sethreesh

Loren that’s wild. Sorry it keeps happening to you. On a good note the truck it up and running no more surging!! Thanks for all the advice and patience with me as we figured it out.

I paid 1400. They gave me a military discount and a forum discount. They also did the PCM and ECM harness. The work they did was really good. Not one drop of oil or residue. Even smells clean. All the insulation and wrap is new and tight. I was hesitant at first but am very happy.

I shouldn’t laugh but that is humorous

Got my harnesses back. @Auto Computer Specialistdid a bang up jump cleaning them all up. Going to install tomorrow evening or Saturday weather depending. Anything to look out for when I put them back in?

Oh I’m just cleaning up the engine while the loom is out for testing. Like your crank case breather mod I need to do that as that vent has made everything below it absolutely disgusting.

Hey guys while the ECM/PCM/Wiring Harness are at the @Auto Computer Specialist shop I am reviewing the grounds again just to triple check and make sure I have all the major ones. Want to check with you guys to see if I'm missing anything. So far I have cleaned up: Outside The Cab 1. Driver side battery ground to engine just below the power steering pump on the timing case. 2. Driver side battery to frame mount for the front bumper 3. Driver side battery to body on the fender 4. The G100 just behind the driver side head light 5. Additional ground by G100 (two leads going to it; which one is this?) 6. Just aft of the PDC bolted to ABS controller coming out of wiring harness (not sure which one this is to) 7. Passenger side battery to PCM 8. Passenger side battery Engine 9. Passenger side battery to Body 10. Just above starter below ECM 11. W-T mod on timing case Inside The Cab 1. Two sets on driver side kickplate 2. Centerline in dash frame below radio Let me know what I'm missing. Thanks guys.

So tan/black to battery ground? Just making sure I understand. You’re saying the short could be in that signal causing the error. And it’s probably a small break so it’s intermittent

I'm really interested in where the short is at. The tan/black wire from the ECM to ECT is a brand new pinned in wire. All the sensor grounds tested less than .2 ohms each last night from the ECM plug to the sensor. I sat on the kitchen floor with it all laid out and tested each point. This is driving me. Interesting that I am not getting any codes from this. Only way to get a code is to unplug the sensor. The P1693 was stuck in for a while but when I did the W-T mod that went away. But hey at least I'm not paying diesel prices in WA right now....have to find the bright side.

I did that as my very first step of troubleshooting. Put in a ECT from NAPA still had problems. Did a bunch of other troubleshooting. Thought maybe the NAPA one was bad so I pump in one from Cummins still had problems. With it unplug and multimeter on the ECT sensor you can watch resistance change as temp increases.

Well guys here with an update I got the ECM and PCM out along with both harnesses out. It's currently on route to @Auto Computer Specialist. Should be there this Thursday. Let's hope they are able to figure out this rouge electrical problem. Those harnesses get pretty nasty I pulled all the old brittle plastic insulation off cleaned off all the old tape. The splice looked in good condition but I didn't break into it. For those wondering splice S165 sat just below the power steering pump on my truck. While all that stuff is out for the next few weeks any one have suggestions on what I should do to continue making this baby shine? I have a BHAF sitting waiting to be put in when I put everything else back in for the electrical problems.

Haha you’re telling me looks like I’ll pull it off on Sunday and send it out…

I may just make a entire new ground line that goes from the ECM to each associated sensor to eliminate it from being a problem.

Loren do you know exactly where that is in the loom I have the loom opened up from the ECM to where it begins to dip below the power steering pump and I don’t see it

So a little more digging on the s165 the apps ground, ECT ground, oil pressure ground, cam ground all read at 6 ohms, the IAT ground read at 5 ohms and the pin at the ECM (pin 11) was 5 ohms. The ECT is the only on that seems to change the live value on my scan tool. So it looks like I need to go into the loom and see if I need to repair that connection…

Here’s a live view of the ECT and surging. I’m going to dig into the s165 splice and see what I find The shop I left it at couldn’t figure it out and want to say it’s the ECM I can’t imagine after it being looked at twice by ACS that it’s the ECM

IBMobile how would you test at the splice? You’re talking about the S165 right? That’s the one in from of the ECM just behind the injection pump? With the ECT unplugged the truck runs perfect. It has 5V constant at the tan/black wire at the ECT sensor plug.

Hey guys back with another update. Got the ECM/PCM back again from ACS it’s still surging. The only value that changes with the surging is the ECT. I replaced every wire that comes from the battery. Cleaned all the major grounds. The only sensor I haven’t replaced is the oil pressure sensor. Any more thoughts. The 1693 is completely gone now though. It was still there when I got the computers back but after I replaced the ground wires and completed the WT mod and the PCM ground mod it went away.

PCM installed still surging. I think they missed something with the ECM still on the scanner you can see the ECT open circuit and return to normal. Pulling ECM sand PCM and sending back to ACS for them to look at.

Hey guys in with a update. I traced and replaced every possible bad wire in the harness. Cleaned it up a lot. Still surging. Pulled the PCM and sent it off. They just got back with me they replaced 3 blown capacitors. It’s in the mail on the way back fingers crossed.

LorenS On a live data the IAT is showing no indication of failure during the surging. On the graph you will see the ECT go low while nothing else changes. However with the ECT sensor unplugged the surging stays present. You’ll get the hi voltage error code that way though. IBMobile The sensor was replaced. With a multimeter the resistance tracks as it should with a change in temperature. I almost think there is a short to ground somewhere interrupting communication causing it to load up on fuel. I just don’t know where. I know the ECM, PCM, and data link all eventually tie in together at a ground. Maybe it’s the common ground splice under the air box or there is a wire that is rubbing that the vibrations of the engine running make it contact and short then regain signal. I know the ECT is recieving the 5V signal. And the 5V wire was replace from the ECM to the ECT it’s currently out of the harness loom as a standalone. Still the only error code I get is the companion 1693…

Hey guys I'm back from deployment. My wife sent in the ECM to get looked at by auto-computer specialist. Still having issues. They had me replace the crank and cam sensors prior to reinstalling the ECM. The dash cluster is showing that the engine is cold running and when you plug in a DTC to the OBDII port it reads -40 but will occasionally flash to about 180-190. I have had the ECM rebuilt by autocomputer specialist and they sent it back with some repairs done. I have replaced the injection pump, upgraded the fuel pump to a FASS, replaced the APPS with a TIMBO, cleaned up alot of the wiring, new alternator, new batteries. Do you think I could have a short in the same problem causing the PCM to send that it's -40 and the ECM sends a bunch of extra fuel causing the surge. When the gage cluster is reading the right ECT the surging goes away. When the ECT tanks out or doesn't respond at all the surging stays present? Please let me know your thoughts. I sent the truck down to the local mechanic shop they seem to be stratching their heads too. But I was trying to save some of my own time as my ship is now in port at the shipyard up here in Washington and I'm spending most of my days wrenching on a submarine instead.

I deploy tomorrow. I'm gonna pull the ECM out and have the wife send it for testing and coordinating that. Who do you recommend I send it too.

What's your recommendation for my next step forward? Im going to put everything back together and run it and see what it does later today. Weird thing is if I unplug the sensor the p0118 comes on. But if it's plugged in it reads 293 now. I'm getting 5v on the sensing wire. 0.2 volts on the ground wire. And the resistance on the sensor is about 19k cold. It's in the low 50s.

Replaced the wire. Now the truck reads 293 on the scan to with the key in the on position. I'm assuming the ECM is bad at this point.

Did the wire test between the ECT/ECM. I had 0.16 ohms for both the sensing signal wire (tan/black/#14) and the ground wire (blue/black#13). However there is some bare open wire on the tan/black wire right as it goes into the plug. Any advice on how to change out that wire. I've never done that before.