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Discussion Starter #41
Pikachu - not that I know of. I bought the truck in April of 2008 with 174k miles on it. It has about 198k on it now... and I've never added a tuner or chip.... yet :)

Thanks in advance for your help! I ordered a fuel pressure gauge and that will hopefully be here by the weekend. If the weather in Dallas will cooperate, I'm gonna try and swap the ICP this evening as it does have signs some oil leakage has occurred in the (near) past.

I don't know anyone with a spare PCM... if I took mine out, would the dealer be able to run diagnostics on it without it being in the truck or something? Or the IDM?
 

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No and no. The dealer won't touch it unless it is in the truck and either drove in their bay or towed in. I believe it is the PCM that is bad as if it was the IDM he would be getting the codes that I showed above. It seems like the IDM isn't even getting sent the message to fire. I would look at a junk yard and see if they have one and then you could delete all DTC codes found in it and see if it helps you out as it would be cheaper and quicker than ordering new.
 

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The idm is being told to fire the injectors through the buzz test. The pcm is seeing the cps by seeing rpm too. If he has fuel pressure, i would look at the idm/pcm. Idm is easiest to borrow.

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I would visit the parts store. They usually have an oil pressure setup that will work for $40. It can be hooked up on the passenger fuel rail via the 1/8"npt plug next to the ac compressor

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That isn't an 1/8" NPT thread there; it's #4 female ORB, which is a straight thread whereas pipe thread is tapered. Any halfway decent hydraulics shop should have an adapter from #4 ORB to 1/8" NPT for a couple bucks.
 

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That isn't an 1/8" NPT thread there; it's #4 female ORB, which is a straight thread whereas pipe thread is tapered. Any halfway decent hydraulics shop should have an adapter from #4 ORB to 1/8" NPT for a couple bucks.

Actually - its 1/8 NPT. Its a square head plug in the front of the passenger side head and on the rear of the driver's side head. Its where the fuel line would go if that head were on the opposite side. If you need pictures, look at figures 6 and 8 in this instruction sheet - http://www.riffraffdiesel.com/content/RESOURCES/Riffraff_Diesel_FRx_Instructions.pdf
 

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Actually - its 1/8 NPT. Its a square head plug in the front of the passenger side head and on the rear of the driver's side head. Its where the fuel line would go if that head were on the opposite side. If you need pictures, look at figures 6 and 8 in this instruction sheet - http://www.riffraffdiesel.com/content/RESOURCES/Riffraff_Diesel_FRx_Instructions.pdf
Yes, that's right, my bad. My mind was on the ports on the filter housing; those are #4 ORB. The plugs on the heads are indeed 1/8" NPT.
 

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I don't see anything in the PC/ED to look for that wouldn't throw a code if it was faulty. After looking at the data, I think the ICP sensor is probably reliable, and the IPR is working. The RPM reading is evidence the cam position sensor is working. The fact that the injector pulse width never comes up to a level that would actually allow the engine to start, even though all the other parameters are in spec, makes me think the PCM is the problem. I realize I'm not there to actually see and hear it, and I'd hate to tell anyone to shell out the cash for a PCM and have it not solve the problem. If it was my truck I'd try really hard to find one I could borrow to at least confirm it or possibly rule it out. If I had a spare kicking around, I'd send it off to you to try.
 

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Discussion Starter #49
Pikachu - thanks! I still want to change out the ICP only because I see evidence of oil around where its attached. I'll pull the PCM also... if nothing more than to get the numbers off of it so maybe I can call around to some local yards and see if I can find a replacement to at least test with.
With the PCM out, anything I should look at? Should I open it up, look for a chip or scorch marks or anything?

Any particular good places/vendors to look at for a known good replacement?
 

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If there's been a chip installed, you'll probably find the plug missing from the back end of the PCM when you slide it out of the bracket. Opening it up probably won't reveal anything, but if you determine it's bad and want to see what the inside of one looks like, go for it!

There are a few companies that test and repair PCMs but I can't think of their names off the top of my head.
 

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Discussion Starter #51
Wow. I went ahead and pulled the PCM, and after I unplugged it and trying to get it out of the truck, I can hear that something is loose inside it. So I finally get it out of the truck and slide it out of the black plastic "cage". The plug is gone, but nothing plugged in to the circuit board. As I move the case around I can hear something metallic moving around in there... so I tip it so the plug opening is down and out slides... a razor blade. No sh!t.

I open the PCM, and everything looks fine (to me) except the back side of the board, down by the connector which looks discolored and you can see some areas of the board coating is removed on the connector itself.

I put it back together (without the razor blade), put it back in the truck. No-go. Wishful thinking.

So I still don't know if the PCM is the cause of the no-start, but having a razor blade in there certainly isn't good. Whoever put that in there... WTH were they thinking?

So my PCM is PMT2. Looking online, PCMs look like they're about $500, and I didn't even find many places selling them. I'll try to call local yards tomorrow, too, but... maybe $500 is what it'll take.
 

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Those two pads touching each other is not a good thing. You might try getting them separated and give it a whirl, but I would lean towards them being shorted and frying a chip.

It appears someone tried removing the coating on the board with a beltsander
 

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OMG. Someone really hacked that up badly.
 

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Discussion Starter #54
Quick update... straightened the contacts on that part of the circuit board connector and put the PCM back in, still no-go.
Also swapped the ICP, and no-go either. Didn't put AE on it though so not sure if the ICP values changed at all. Main reason I swapped it was cuz it looked like oil may have been leaking from it...
 

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My guess is that the razor blade hit two points on the PCM while driving and bouncing around in there and shorted out your PCM, but that doesn't exactly make sense to me as if it had shorted then you wouldn't even be able to talk to the PCM and pull codes. I hate electronics and I'm still saying for you to try and find a used one to test. Last time I checked you could pick up a PCM at the junk yard for about $60
 

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Discussion Starter #56
Got another PCM today (PMT1 vs original PMT2)... and no-go. Going to hook up the AE to it to see if get anything different.
Also bought the IDM off the same truck the PCM came from, so will try that next I guess...
 

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Well, that isn't what I was hoping to hear. Especially after seeing what the other PCM looked like . . .
 

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Discussion Starter #58
Well, good news. Replaced the IDM at she fired right up. So amazingly, the F'd up PCM with a razor blade inside wasn't it, but I've decided to keep the one I bought today installed in the truck. Will keep the original around for testing if ever needed.

Here's something weird though. AE still reports pulse width is between 0.28 and 0.30. So either AE is displaying it wrong (and it should be 2.8 or something), or "Fuel Injector Pulse Width" isn't what I thought it was. :)

Haven't taken it for a drive yet, but started it multiple times and let it idle for a bit. Also ran a KOEO and a KOER test and the only code to come back was for the intake heater (which I don't have, so not surprised).

Thanks to everyone who helped with this! I've learned quite a bit... which usually happens in instances like this :) You guys rock.

Still weird about the AE pulse width reading though...
 

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Excellent! Most everyone I've know who has put a PMT1 PCM in their truck has liked the shift strategy better than the PCM it replaced, so that might at least make this whole ordeal a little easier to stomach.
 

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Well, good news. Replaced the IDM at she fired right up. So amazingly, the F'd up PCM with a razor blade inside wasn't it, but I've decided to keep the one I bought today installed in the truck. Will keep the original around for testing if ever needed.

Here's something weird though. AE still reports pulse width is between 0.28 and 0.30. So either AE is displaying it wrong (and it should be 2.8 or something), or "Fuel Injector Pulse Width" isn't what I thought it was. :)

Haven't taken it for a drive yet, but started it multiple times and let it idle for a bit. Also ran a KOEO and a KOER test and the only code to come back was for the intake heater (which I don't have, so not surprised).

Thanks to everyone who helped with this! I've learned quite a bit... which usually happens in instances like this :) You guys rock.

Still weird about the AE pulse width reading though...


Did you try reinstalling your original PCM ?

Might not want to just in case it's F'd and shorted out your original IDM.
 
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