I am busier than a one legged man is a butt kickin contest, and it pains me to return and seek help but here goes. We have a '98 Louisville in the shop that has a crank no start. Engine serial # is 6TS03744. It has a CMP sensor only. I am not the tech working on the truck but I have had to look at this thing for the last 6 weeks. Enough is enough. Some type of work was performed on this by a tech that is no longer with us a few months ago. It was brought back in due to a massive oil leak at the front cover. It was found that an o-ring had failed, and I guess it was the fault of the installer. As a result the front of the cam mushroomed. That was repaired, and the engine reassembled. Now it cranks, tries to run but will not. It was driven into the shop. The timing has been verified, however, and I don't know if it makes a difference but the procedure used was for the 3406 with a CKP and CMP sensor. The only info relayed by the ECM is no engine speed, which is obviously the root cause of the no start but the problem the tech has is that we do not have the correct manuals to troubleshoot this thing. Can someone help please! Thanks in advance, Stephen. Quote Link to comment Share on other sites More sharing options...
LARRY BRUDZYNSKI Posted January 29, 2010 Share Posted January 29, 2010 Smoke or no smoke out the exhaust? Ran across one before with a missing/chipped tooth on the tone ring. Being the fact that you had a cam issue, I would suggest checking it. Quote Link to comment Share on other sites More sharing options...
snw blue by you Posted January 29, 2010 Author Share Posted January 29, 2010 Larry, As long as the tech is cranking it, it smokes, even sounds as if it may start but if he ain't holding it is start, it's dead in the water. The scan tool shows engine RPM, however, there's that message. I kinda figure something with the tone ring or sensor but honestly, I'm not sure, and I don't know what to do for testing of the sensor or the ECM system itself. The truck is being worked on by a kid that has potential and wants to fix this thing but I think he got in over his head. I'm just trying to feed him any info I can to help him. Quote Link to comment Share on other sites More sharing options...
LARRY BRUDZYNSKI Posted January 30, 2010 Share Posted January 30, 2010 Any chance of re-reading thru the other techs notes on this job. What was removed or messed with before this problem happened? What was the original concern/complaint? Help us to help you...... Quote Link to comment Share on other sites More sharing options...
ktmlew Posted January 30, 2010 Share Posted January 30, 2010 Just for shits-an-giggles I would pull the can sensor and look in the hole while baring the engine over. Do these have a "tab" or a tone ring on the cam for the sensor? I would measure the distance to said tab/tone ring and see if it matches the original cam...any way to do a compression test? That should rule out timing issues. Quote Link to comment Share on other sites More sharing options...
dieseldoc Posted January 30, 2010 Share Posted January 30, 2010 A 6TS has only a cam sensor located in the side of the front cover. Timing calibration on a one sensor engine like this can only be performed with the timing probe installed and ET or ECAP. Are the battery connections clean and tight, fuses ok and in place, Batteries have a good charge(sounds obvious, but has bit me in the ass before). There is sometimes a ground stud on the left side of the cylinder head, some trucks use this stud and some do not. if your engine has this be sure it is clean and tight.Is there any fault codes active? Is the cam gear timed and backlash set correctly(a tooth off one way or the other can cause grief).This engine should use a 126-8481 shim with the timing sensor. However if the the slip head of the sensor is black and has a flat face DO NOT use the shim. The procedure is to remove the sensor and be sure that the cam gear is in a position that one of the valleys of the "tone ring" is not at the opening for the sensor. Look in the hole with the sensor removed and slowly turn the engine over, you will see what I mean. May not be a bad idea to make a few revolutions to make sure things look ok, nothing wobbling or dings in the gear. Using a small screwdriver pull the slipper head of the sensor all the way out. Thread the sensor in and torque to 30 ft/lbs(snug it up). Remove the sensor being sure not to bump the slipper head upon removal. Install the shim and than install the the sensor and torque it. Connect the electrical connector. If the slipper head is too far away it will not read a signal. Using you multimeter you can check for voltage, ground, and signal at the sensor Pin A of the sensor connector should be 12.5V+/_1V(this is not batt voltage, it is generated and controlled by the ecm), Pin B is the common(ground), and Pin C is signal. With the key on measure from pin A to pin B: result should be 12.5 volts+/- 1 V. OK? next measure from pin B to pin C(using the DC scale capable of more than 20V). With the key on/not cranking the voltage should be less than 2V or more than 10V, while cranking the voltage should be between 2V and 9V. If adjusting the sensor, and these checks come out ok. You will now need to get into the ecm connector. If we get to this point things can be confusing with out a pin-out diagram and wiring schematic. I tried to copy and paste them to this but it does not appear to be working. You can send me a pm, I will print them and fax it to you if you like. Good luck Quote Link to comment Share on other sites More sharing options...
LARRY BRUDZYNSKI Posted January 30, 2010 Share Posted January 30, 2010 I was waiting for Dirk to jump in on the Cat problems. The other issue I have is the grounds for the engine and the Truck. To much shit has been played with on this truck by the way you are stating it. Backup take a breath and start again.... Quote Link to comment Share on other sites More sharing options...
snw blue by you Posted February 1, 2010 Author Share Posted February 1, 2010 Hey guys. As an update, a new CMP sensor got the engine started and running. Like I said, I was not the one doing the repair so I did not know all the details. What I did know is that the truck drove into the shop. Upon initial reassembly, the timing was off. Seems the kid working on it tried to shortcut the job. He then had the pleasure of taking everything apart and doing it again, this time correctly. That is when he got the crank no start. Checking on Google for this concern and posting here, I learned that the CMP is pretty much in control of fuel delivery etc, I gave my .02 but a few other guys dicked around with it for 2 more days before finally coming to the conclusion the the CMP circuit was where the problem was. How it was determined that it was the sensor, I do not know but it got one and now all is right with the world, well maybe not but I'm sure you get the point. Thanks for the help Quote Link to comment Share on other sites More sharing options...
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