BTW, where are the PCM and IDM located? Thanks

 

PCM= behind the e-brake assy/ firewall
IDM= drivers side fender right behind airbox




can we please recap this post. these long posts make my head hurt....

does truck start sometimes?
getting any white smoke?
full of diesel?
does fuel bowl got diesel in it??
tach moving while cranking?
cold where you live????
is your gp system up to snuff????
batteries charged???
ipr tin nut loose?
have you tried plugging it in for a couple of hours?
got a chip or programmer?
have you removed it?
got any blown fuses?
that should keep you busy....
please copy this and post answers
i.e. do you hate your truck right now? yes


btw those codes unless pcm was cleared could be old.

 

NMRancher, had another thought on your problem. If I've read this right, the truck started fine after you've loosened or removed (and retightened/replaced) the fuel filter canister cover. Is this something you can duplicate? That would lead me to think it's a problem with the FPR (fuel pressure regulator). I know you've cleaned the screen, but there's internal springs and such that may be sticking. I beleive there's a rebuild kit available but I'd have to do a search for the part number(s). Just a thought.

 

Yeah, I see where you are going w/ this, and I cleaned the FPR after that incident so I was thinking the same thing. I already have the PN for the kit written down.


But it has started at least 2 dozen times after all manner of "yes I touched that, but no I didn't touch that" scenarios (and failed to restart each time).

 

Good idea 97.

Recap:

- Truck starts sometimes, I'd say a random 5% chance it will start any given time, and 95% of the time fails to restart.
- No white smoke.
- Diesel in both tanks, switch toggled to each w/ no noticed diff.
- Diesel in bowl, 45psi under normal cranking at schraeder.
- Tach is moving, it is going to be 60 degrees today.
- GPR is working, I didn't test the GPs however.
- Batteries charged, even replaced one.
- IPR tin nut? What is that? I cleaned the FPR and have good presure.
- One incidence of blown fuses, #4, 5, & 7 I believe, smaller fuses, related to the heater because both wires were dead, replaced the fuses and both wires were hot. I disconnected both heater wires. And it started, making me thing I'd found something. Not.
- Have not plugged it in becasue I don't believe that is the issue. I've never plugged this truck in, not even sure if it has a block heater.
- No chip or other performance nonsen, err, stuff.
- No codes w/ Innova ODBII scanner.
- All dealers are the spawn of satan.


Hope this covers it.

 

IPR tin nut: If this refers to the weird looking harness on the IPR, it looks tight, I checked all the connections there, although the IPR is kinda buried.


Let's talk about the IPR then as a source of this problem. Recall that I couldn't find any voltage (other than for the GPs) at the valve covers, under cranking. So, if the IPR isn't functioning, wouldn't it be the case that the IDM would still open the injector, but there would be little or no pressure, and the injector may not deliver fuel (or enough fuel).

Of course, I'm not convinced my test unit is working, but why wouldn't it?

 

try plugging in your truck....look by the oil cooler/filter for the orange cord follow it out.
i'm no expert but it sounds like to me everything is good and you have a gp system problem.

when your truck starts does it stay running normal or does it die?

 

Starts & runs fine.

Now, there was one occasion, I think on page 2, where it fired up, ran for 2 seconds, then died. But fired right back up. It did this probably 5 times in a row, and then started, ran, & drove normal for about a week (I just didn't leave the ranch in it).

Other than those 5 times, it either starts instantly and runs perfectly or will not start at all, no smoke, no nothing. No in-between.

 

Forgot to add I just got done checking the GPs and I have one bad one, cyl #2 I think (d/s front).

Other 7 GPs are in spec, and GPR is operating normally.

At this point nobody is going to convince me this has anything to do w/ the GPs. I'm moving on....

Tomorrow I will check for shorts between the IDM and VC, and try and figure out why I'm not reading any voltage there.

 

i would try replacing the gpr for 23.00 bucks from napa... everything sounds good to me. or you are having a very weird cps issue.

 

I know this may sound weird, but next time it won't start, try unplugging the EBP sensor. It is located at the front of the engine near the top of the water pump pulley. On a few rare occasions, I have seen this sensor cause problems with the PCM's reference voltage circuit, causing the engine to not start.

If all else fails, you may have to take the truck to another shop. Believe it or not, there are some dealership techs out there who can fix more than a ham sandwich. If you lived closer to me, I'd love to help you out. I like a good challenge once in a while.

 

EBP? Exhaust back pressure?? I will try this tomorrow.

I'm sure that the vast majority of techs are pros, and like what they do, and if I had a chance to sit down with one he/she would probably be entertained and challenged by this problem.


I do not blame the techs. My stepbrother is a GM tech, and a hell of a mechanic (but he lives in WA, so he is no help to me).


But basically what happened to me earlier in the week is my mechanical ability or knowledge or whatever, combined w/ this message board, prevented Expressway Ford in El Paso, Texas, from stealing almost $1,000 from me.


They said the CPS was bad. They said the GPR was bad, the said ALL, not some, not one, not a few, not a handful, A-L-L, the GPs were bad.

What do I have? A truck w/ one GP out of spec, a good GPR, a BRAND-FING-NEW CPS, that still won't start. Laziness on the part of the tech, or deliberate attempts to fleece unknowing (oops!) customers, either way when you are talking about nine hundred bucks that is inexcusable regardless of cause. I definitely plan on returning to Expressway Ford once I figure out what is wrong w/ this damn thing. The more I think about what they attempted to do to me the angrier I get.

Just think about how many folks would have surrendered the $900 willingly and w/out question. Most. I always play dumb in this situation, and it always amazes, disappoints, and sometimes enrages me how often repair shops, esp. dealers, will attempt to take advantage of unsuspecting customers. I could tell you stories for hours....

 

You have a GP fixation! )

The GPR is good. Trust me.


The "weird cps issue" has crossed my mind, so after I tested the GPs and GPR I unplugged it and looked at the tach, it didn't move at all. Plugged it back in, and now I have no more doubts about that. I now have 2 brand new batteries and the tach is a bouncin'.

GPR is good, 7 good GPs, cam sensor seems to be working.


No voltage at the VC when cranking.

 

NWRancher, as far as no voltage at the VC when cranking. I'm wondering if the injector signal/pulse is to fast for your digital meter. I work with electronics and occasionally run into a signal that is too fast to register on a digital meter. I carry one of the old analog meters for those occasions, and even then it's difficult to "see" some signals. Just a thought. I think you can get a analog meter at Radio Shack for like $20.00, but it still might not do you any good. The only good way to test the injector circuitry that I'm aware of is to run a buzz test. I believe that not only exercises the injectors, but also should test the wiring since the test is run through the normal wiring/controls.

 

yes sir!!!!!!


a buzz test although testing the injectors, in order for the buzz to work your idm and wiring must work also.


nmrancher....
i dont know what you want to hear...
if it were me i would eliminate the easy stuff first.
my truck although it had a bad gpr... would still start because it was alllowing just enough power to the glow plugs... on warm days it would start right up and on cold would take multiple cycles. if your volt meter doesnt drop to almost "8" after you turn the key on and then hear the "CLICK" you got an issue..
fwiw