Archived Cranks but won't start

[tajensen]

I hopped in my truck yesterday and went to turn it but all it would do is crank. I figured maybe somehow I lost my fuel prime so I bumped the starter a few times and even loosened the bolt to the VP44 until fuel came spurting out, but the engine still won't turn over. I got desperate so I ran to the local dealer and purchased a crankshaft position sensor for $110, swapped it out, and still nothing.



The worst part is I'm not seeing any codes when I cycle the key - all that flashes up is Pdone. I'm hoping it's not my VP44 gone bad (there weren't any typical warning signs) but I don't know where to go from here.



-Tim

 

[JFaughn]

Fuel pressure test , some squirting may not be enough .

 

[JLandry]

Tajensen,



I'm confused. You said all your engine will do is crank, but then in the next paragraph you said it won't turn over. I'll assume the first statement is the correct one.



Your signature says you have "FP gauges" so is it safe for to assume you have a fuel pressure gauge (or two) and good fuel pressure is indicated when you bump the starter to start the lift pump? Does the lift pump run for about 25 seconds when you bump the starter? If so, that pretty much rules out the lift pump as being the culprit.



Do you have a code reader or scanner to double check for Diagnostic Trouble Codes at the OBDII port?



You might try loosening one of the fuel injector fittings to check for fuel spray when cranking. (Note: The usual warning applies to not have your fingers and hands anywhere near the loosened injector line when cranking the engine as the spray can cut skin. Hold a piece of cardboard near the fitting to check for spray. ) If fuel sprays out, that could help rule out the VP44 Injection Pump being bad.



Please keep us posted and good luck.



John L.

 

[tajensen]

Fuel pressure test , some squirting may not be enough .

My FP gauge reads 15+ between the fuel filter and the VP44 when the LP is running but steadily drops while cranking. Is this what you mean by FP test?

 

[tajensen]

Tajensen,



I'm confused. You said all your engine will do is crank, but then in the next paragraph you said it won't turn over. I'll assume the first statement is the correct one.



Your signature says you have "FP gauges" so is it safe for to assume you have a fuel pressure gauge (or two) and good fuel pressure is indicated when you bump the starter to start the lift pump? Does the lift pump run for about 25 seconds when you bump the starter? If so, that pretty much rules out the lift pump as being the culprit.



Do you have a code reader or scanner to double check for Diagnostic Trouble Codes at the OBDII port?



You might try loosening one of the fuel injector fittings to check for fuel spray when cranking. (Note: The usual warning applies to not have your fingers and hands anywhere near the loosened injector line when cranking the engine as the spray can cut skin. Hold a piece of cardboard near the fitting to check for spray. ) If fuel sprays out, that could help rule out the VP44 Injection Pump being bad.



Please keep us posted and good luck.



John L.

Well I bought an Actron scanner and the test passed, no codes. I guess that's a good thing, but I'd rather have something to work with.

 

[tajensen]

Tajensen,



You might try loosening one of the fuel injector fittings to check for fuel spray when cranking. (Note: The usual warning applies to not have your fingers and hands anywhere near the loosened injector line when cranking the engine as the spray can cut skin. Hold a piece of cardboard near the fitting to check for spray. ) If fuel sprays out, that could help rule out the VP44 Injection Pump being bad.



John L.

I loosened one of the nuts behind the VP44 and saw no spray on the cardboard. I did the same thing on one of the nuts that screw into the valve cover, and no spray there either. Is there another test for the VP44?



-Tim

 

[JLandry]

Tim,



Does the lift pump run continuously and hold fuel pressure for about 25 seconds when you bump the starter? If yes, then the only conclusion I can come to is the VP44 injection pump must be bad, but trust me, I'm no expert.



At this point I'm not aware of anything else which would prevent the engine from actually starting (and running) if the starter will crank the engine over, you have proper fuel pressure, and no DTC's are showing up.



You'd think if something like the APPS (the throttle position sensor), the MAP sensor (boost pressure), or the crank angle sensor went bad, it seems like you'd get DTC's on those for sure. From what I've read here on the TDR, a failed VP44 isn't always accompanied by a DTC.



I even checked my Dodge shop manuals and diagnostic guides, but I'm not finding anything. I'll keep looking though.



John L.

 

[Missouri Mule]

tajensen, did you loosen a valve cover bolt or the nut on the injector line (at the injector)?

If no fuel at injectors it would seem that your vp44 bit the dust.

 

[tajensen]

tajensen, did you loosen a valve cover bolt or the nut on the injector line (at the injector)?

If no fuel at injectors it would seem that your vp44 bit the dust.

I loosened the nut on the injector line. There was a little fuel that dribbled out when I yanked on the injector line but no fuel sprayed while cranking. I get the feeling that any fuel pressure I'm seeing is a result of my lift pump and not the VP44. I might be placing an order with MWFI this morning :{



-Tim

 

[GordonG]

I had a similar pdoblem with my '02. It turned out to be the VP. Hopefully your luck is better than mine.

 

[GordonG]

Gee, I can't spell, and I have an '01 not an '02. Is today Monday?

 

[Missouri Mule]

Gary use the edit box for corrections.

Excuse me you must of used the quick reply it doesn't have a edit box.

 

[JLandry]

Tim,



I hope I'm not too late...



I just stumbled across something which might be worth checking out before you replace your VP44.



There are both a fuse and a relay in the (PDC) Power Distribution Center box (located in the engine compartment) which the ECM uses to power up the VP44. According to the Dodge service manual, when the ignition key is turned on, this relay gets energized and power is supplied to the VP44.



I'm thinking that if either the fuse blew or the relay went bad you might have a situation exactly like yours where the VP44 doesn't function, yet everything else otherwise appeared normal (engine would crank and lift pump would operate).



It's worth noting the Lift Pump is controlled independently from the VP44 and directly by the ECM.



As to not having any DTC's set under such a scenario, I'm theorizing one couldn't be set by the VP44 because it never gets powered up, and possibly the ECM wouldn't realize anything is wrong with VP44 because the truck never starts and runs.



From what I see in the service manual, the fuse which supplies power to the relay in question is number 3 labeled "Engine Cont 2" and the relay you're looking for is somewhat misleadingly labeled "Fuel Pump" (not to be confused with the Lift Pump which does *not* use a relay).



Before I pronounced that VP44 dead for all eternity, I would first check and/or replace fuse number 3 in the PDC and if it looks good, try swapping out the "Fuel Pump" relay with another non-essential relay also found in the PDC such as the one for the wipers (appropriately labeled as such).



Good luck,



John L.

 

[tajensen]

Tim,



Before I pronounced that VP44 dead for all eternity, I would first check and/or replace fuse number 3 in the PDC and if it looks good, try swapping out the "Fuel Pump" relay with another non-essential relay also found in the PDC such as the one for the wipers (appropriately labeled as such).



Good luck,



John L.

I did swap the fuse and relay a couple days ago and it didn't fix my problem... unfortunately. I think the new VP44 should be here in a couple days so then I'll be able to figure out if we've diagnosed this properly or not.



-Tim

 

[tajensen]

UPS came with my new pump yesterday. I feel like I got a pretty darn good deal from MWFI: new pump, o-ring, banjo fitting, and 4 FP line gaskets delivered 2 days after I placed the order, and all for under $1050. Oh, yeah, no core charge and a 30 day window to return the old pump with shipping paid by MWFI.



I spent my 2 days waiting on UPS by reviewing Diesel Dan's VP44 install videos (Putfile - Welcome to my homepage!). What a huge help! I was able to swap out the pump in about 5 hours, which is a fair bit faster than I was expecting. I'm sure it would have taken double that time had I not been using Diesel Dan's videos as reference.



After bolting on the last part, I ran the lift pump a few times then went to fire up the truck. Unfortunately, it didn't start up right away, but after some persistent cranking it began to sputter. A few more tries and it was running good as new.



Thanks to all who helped diagnose my starting problem, and especially to Diesel Dan for his extremely helpful videos.



-Tim

 

[JLandry]

Tim,



Glad to hear you solved your problem. Thanks for letting us know how it turned out.



Can I ask how many miles you had on your engine when the VP44 quit? I have over 90,000 miles on mine on the original VP44 and I'm starting to get nervous.



Drive safe,



John L.