LB7: Uhoh....

McRat

McRat

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5.0 on the balance is not perfect, but it's not usually going to do that.

No codes at all?

My guess is going to be a bad regulator or CP3.

Datalog it cruising at 55mph if you can get it up there, and see if the CP3 pressure is constant.
 
TheBac

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uwyo_dmax said:
dang Tom sorry to hear about :( glad to hear you got your trans shifting well.
Click to expand...

Thanks again for your help.

Guys, Ill try those things tonight or tomorrow. Ill look into the diagnostic side of my V1 and see if that command is available. Is it on ver 7.5 or the new one?

Pat, I havent checked it all yet. I get an intakeheater code (for removing it -- I didnt turn it off in my stock tune). Ive got to reinstall it first, then check it all over. I did log rail and it holds, but fluctuates 500psi either way of desired up thru 7500psi..didnt log higher than that. FPR request is a bit higher than desired, but stays steady as throttle increases.
 
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JoshH

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Crazy idea, could it be a lift pump going bad? I don't know what you're running, but if it isn't a flow through, maybe it's causing a restriction?
 
TheBac

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Josh, I run FASS150, and its working perfect.


But I did do some diagnosing this evening and these codes came up:

P0118 Engine Coolant Temperature (ECT) Sensor Circuit High Voltage

and the ubiquitous P1093!

I happened to notice on teh way home that my temp gauge never registered anything. It stayed at 160. I figured, "great, the stepper motor went out, too". But this morning, the gauge was working again, and the truck was running better than it did yesterday. About 8 miles from work, the gauge just dropped to 160 again, and I heard loud diesel "clatter" and the truck started bucking and snorting again. Idle was all over the map, from 600 to 1200, surging badly. This evening, gauge worked fine until I got off the freeway, then all hell broke loose. Gauge started dancing from 160-210, and the idle speed (I was stopped at red light) was following right along! The dieseling was back, too.

So my theory is thus: the ecm reads coolant temp to help figure fuel quantities and timing, right? If the sensor starts to go bad and starts reading like its 0* outside, the fuel tables and timing goes into "cold temp" mode...right? Combine that with the conflicting info coming from the IAT sensor (it would be reading hotter intake temps), and the ecm gets confused...and goes into protection mode. Since Im at 100% throttle when this happens, it triggers the 1093.

Per alldata: ENGINE COOLANT TEMPERATURE GAGE
The IPC displays the engine coolant temperature as determined by the PCM. The IPC receives a class 2 message from the PCM indicating the engine coolant temperature. The engine coolant temperature gage defaults to 75°C (160°F) or below when:

* The PCM detects a malfunction in the engine coolant temperature sensor circuit.
* The IPC detects a loss of class 2 communication with the PCM





Opinions?
 
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TheBac

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Pat, the one thing we noticed at the track was that the problem stayed with either the race tune or the stock tune loaded. What should I look at in the race tune to see if what you're talking about is still active?

I bought a new sensor tonight. Heck, it was only $20. Will change it out and see what happens. From what I read on Alldata, the 03's only have one sensor. Is that correct?

On EDIT: Oh, forgot to add that when I was poking around under the truck tonight, I notice my DS motor mount has a nice long crack thru it. So I get to replace that, too.
 
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sweetdiesel

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TheBac said:
Pat, the one thing we noticed at the track was that the problem stayed with either the race tune or the stock tune loaded. What should I look at in the race tune to see if what you're talking about is still active?

timing ECT fuel pressure ECT and there are a few others.I think if it was way off tom, that it would effect how the truck drives,But i never personally experianced it.

I bought a new sensor tonight. Heck, it was only $20. Will change it out and see what happens. From what I read on Alldata, the 03's only have one sensor. Is that correct?

.
Click to expand...

My 01 only has 1 sensor AFAIK its to the left of the thermostat housing:)
 
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Fingers

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If you lifted one side of the motor because of a bad motor mount, you may have damaged one of the grounds. A bad ground will give you the symptoms you describe.
 
TheBac

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Thank Jon. If you're talking about the grounds located under the front left corner of the engine under the water pump, I did look at those last night, and they still looked fine. Nothing looked out of place around the oil filter area either. Is there somewhere else I should check?
 
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TheBac

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We have a winner!

Yep....voting has ended for "2009 Dumbass of the Year"....and I win!

Found the problem. Bottom bale connector of main engine harness was loose. I must've loosened it when I removed the IC pipe to put the BD manifold and boost manifold in a couple weeks ago, and I never reset the clamp. The first drag run mustve pulled the connectors apart just enough to screw with everything. Yep...go ahead and laugh. I deserve it.

Truck runs fine now. :mad:
 
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Pondsy

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That's great it was such a simple fix - and YEAH I've been laughing for a good 5 minutes now!:rofl::rofl: Of course, I don't feel bad for laughing b/c I've been there too (just not in a racing context). :D
 
TIM Z

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Just saw this, I had a bad feeling but im glad it turned out to be simple Tom,

The lord was lookin out for ya!

Now get back to the track!:cool:
 
TheBac

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duramaximizer said:
You seem to be beating yourself up plunty over the deal.
Click to expand...

Darn it...that all came off wrong. It was supposed to be funny. Sometimes my sense of humor deals up some irony/sarcasm, and it just doesnt translate to writing. :rofl:

Yeah, Im lucky it wasnt worse. I may go to the track Sunday....not sure if I can.
 
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duramaximizer

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TheBac said:
Darn it...that all came off wrong. It was supposed to be funny. Sometimes my sense of humor deals up some irony/sarcasm, and it just doesnt translate to writing. :rofl:

Yeah, Im lucky it wasnt worse. I may go to the track Sunday....not sure if I can.
Click to expand...

LOL, but still.

We need a new best. Keep represent'n that bastard(so called by duramaxtuner) LB7.
 
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