sudden RPM fluctuations in an '03
#16
very knowledgeable and generous help here. Much appreciated. My problem is clear now. My challenge is time and the lack of tools at the moment, so I'm going to submit to my trusted mechanic for a new ICP and pigtail while he's in there. (just getting the pigtail to wiggle was an exercise in painful hand contortions so i'm imagining that swapping the things will take more than I have right now.)
o4badford, sounds like you new to start up a pigtail overhaul operation. I'll be your first customer.
Hoping this keeps me running for a while now.
Thanks again!
o4badford, sounds like you new to start up a pigtail overhaul operation. I'll be your first customer.
Hoping this keeps me running for a while now.
Thanks again!
#17
Hey if we were a little closer you bet I would help ya, the early built ICP thing is a beach just because it's under the frigin Turbo , the actual replacement is not so bad just have to move a few thing out the way, skin it. Laying across the side down in the ( hole ) gets a little tiring , Good luck and keep us posted on the Out come
#18
Bringing back an old thread as my problem has reared its ugly head again. TRuck will run beautifully for months, then goes to he11 intermittently, and sometimes fixes itself.
SUMMARY:
- abrupt RPM fluctuations while under load (accelerating), sometimes stalls suddenly
- had some great advice here to switch to Synthetic (Done), replace ICP (Done), check pigtail (Done)
- Ive brought it to my mechanic several times for this problem and now he's stumped too (he changed the ICP a few months back, certified the pigtail to be like new, tested FICM volts (normal IN and OUT), tested fuel pressure (norm), re-tested ICP volts (desired and actual were same), tried disconnecting ICP again (made no difference), swapped PCM (no change)
- he suggested next step to try swapping FICM, but I said to hold off until I do some research here. Hoping to not throw expensive darts.
- we discussed that maybe it was a tank of bad fuel as this episode roughly coincided with a fill up. I'm doubtful though.
- here's the codes that he saw. I'll post a couple quick videos after this.
SUMMARY:
- abrupt RPM fluctuations while under load (accelerating), sometimes stalls suddenly
- had some great advice here to switch to Synthetic (Done), replace ICP (Done), check pigtail (Done)
- Ive brought it to my mechanic several times for this problem and now he's stumped too (he changed the ICP a few months back, certified the pigtail to be like new, tested FICM volts (normal IN and OUT), tested fuel pressure (norm), re-tested ICP volts (desired and actual were same), tried disconnecting ICP again (made no difference), swapped PCM (no change)
- he suggested next step to try swapping FICM, but I said to hold off until I do some research here. Hoping to not throw expensive darts.
- we discussed that maybe it was a tank of bad fuel as this episode roughly coincided with a fill up. I'm doubtful though.
- here's the codes that he saw. I'll post a couple quick videos after this.
#19
336 is cam shaft sensor
341 is crank shaft sensor
Both of them should be a 1 for sync... and they will kill a motor like turning the key off. This is something you can see using your scan gauge, just need to program the X-Gauge for it. Should go from a 0-1 when cranking.
403 & 405 are EGR related, makes the turbo possible slow to come up. Make sure its plugged in and the wires are not shorted at the plug... not your issue.
672 & 678 are Glow plug fault on #2 & #8, change the harness and the plugs on the drivers side. This would be a starting issue when cold, plug the truck in to help it... not your issue.
P1000 is an incomplete self test, don't sweat that one, with run time will clear itself.
P2614/2617 are cam/crank codes again. You may have bad sensors or the harness for those is chaffed... wiggle the wires for both and see what you get. Watch the scan gauge again for this. One code for cam, one for crank, both should go to 1 when cranking.
p0148
read this thread, they are talking about the same code... maybe related to the cam/crank sensors.
Hope this helps
Bad fuel, normally a filter change and an additive to help... not that, it would run crappy all the time.
FICM voltages should be above 45v for output and input above 10.5v, best input is 12v since it's a step up transformer. What are FICM voltage at when cranking and once fully warm?
Whats fuel pressure at?
341 is crank shaft sensor
Both of them should be a 1 for sync... and they will kill a motor like turning the key off. This is something you can see using your scan gauge, just need to program the X-Gauge for it. Should go from a 0-1 when cranking.
403 & 405 are EGR related, makes the turbo possible slow to come up. Make sure its plugged in and the wires are not shorted at the plug... not your issue.
672 & 678 are Glow plug fault on #2 & #8, change the harness and the plugs on the drivers side. This would be a starting issue when cold, plug the truck in to help it... not your issue.
P1000 is an incomplete self test, don't sweat that one, with run time will clear itself.
P2614/2617 are cam/crank codes again. You may have bad sensors or the harness for those is chaffed... wiggle the wires for both and see what you get. Watch the scan gauge again for this. One code for cam, one for crank, both should go to 1 when cranking.
p0148
read this thread, they are talking about the same code... maybe related to the cam/crank sensors.
Hope this helps
Bad fuel, normally a filter change and an additive to help... not that, it would run crappy all the time.
FICM voltages should be above 45v for output and input above 10.5v, best input is 12v since it's a step up transformer. What are FICM voltage at when cranking and once fully warm?
Whats fuel pressure at?
#22
#24
#26
#27
#28
Ie 0=not in sync.... correct. It should go from a 0 with KOEO to a 1 as soon as you crank it... if they function correctly. Watching the video, you have a solid ZERO. May have the wrong x-gauge information programmed for that PID... it would have not started at a 0. There is also one for FICM sync.
You need cam/crank/FICM sync to start.
What happens to the readings when its goes crazy?
ICP, FMP, ICPV are good, that SYC is suspect.
That's no good, unplugging the EGR makes the fan not work properly... it controls fan speed, not just EGR exhaust flow. Wonder if the plug has some shorted wire in it... I would check that carefully, looks like a chewed up mess!
You need cam/crank/FICM sync to start.
What happens to the readings when its goes crazy?
ICP, FMP, ICPV are good, that SYC is suspect.
That's no good, unplugging the EGR makes the fan not work properly... it controls fan speed, not just EGR exhaust flow. Wonder if the plug has some shorted wire in it... I would check that carefully, looks like a chewed up mess!
#30
Well, I cleaned up that EGR plug and reattached it and it started up smooth as silk! Revved up nice too.
Then I fiddled with scan gauge as I'd found a different digit for FICM logic power and when starting it up again, it let out a burp, and it's back to usual. Maybe worse.
This reminds me of a few months ago when truck had been running perfectly and upon starting, it let out the same burp (just like an abrupt RPM spike, with some blue smoke) and then ran like crap until mechanic unplugged EGR.
I also double checked the 'camshaft and crankshaft in sync' code (SYC) and it's correct, but as you say, stuck at zero.
Programmed and double checked FICM logic power (FLP) and it remains blank. (With 2 different variations of SGII code)
Anyone have better FLP and SYC codes for my early '03?
Thanks again for the advice so far
This just at idle now.
Then I fiddled with scan gauge as I'd found a different digit for FICM logic power and when starting it up again, it let out a burp, and it's back to usual. Maybe worse.
This reminds me of a few months ago when truck had been running perfectly and upon starting, it let out the same burp (just like an abrupt RPM spike, with some blue smoke) and then ran like crap until mechanic unplugged EGR.
I also double checked the 'camshaft and crankshaft in sync' code (SYC) and it's correct, but as you say, stuck at zero.
Programmed and double checked FICM logic power (FLP) and it remains blank. (With 2 different variations of SGII code)
Anyone have better FLP and SYC codes for my early '03?
Thanks again for the advice so far
This just at idle now.