Diesel Boys enter please - need help!!!
 

Hey guys, 2004 6.6 duramax 4500 series, cranks but wont start Did all the normal fixes. Fuel filter mount isnt cracked, reluctor wheel is not loose, changed crank and cam sensors. Not sure fuel is getting to the high side. Motor will start with a shot of starting fluid. I KNOW not good!!!! Just checked to see. Checked all connections, scanner says not seeing glow plugs and injector pulse. Im at a loss forsure. Truck is in NNJ Oakland right by NJDMV in center of town. Anybody local can stop by and give a hand or insight. I WILL PAY you for your time , not looking for a freebie. I need this truck back on the road its leaf season lol. Any input or help would be great, thanks guys in advance Don

Does it throw any codes?

Is there fuel in tank?

Any kinks in feed or return line?

Drained the WIF lately?

Does it smoke when you crank?

Can you access a tech2 or similar to show rail pressure while cranking? (That would also let you see cranking rpm to verify sensors work)

Will these trucks show a tach signal while cranking if cps is good?

just threw PO340 code cam sensor!!!! ughhhhh

You have the LB7, go check :wink:

OP, when you changed fuel filter, I assume you primed it after words? It takes a while to get the fuel up to filter head and air out.

this truck has 49k miles, i have rebuilt a 01 and 03 complete injector and fuel pump, one of the motors had 2 bent pushrods also. lol this "black magic" electrical stuff drives me nuts

yes LT checked all those, and no smoke while crank

yes have pressure on the low side, no air thru manual prime.... whos close to Oakland? I have $$$, lol

Sounds like you have a lovely electrical gremlin, did you check the pins in teh harness side? Nothing loose in the CPS sensor hookup?

I believe on LB7 motors there is a bale connection up on top near valve cover, check that, and all of em really for anything corroded or loose.

I would def verify that the ECM is seeing rpm, and then verify you have correct voltage at sensor. If those check out, you may have a bigger issue.

http://www.dieselbombers.com/chevy-g...on-sensor.html

Freakin batteries are dead! But on the lly, it doesn't register as the gauges self check after start and are dead prior.

Ah ok.

Don, you really are gonna need someone with a tech2 to scan I think. You can do some stuff with a DVM but its easier to hook up and scan.

DTC P0340

CIRCUIT DESCRIPTION
The hall effect camshaft position (CMP) sensor produces 3 ON-OFF pulses for each revolution of the camshaft. The CMP output is pulse width encoded. The electronic control (ECM) module uses the CMP and crankshaft position (CKP) output pulses to determine the engine speed and position. The CMP is connected directly to the ECM by the following circuits:

12-volt reference
Low reference
CMP sensor signal

If the ECM does not see a CMP signal for more than 2 seconds, DTC P0340 will set.

CONDITIONS FOR RUNNING THE DTC

The ignition is ON.
The engine is turning faster than 50 RPM.

CONDITIONS FOR SETTING THE DTC
The ECM does not see a CMP sensor signal for more than 2 seconds.

ACTION TAKEN WHEN THE DTC SETS

The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC

The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.

DIAGNOSTIC AIDS

An intermittent CMP sensor signal may cause DTC P0340 to set. Wiggle the wiring harness with the engine running and observe the Cam Signal Missed parameter of the scan tool. If the parameter indicates anything other than 0, there is an intermittent condition.
A short from the 12-volt reference circuit to the low reference circuit internally in the camshaft position (CMP) or crankshaft position (CKP) sensor can cause all three DTCs P0336, P0340, and P0016 to set.
If the CMP sensor signal is lost while running, the engine will operate normally. If the CMP sensor signal is not present on start-up, the engine will not start.

Most of the testing is done with a digital multimeter actually.

Can't see rail pressure etc though, just helps narrow it down to def sensor/harness.

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This info provided is based off of the 340 code he pulled.

Red - 12 volt
Pink/Black - Low Reference
Brown/White - Cam Position Sensor Signal

Ya wasn't thinking, should be enough info now to test all teh things! :nod:

checked all harnesses n grounds, fuses, once again, put a light on a injector and nothing, ordered another 2 cam sensors. I have a 05 with the same motor. Im gonna pull that sensor when it comes back to shop later and hope for a miracle..

Bust out the DVM and test harness, don't keep throwing parts at her.

I came in thinking maybe i could help but considering I have a 12v cummins... im useless here lol

Follow the diagnostic tree I posted, you will find the cause of the 340 code and most likely the no start issue.

Happy friday, trick or treat. and now the glow plug circut...

Glow plug code indicates the module went, but it shouldn't cause it to not start I think.

The CKP sensor, you replaced and said the reluctor was not loose correct?

So you have a new cam and crank sensor in now?

DTC P0335

CIRCUIT DESCRIPTION
The hall effect crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. There are 57 teeth on the front of the crankshaft sprocket, plus a sync gap. The CKP sensor will output an ON-OFF pulse as each window passes the sensing element. The CKP sensor is connected directly to the engine control module (ECM) by the following circuits:

The 12-volt reference circuit
The low reference circuit
The CKP sensor signal circuit

CONDITIONS FOR RUNNING THE DTC

The engine is cranking or running.
The camshaft position (CMP) sensor signal is present.

CONDITIONS FOR SETTING THE DTC
The engine control module (ECM) determines no signal from the CKP sensor for less than 8 seconds.

ACTION TAKEN WHEN THE DTC SETS

The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails-The control module stores this information in the Freeze Frame/Failure Records.

CONDITIONS FOR CLEARING THE MIL/DTC

The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.

Do you want me to post the diagnostic steps?