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engine dies - throws codes - what do they mean?

I put the tranny in gear and turned key to start - heard the lift pump. The added relay was wired the same as in the thread here with the exception of getting power from the post on the underhood fuse/relay box instead of from the wire going to the OPS. The OPS's gray was cut with both ends terminating in the relay.

No bio or wvo. Just diesel #2 & Diesel Kleen.

TDCO is -0.79
IP Timing fluctuated between 16 and 20.
 
The idle injection timing is way high for idle, is that the measured injection timing?
Or is that the actual IP timing, in which case its low.

Maybe your stepper motor isnt seated correctly.

For the OPS relay, the grey wire from the OPS to the relay should go to contact 85. Contact 86 should go to ground. The grey wire that goes to LP and the power source go to 87 and 30.
 
Oops! Sorry Buddy, I looked at the wrong measurement on GMTDScan.

Just went out there and ran it again. These are my readings:

Idle engine temp @ 170*:
Actual IP timing: 39
Injection timing - measured: 16.9
Injection timing - Desired: 16.5

Driving mostly around 25mph up to 40mph engine temp @ 187*-190*:
Actual IP timing: 37-42
Injection timing - measured: in the 16s
Injection timing - Desired: in the 16s

Do those readings look OK?

The good thing though is I didn't throw any codes today and no stumbling. :thumbsup:

The only thing I've done between last night when I threw codes and today when I didn't is I unplugged the extension for my Heath FSD and plugged in the old FSD which is still mounted on a heatsink attached to the manifold. I could not even get it started hooked up to that. So plugged my Heath back in. I also used a wire brush on the blades of the crank fuse in the dash and the ECM fuse under the hood. And I reattached a ground strap that is part of the wiring going to the hood light (the ground strap has been broke since I got the truck over a year ago).

My test drive today was the same I did last night (maybe a mile) with punching it at the same places, except today after I got back home with no codes I took another longer drive and punched it more. So maybe the fuses weren't making the best contact or maybe an electrical gremlin in the FSD wiring that cleared out after moving it?
 
Factory timing is 3.5* act. and 3.5* des. I have mine set to 8.5* act and 8.5* des. with a TDCO of -1.5* Your numbers are high, what is your TDCO? (edit: found your TDCO in a previous post)

Leo
 
Anything over 8.8 is considered High, You could try rotating the pump 1mm to the passenger side, then to a time set then a relearn and see what you come up with. Maybe even try time set first and see if anything changes.

Leo
 
Does my high number indicate something is worn/broken or getting ready to?

To do a timeset and relearn, I'll need the full version of GMTDScan, correct?
 
It could be the signal ScanTech is reading is false, I think it would run rough with that much advance. Some one else will have to chime in.
Yes you need the full version of ScanTech to set time and TDCO.

Leo
 
Since the TDCO is fine I dont know how you have such high advance, which is why I said maybe stepper motor which controls advance is not seated correct.

It certainly can idle advanced that high. When mine is cold it will go to 13 and slowly come back to 8.5.

The timing is as the EPROM commands, so different chips will have different timing. Are you using the stock PCM and EPROM?
 
I'm not sure if they are stock or not. I've only had the truck for just over a year. The previous owner had some work done. He told me about 4 or 5 things he did, but didn't mention a new chip or reprogramming. He did say he had the shop turn up the boost a couple pounds - would that require a new PCM or eprom?

One other thing to mention: took another short drive in it tonight and ran fine with no codes, but it was very hard to start. Never had a starting problem before. It always used to take a couple seconds or less to fire. Tonight & this afternoon, I cranked for about 5-6 seconds, waited 15-20 seconds, cranked 5-6 seconds, waited another 15-20, then cranked for a few seconds before it fired up. When it was cranking it didn't even act like it was going to fire up.
 
Do you have all dash lights when it wouldn't start? Perhaps the cycling of the key is what made it start that last time while the first times it sounded as if it didn't want to start. Suspect Ignition switch?
 
I had all the dash lights each time including WTS. It acted like it was getting fuel - just kept cranking with no hint of firing.
 
huh, I went back to your checklist and realized you had an extra code in there not in the original list.

DTC 19, Crank Position Sensor. And you have 18, Optical Sensor Cam reference. Those are the two timing references. If neither is functioning then you wont get any fuel flow command from PCM. So the truck will just crank no sign of turning over. May also explain why idle timing is so messed up, because the timing references are compromised. Maybe its in limp mode. Do you still get DTC19?

Have you unplugged either CPS or OS at all?
 
I've not unplugged CPS or OS.

I don't know what the deal is, but it is running great today. Started right up. Took it on a 10 minute drive and mashed it to the floor several times - no stumble, no codes. Actual IP timing was between 37-41 while driving - about 38 idling in the driveway when I got back (ECT at 188*), and injection timing still in the 16s.

Maybe I had some junk in my fuel and it finally cleared out? I dunno - this truck is my only experience with a diesel, and even though I've learned a lot on this forum, there still is a ton for me to learn.

Anyway, thanks to all for the help - even if I haven't figured out exactly what the problem was, you guys helped me from spending a ton of money on replacing parts. Dinner is on me if our paths cross.
 
OK, nevermind on the previous post. Just loaded up the kids to head to Dairy Queen and it died backing out of the drive. Started right up, put in R, started moving and it died. Started right back up, put in R, backed on the street, put in D, and it died. Started right back up and pulled back in the drive, put in P, it idled for a few seconds then died. Started back up, popped the hood, opened the T-valve, got fuel just as it died. Started back up, opened the valve, fuel started streaming & it kept running, closed the valve, a few seconds later it died. No SES light.

So what does unplugging CPS & OS do and should I try that?
 
Do you have stored codes now? Have you cleared the codes since last checked?

The truck needs one or the other working to run, those are the PCMs only timing references. It should start if you unplug one or the other. Sometimes unplugging the OS will help get it started. Although it may take several seconds of cranking. It would then run in backup/limp fuel mode.

Have you determined if your LP is working? Do you know to check pin G for battery voltage, 14V, at pin G of the OBD1 port when truck is running? That will tell you if OPS is sending voltage to LP. With truck off, put tranny in gear and turn IGN to START (it should not crank) and is LP running, fuel coming out of drain line?
 
I cleared the codes before each test drive.

Currently, I have 18-Pump cam reference pulse error in Historic codes. I haven't started the truck since Saturday evening.

Trying to start right now, tried twice cranking for about 5-6 seconds. Running on third attempt.

While running, no voltage at pin G, but I can feel the LP working.

When not running with truck in gear and key to start, I hear LP working and get fuel at the drain line.

Not sure if this helps, but at idle, injection pulse width is 1.86 - held it at 2,000 rpm for a few seconds and injection pulse width was 1.9.

Just took in for a 3 mile drive after it warmed up, punched it a few times, no codes.

Readings now with it warmed up and after the drive, tranny in Park:

Actual injection pump timing: fluctuating between 38.19 - 39.5
Injection timing - measured: 16.4-16.8
Injection timing - desired: 16.6
Fuel rate (no throttle): 8.12
Fuel rate (rpm held at 2,000): 8.75


Does this sound like maybe a flaky sensor/relay since sometimes I can drive with no codes and then other times it codes and stalls? When it codes, it sometimes has multiple (18, 35, 54), but everytime there are codes, it has 18 (sometimes only 18).
 
Its probably related to your timing being so far advanced. Leads me to the stepper motor still, not sure how you can check if its good, will have to get back with you after work on that.

The injection pulse width shouldnt change much at idle, even with your foot into the pedal, its within tolerance now, although a little high. Can you check the PCM to see if you have an aftermarket EPROM in it? Youll have to pull PCM out from behind glove box and open up the little lid on the back. Then read the code on the EPROM chip and see if any brand names on it. Can do that without unplugging the PCM harnesses.

I would check actual voltage at the LP to see if youre getting 14V while its running. Has nothing to do with timing, but could contribute to DTC35. DTC54 probably has to do with the timing being off, PCM gets confused on what injection pulse width and fuel rate to command, or stepper motor is not doing what it wants it to.
 
13.78 volts at the LP while running.

Codes on EPROM (if the EPROM is the chip inside the blue plastic housing under the access panel):
BXPW5

014
67633
B0352AD


I didn't see any brand names.
 
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