CPS/CAMP Sensor Diagnostics

Lethalthreat7.3 · Apr 1, 2015

Still working on vid. First time with Tapatalk and it won't let me load from my ipad.

TyCorr · Apr 2, 2015

Got it. No worries man. I know the video will show what you are talking about but you explained everything so well already. My wipers are starting to cause noise through the radio now.

lincolnlocker · Apr 2, 2015

is cruise part of the mfs? i have noticed on the dually that the cruise can be finicky and the wipers have gone spastic before too...

live life full throttle

TyCorr · Apr 2, 2015

Jake, sometimes when its really cold out my wipers wont even work when you turn the switch. And the blinkers. Only when real cold. Hopefully cleaning it will remedy this crap.

I swear parking my truck three years ago was the worst thing I ever did to it. Everything stopped working.

lincolnlocker · Apr 2, 2015

TyCorr said:
I swear parking my truck three years ago was the worst thing I ever did to it. Everything stopped working.

yes it is

live life full throttle

gnxtc2 · Apr 2, 2015

Does this apply to an OBS? Also, did you try isolating the injector wires from the rest of the harness?

Billy T.
[email protected]

jeremiahmercier · Apr 2, 2015

Subscribed

Lethalthreat7.3 · Apr 3, 2015

If you are having any issues with the MFS, wipers, signals or hazards(hazards are what seemed to act up first, had to cycle a couple of times for awhile to work), i'd definately look at replacing or cleaning it. Cleaning it is easy just take your time and don't "scratch/pitt" the circuits(fine or ex fine wet/dry works best).

I have not built a inj harness, yet. Waiting to see what others have for results.

Between the '87 YJ I've built for my wife and Elk playing "bumper cars" with my truck(picked up '06 for parts, reason I know their wiper motor uses a mag pickup), and deciding to finally attack the "phantom" issue, i've been staying busy.

Have to finish the carb repair on my son's 900. Finish rebuilding the head on my 1100.

Building the harness is a little more involved than shielded wires from point A to B. it has to be "shunted" in series so it is going to take a little bit. If I had an old IDM to 42pin as well as the engine harness side I'd be in business as I would just build and swap. The primary connectors I need are the IDM and the two injector harness connections if anyone has an old harness(doesn't matter if it has been "chaffed" in between as long as the first 6"-10" at the iDM and inj harness connections are intact)

ja_cain · Apr 4, 2015

Do you think this might be a ground loop issue? When you say a series shunt on the injector signal from the IDM I'm not following you. I use LC circuits on dc control circuits to eliminate noise from say a vfd drive (along with twisted pair shielded control wire). I guess I just don't know enough about the signal you are trying to clean up or suppress or whatever. Isn't the signal from the IDM a step function (to ~110 volts) followed by some oscillating DC waveform?

*edit*
I've got a Rigol scope and would love to build an injector breakout box so I can look at the wave forms. If you end up doing this, please post up some screenshots.

ja_cain · Apr 4, 2015

That meant to read that I use them on the VFD's to reduce harmonics being transmitted to dc control wires and other low voltage signals like thermocouples. Not on the control wires themselves.

OBS-Addiction97 · Apr 4, 2015

Most of what I'm reading in this thread is Greek to me LOL. I'm eager to see the results though.

Lethalthreat7.3 · Apr 5, 2015

Ja cain I understand what you are talking about on the vfd's, used to have any issue with Infinity drives.

I am referring to the "back-flash" transient surge that is created when a magnetic field collapses. The IDM is designed to absorb these but over time from vibration, corrosion, component age as well as design, well the system can have issues.

Think about it like this.
The injectors are AC driven to energize, "magnetize", the solenoids. When the pulse is stopped the magnetic field collapses and there is a sudden very quick surge. This "back-flash" has been seen as high as 1000vac which is "absorbed" by the IDM.

Why do we shunt at a component? To absorb any EMI or RFI that may be created so that it does not "travel" along the wiring.
Now if you happen to have a shielding or surge issue to/from the injectors it must be absorbed by the IDM but the distance from the injector banks to the IDM itself along with the 42pin connection and running parallel along all the DC sensors, well you can create an "antenna amplified" effect. This is why shielded wiring is only grounded at one end(otherwise you create an antenna).

The idea is to absorb any transient surge, EMI and RFI that is produced. I've done some more "suppression" modifications at the uvch connections using extremely strong ceramic magnets to create a "boxed magnetic field" to run just the AC injector wires thru. Although I haven't looked at it with a scope, it is definitely noticeable in how smooth the engine runs and it has cleaned up the "noise" on the LCD of my monitor.

I'll be working on building a different type injector harness over the next week or so as I found some old IDM/Inj connectors in my stuff(junk as my wife would say). I am on a mission now to build a harness specifically to address this.

Still curious as to wether anyone has tried the ground issue/wiper motor/MFS circuit repair or replacement and the results.

ja_cain · Apr 5, 2015

Lethalthreat7.3 said:
Ja cain I understand what you are talking about on the vfd's, used to have any issue with Infinity drives.

I am referring to the "back-flash" transient surge that is created when a magnetic field collapses. The IDM is designed to absorb these but over time from vibration, corrosion, component age as well as design, well the system can have issues.

Think about it like this.
The injectors are AC driven to energize, "magnetize", the solenoids. When the pulse is stopped the magnetic field collapses and there is a sudden very quick surge. This "back-flash" has been seen as high as 1000vac which is "absorbed" by the IDM.

Why do we shunt at a component? To absorb any EMI or RFI that may be created so that it does not "travel" along the wiring.
Now if you happen to have a shielding or surge issue to/from the injectors it must be absorbed by the IDM but the distance from the injector banks to the IDM itself along with the 42pin connection and running parallel along all the DC sensors, well you can create an "antenna amplified" effect. This is why shielded wiring is only grounded at one end(otherwise you create an antenna).

The idea is to absorb any transient surge, EMI and RFI that is produced. I've done some more "suppression" modifications at the uvch connections using extremely strong ceramic magnets to create a "boxed magnetic field" to run just the AC injector wires thru. Although I haven't looked at it with a scope, it is definitely noticeable in how smooth the engine runs and it has cleaned up the "noise" on the LCD of my monitor.

I'll be working on building a different type injector harness over the next week or so as I found some old IDM/Inj connectors in my stuff(junk as my wife would say). I am on a mission now to build a harness specifically to address this.

Still curious as to wether anyone has tried the ground issue/wiper motor/MFS circuit repair or replacement and the results.

Good stuff and thanks for the explanation. That makes sense about the coil/back-flash explanation. Parallel runs are a no-no without separate conduit or twisted pair and shielding. I always try to cross at 90 degrees to limit coupling.

What type of shielded cable you plan on running. I've found for vfd's, the symmetrical drain braided seams pretty good but I don't have a whole lot of experience with vfd's.

silverpsd_06 · Apr 5, 2015

In for video's I like the old clanking of the 7.3 but it'd be nice to run smooth

Dave7.3 · Apr 11, 2015

Any updates?

TyCorr · Apr 12, 2015

silverpsd_06 said:
In for video's I like the old clanking of the 7.3 but it'd be nice to run smooth

I don't remember mine running this rattly and shti until after 150k miles. And its been harder the kast five years to keep things up as aftermarket support is in the toilet even at an oem dealer.

mandkole · Apr 13, 2015

I have to agree with Ty-- as a mfgr of OEM truck parts (not electronic ones), your business model greatly changes on older legacy platforms. The will-fitters are out in force now. In some product areas, these changes are low risk, but in others its critical to product performance and safety.

We have a pretty good handle on the mechanical engine parts, but electronic stuff not so much. As we've found out, the inconsistent quality/performance of sensors and the lack of availability of wiring harnesses, etc. are greatly affecting our efforts to make these engines run like they did from the factory. Nothing worse than starting it and the truck runs perfect, the next start, like crap. This is going to continue to get worse before it gets better.. there is a strong population of 7.3s out there to justify someone getting into the electronics, but it will take time to get the investments made.

TyCorr · Apr 13, 2015

I thought about making cam sensors and after a minimal amount of footwork I brought it up to the guy who works on my truck when I cant and he said he stopped right where I did too.

I don't have the money to do something like that now and if I had tons of $$ id pay someone else to worry.

Id like ten original delphi cps. And a new engine harness. Id be happy.

lincolnlocker · Apr 13, 2015

Lethalthreat7.3 said:
If you are having any issues with the MFS, wipers, signals or hazards(hazards are what seemed to act up first, had to cycle a couple of times for awhile to work), i'd definately look at replacing or cleaning it. Cleaning it is easy just take your time and don't "scratch/pitt" the circuits(fine or ex fine wet/dry works best).

I have not built a inj harness, yet. Waiting to see what others have for results.

Between the '87 YJ I've built for my wife and Elk playing "bumper cars" with my truck(picked up '06 for parts, reason I know their wiper motor uses a mag pickup), and deciding to finally attack the "phantom" issue, i've been staying busy.

Have to finish the carb repair on my son's 900. Finish rebuilding the head on my 1100.

Building the harness is a little more involved than shielded wires from point A to B. it has to be "shunted" in series so it is going to take a little bit. If I had an old IDM to 42pin as well as the engine harness side I'd be in business as I would just build and swap. The primary connectors I need are the IDM and the two injector harness connections if anyone has an old harness(doesn't matter if it has been "chaffed" in between as long as the first 6"-10" at the iDM and inj harness connections are intact)

*** all that. id call painless and tell them what you want! lol

live life full throttle

lincolnlocker · Apr 13, 2015

TyCorr said:
I thought about making cam sensors and after a minimal amount of footwork I brought it up to the guy who works on my truck when I cant and he said he stopped right where I did too.

I don't have the money to do something like that now and if I had tons of $$ id pay someone else to worry.

Id like ten original delphi cps. And a new engine harness. Id be happy.

i have 8 of those cps's... hehe

live life full throttle