Problems - Stalling when shifting to drive and hard starting when hot. Ideas?????

[SASQCH]

History of the truck.

Truck was purchased in 2002 with 43K miles.

Engine and transmission were stock except for a K&N drop in air filter.

Early 2003 installed a PowerMax programmer from TST which displays boost, transmission temp, and EGT.

Late 2003 installed a PacBrake, TripleLoc (three clutch disk) torque converter, and HP valve body from TST.

2007 spring had check engine light and intermittent hard starting local diesel shop diagnosed it as a fault between primary and secondary computer and cleared the code (don’t know what the code was). They checked my fuel pressure which was around 10 at idle and much less under static 2400 rpm throttle. He advised getting a new fuel lift pump.

Aug 2007 installed a fuel pressure gauge, engine oil temp gauge, FASS 95, and rebuilt VP44. Fuel pressure 17 at idle 14.5 at WOT.

July 2008 installed MagHyTech Double Deep transmission pan and 14CM turbo exhaust housing on the HX35.

December 2008 began experiencing hard starting when hot after sitting shut off for more than 5 minutes. Truck had check engine light P0336 CKP sensor. Took the truck to Lithia Dodge in Anchorage who kept it for a week and said they couldn’t find anything wrong and the CKP was fine. I told them to change it anyway. They wouldn’t do it and told me that I had to remove the Fass 95 and any other aftermarket items installed on the truck (Pac brake, converter, valve body, programmer, etc.) as they didn’t understand how they worked or could affect the diagnostic equipment. I told them where to put their dealership and where I would not purchase my next vehicle. Took the truck home and changed the CKP with one from Cummins. Hard starting problem solved.

I Installed 18” of clear fuel line at a high point before the vp44 to be able to check visually for air in the supply fuel line. (I have never seen any air)

July 2009 began experiencing hard starting when hot and sitting more than 5 minutes again along with stalling when shifted into drive from park or neutral. I Cleaned the Map and IAT sensors. No joy.

I installed a set of Edge 80 hp injectors, new connector tubes and O rings, and a CoPilot transmission controller for the PacBrake. I also soldered all connections for the PowerMax programmer and CoPilot. Starting and shifting problems went away.

Aug 2009 installed BHAF and 4” MBRP exhaust.

February 2010 Shifting and hard start problems returned. Truck starts fine after sitting overnight and completely cooling off, but stalls when shifted into drive. Engine does not idle smoothly seems to hunt for a idle rpm to settle into. If left idling for a longer period (30 min) the hunting grows worse until the tachometer is swinging 100 or so up and down. Revving the engine settles the hunting down a bit but the hunting continues.

When the engine stalls after shifting into gear it usually re-starts on the first try.

The stalling is worse when the truck is cold than when hot.

The restart problem is worse when the truck is hot than when it is cold.

Bringing the engine rpm up to about 900 will usually prevent the stalling when shifting. Sometimes after stalling several times and then getting on the road just idling along at 5mph or so the engine will suddenly go rumph, rumph, rumph, rumph, rumph quickly like it’s going to stall then catches itself and revs a little each time to prevent a stall.

I have checked the fuel return line, rear banjo bolt, and all fittings and clamps for fuel leaks and found none. I have replaced the VP44 fuel return check valve. I have re-calibrated the APPS memory.

March 2010 I noticed erratic boost pressure readings sometimes the boost pressure would read zero under partial throttle where it should have been reading12 or 14 lbs boost. Replaced MAP sensor and the boost reading problem went away.

April 1 2010 took the truck to Cummins Northwest to purchase a new IAT sensor suspecting the stalling problem could be due to a faulty IAT and the cold outside air.

While there a mechanic looked at the truck and noticed the sticker saying the last ECM program re-flash was in 1999. He thought a re-flash with the latest program might help the problem and I agreed. He re-flashed the ECM and kept his scan tool hooked up shut off the truck and restarted several times and noticed the IAT temp reading sometimes went to and stayed at 160. When it went to 160 the truck would not re-start until enough cold air came through to cool the IAT to below a 130 reading.

I went home, changed out the IAT with the new one from Cummins, and took it for a test drive.

Still have the stalling and hard starts but not as bad and the idle rpm hunting seems to have gone away.

Yes, I have checked the grounds on the ECM and PCM.

I have also cleaned all battery connections and used dielectric grease everywhere.

So I'm Kind of out of ideas here.

Today I'm going to get it up to operating temp then shoot the exhaust temps of each port on the manifold looking for enough variation to indicate a plugged injector or one that may have a lower pop off pressure.

If I can't find anything there I may pull the connector tubes part way out and rotate them so the O rings seat in different positions and see if that does any good.

I'm open to any and all suggestions to solve these problems.

Thanks

Jim

[ISX]

Crazy thought here. Maybe the torque converter is locking somehow for a second? I have a manual locking switch on my ford and I forgot to unlock it when slowing down and it chugged and all, I think if I was stopped and locked it, it would stall.

road just idling along at 5mph or so the engine will suddenly go rumph, rumph, rumph, rumph, rumph quickly like it’s going to stall then catches itself and revs a little each time to prevent a stall. Exactly what my ford did, did it jerk each time it "rumphed"? The computer keeps it from stalling so thats why it didn't stall while moving.

Not sure on this but is a thought..

[SASQCH]

Crazy thought here. Maybe the torque converter is locking somehow for a second? I have a manual locking switch on my ford and I forgot to unlock it when slowing down and it chugged and all, I think if I was stopped and locked it, it would stall.

road just idling along at 5mph or so the engine will suddenly go rumph, rumph, rumph, rumph, rumph quickly like it’s going to stall then catches itself and revs a little each time to prevent a stall. Exactly what my ford did, did it jerk each time it "rumphed"? The computer keeps it from stalling so thats why it didn't stall while moving.

Not sure on this but is a thought..

Good thought but I don't think that is causing it for two reasons.

1. The Truck itself don't surge/jerk forward at all like when the TC locks up.

2. The CoPilot controls when the TC normal lockup occurs (I can change the lockup speed setting) and when it goes to lockup there is a light that comes on, and the light doesn't flash at all.

When the truck does go into TC lockup it is quite distinctive when lockup occurs as the tachometer reflects it and the seat of the pants feels it.

I had a manual lockup switch before the co pilot and have done the same as you did so I do know how that feels in the truck. I also accidentally flipped the switch once when the truck was idling and it does kill the motor, that's why I bought the CoPilot and have been real happy with it.

Thanks for the response and keep thinking on it as I said I need more ideas to explore in tracking this annoying little gremlin.

Jim

[ISX]

Yeah I forgot to ask if it jerked. So hmmm. It's almost like there's air bubbles hitting and missing. But you got that checked out too with the clear hose. But you say you rev it up and it prevents stalling which really makes me think an air issue. Hmm, but why only when you shift to drive. Yeah I'm drawing blanks now I'll keep thinking. I'm sure some others will come in to feed the fire.

[SASQCH]

Yeah I forgot to ask if it jerked. So hmmm. It's almost like there's air bubbles hitting and missing. But you got that checked out too with the clear hose. But you say you rev it up and it prevents stalling which really makes me think an air issue. Hmm, but why only when you shift to drive. Yeah I'm drawing blanks now I'll keep thinking. I'm sure some others will come in to feed the fire.

It don't stall when shifting into reverse just drive which I find a little strange. You would think the load to the engine would be similar between drive and reverse.

The converter has an 1800 rpm stall so there is a load transmitted when it goes into gear. It's strong enough that I have to keep my foot on the brake when it is in gear idling or it will start to move. On level ground it will actually accelerate at idle to shift to second and third upwards of 20 mph or so with no throttle.

It has crossed my mind that it might be an APPS idle position problem and I've contimplated putting a Timbo on it but havn't yet.

Thanks

Jim

---------- Post added at 04:00 PM ---------- Previous post was at 01:18 PM ----------

update

OK, I took the truck out and got it up to operating temp 190 with oil at 180.

Pulled in the drive put it in park and let it run a few minutes to normalize the temps then read each exhaust manifold temp within an inch from the head. Then I put it in drive with the parking brake set and let it run a few minutes to normalize then re-read the temps.

This is what I found:

In neutral 1= 268 2=298 3= 291 4=315 5=268 6=270 spread of 47 degrees between 1 and 4.

in drive 1=290 2=300 3=369 4=391 5=356 6=315 spread of 101 degrees between 1 and 4.

The injectors only have around 12K miles on them and were pop tested.

[gassernomore]

If I am reading correctly the last time you checked codes was in 2007. Have you checked for them recently? When my VP went out it would stall when shifting and it was hard to start as well.

[SASQCH]

If I am reading correctly the last time you checked codes was in 2007. Have you checked for them recently? When my VP went out it would stall when shifting and it was hard to start as well.

Yup, I carry a code reader in the truck and check for codes on a regular basis when ever something don't seem right. There are no codes. Also Cummins Northwest checked the codes when they reflashed the ECM yesterday. No Codes.

[Mopar1973Man]

I've got to think on this one... Give me some time to read over and think aobut it...

[ISX]

Idea #2. You say the CKP fixed it, then the injectors pacbrake and all that fixed it. But maybe the CKP has a loose connection somewhere or frayed connection or something. You say the TC is very strong and will accelerate while idling, so I am thinking when you put it into drive, the engine lugs at first and then compensates, but with the CKP screwing up, it either stalls or idles weird because of the haywire readings it is getting. It doesn't know what to do. I think when you were messing with round 2 of things (injectors, pacbrake) that you hit the loose connection somewhere and it fixed it until it loosened back up. It could be further along the line than just the sensor wires, you would have to trace every wire that had to do with that sensor all the way back to the ecm. So theres another idea for ya

[guesswho512]

my trucks rpms used to "bounce" by about 50 or100 before i did the valve lash.i thought i read at dodgeram.org that cylinder one was supposed to be the hottest cylinder due to the way the airflows it usually is slightly richer.you did use new coppers and o's on those injectors?(you did make sure those original coppers came out?)my vp will "die" for split second(driving with and without cruise control, and parked) it has never died, just the split second thing and it picks back up like nothing happened. leaves no codes. using my code reader...i can monitor certain parameters while driving. can u use yours the same way and watch the IAT for data you know isn't right?

[Mopar1973Man]

I think ISX is right... It's going to be a sensor or wiring issues somewhere. As for the hard starting you could try disconnecting the lift pump and see if the VP44 is hyper-sensitive to fuel pressure. http://mopar.mopar1973man.com/cummins/2ndgen24v/fuel-pressure/fuel-pressure.htm

[SASQCH]

my trucks rpms used to "bounce" by about 50 or100 before i did the valve lash.

i thought i read at dodgeram.org that cylinder one was supposed to be the hottest cylinder due to the way the airflows it usually is slightly richer.

you did use new coppers and o's on those injectors?(you did make sure those original coppers came out?)

my vp will "die" for split second(driving with and without cruise control, and parked) it has never died, just the split second thing and it picks back up like nothing happened. leaves no codes. using my code reader...i can monitor certain parameters while driving. can u use yours the same way and watch the IAT for data you know isn't right?

I set the valve lash when the new injectors I put in the injectors in July of 09.

The injectors were new and came with new coppers and O rings.

All of the original copper washers were accounted for when the old injectors were removed.

My code reader is an inexpensive model that doesn't provide live data. (not a scan gauge II although I'm now thinking of getting one)

The IAT got replaced and is now a new one. (I know that don't mean it reads correctly)

Thanks

Jim

---------- Post added at 08:54 AM ---------- Previous post was at 08:28 AM ----------

I think ISX is right... It's going to be a sensor or wiring issues somewhere.

As for the hard starting you could try disconnecting the lift pump and see if the VP44 is hyper-sensitive to fuel pressure.

http://mopar.mopar1973man.com/cummins/2ndgen24v/fuel-pressure/fuel-pressure.htm

Both the MAP and IAT sensors have been replaced with new ones now. The MAP was replaced the last part of March and the IAT on April 1.

I will check the connections and wires to the CKP and cam sensors (98.5 has both sensors) and also the IAT and MAP sensors.

I havn't tried disconnecting the lift pump see if the VP44 is hyper-sensitive to fuel pressure, what I have tried is:

1. Starting the truck without waiting for the wait to start light to go out or LP pressure to cycle up and back down (like one starts a gas vehicle) Sometimes starts sometimes not.

2. Let the pressure cycle up and back down bump the starter then quickly off and hit the starter when the pressure gauge is partially up 8 - 10 psi. sometimes starts sometimes not.

3. Bump the starter, let the pressure come up full and wait for 10 to 15 seconds and try to start it. This works about 70% of the time.

Longer crank times seem to make no difference, if it don't start on the second or third revolution of the motor, It wont start on that try.

I've read your page many times and given the link on more than a few occasions to others on the Cummins Forum.

I may have to put in the cutoff switch for the lift pump. My wife will be thrilled, she says the truck looks like the cockpit of a 747 now.

Thanks

Jim

---------- Post added at 05:25 PM ---------- Previous post was at 08:54 AM ----------

UPDATE

Today I took off the apps and pulled the electrical plug cleaned it and applied dielectric grease.

Pulled off the electrical T connector from the PowerMax between the MAP sensor and the factory wiring harness cleaned and applied dielectric grease.

Cleaned and greased the connectors to the PowerMax in it's wiring harness.

Traced as much of the sensor wires as I could get to looking for wire damage and found none.

Yesterday I added a bottle of STP diesel injector to the 2/3 full tank of fuel.

Took the beast out and warmed it up to operating temp.

It seems to be idling a little better and it seems to be starting a little better, but it's still not where I want it to be.

On the plus side the PowerMax is functioning better than it ever has. At 60 mph on the freeway with the PowerMax on 9 of nine I floored it, the trans dropped out of OD, the boost came up to 42, and the egts went to 1450 and the truck launched like it had a JATO bottle in the bed. I only let it run like that for about 5 seconds then let off. I know I need to keep the boost under 35 or so because the HX35 is running outside of it's design parameters at pressures above 35.

Next is to take off the starter and check the CKP connection and wiring, the Cam sensor connector and wiring, and also clean and grease the ECM ground.

[ISX]

Ah yes. Getting somewhere. I am betting your problem lies with that CKP. It is the sensor that makes the most sense to be causing all these issues, to me anyways. I am kinda beginning to think its not the CKP itself, but the wiring rather. I don't see replacing it and then somehow it goes out again in a year or whenever the problems started acting up again, I think you jiggled the wires going to it when replacing it and gave it a solid connection but they have jiggled loose again. Make sure each wire is pressed into the connectors and haven't been pulled out also. I'm gonna put all bets on bad CKP connection

[SASQCH]

Checked and cleaned/re-greased the connections and wiring to the CKP and Cam sensors. It made no difference in the problem. I could find no problems in the wiring (did a lot of jiggling).I'm out of ideas at this point other than to pop the connector tubes and re-seat the O rings into a different position by rotating the tubes a little.Any other thoughts?

[ISX]

Man, and I had a $100 bet It's hard telling anymore, the CKP fixed it, then the chip and injectors fixed it, it's not consistent at all. Might have been both things which just happen to have the same effects, so the CKP was bad and you replaced it, then injectors went bad causing same symptoms, new injectors fixed it.. So I would say it's the injectors or something else is messing up that is also causing the symptoms. The hard hot restart and easy cold restart and more stalling when cold is throwing me for a loop. Does it even act like it will stall in reverse, ever?

[SASQCH]

Man, and I had a $100 bet It's hard telling anymore, the CKP fixed it, then the chip and injectors fixed it, it's not consistent at all. Might have been both things which just happen to have the same effects, so the CKP was bad and you replaced it, then injectors went bad causing same symptoms, new injectors fixed it.. So I would say it's the injectors or something else is messing up that is also causing the symptoms. The hard hot restart and easy cold restart and more stalling when cold is throwing me for a loop. Does it even act like it will stall in reverse, ever?

Hey, man you can send me a check for the $100. Nope don't stall in reverse. I have figured out that when it don't start when warm, if I just bump the starter so the pump runs and I wait about 10-15 seconds it will start right up almost all the time. If it don't start, then when I turn the key on and the pump starts running again, If I hit the starter when the pressure gauge hits around 10 psi, it will start. So now I'm thinking there is an air leak in the return line somewhere and the 10-15 second run re-primes the VP. That's why I thought about rotating the connector tubes in the holes to see if an O ring was leaking a little air. Since it only seems to do it when the engine has been up to operating temp (190) and has cooled for a few minutes, my thoughts are now running towards warm fuel being thinner than cold fuel and metal expansion from heat causing larger clearances. (grabbing at straws here) I guess I could put in the old VP check valve on the return line that I replaced when I was having problems before (didn't fix the problem so I kept the old one) and see what that does. I know hard starting is an indication of a torn diaphragm in the VP44. If it turns out the truck has a torn diaphragm in the VP I'll live with it until the VP dies.

[ISX]

Hey, man you can send me a check for the $100.

Nope don't stall in reverse.

I have figured out that when it don't start when warm, if I just bump the starter so the pump runs and I wait about 10-15 seconds it will start right up almost all the time. If it don't start, then when I turn the key on and the pump starts running again, If I hit the starter when the pressure gauge hits around 10 psi, it will start.

So now I'm thinking there is an air leak in the return line somewhere and the 10-15 second run re-primes the VP.

That's why I thought about rotating the connector tubes in the holes to see if an O ring was leaking a little air.

Since it only seems to do it when the engine has been up to operating temp (190) and has cooled for a few minutes, my thoughts are now running towards warm fuel being thinner than cold fuel and metal expansion from heat causing larger clearances. (grabbing at straws here)

I guess I could put in the old VP check valve on the return line that I replaced when I was having problems before (didn't fix the problem so I kept the old one) and see what that does.

I know hard starting is an indication of a torn diaphragm in the VP44.

If it turns out the truck has a torn diaphragm in the VP I'll live with it until the VP dies.

That has been running through my head the entire time. But, heating up would generally cause things to fit tighter since the parts inside the engine will be warmer than external (air cooled) parts. My ford is a perfect example. If I plugged it in, it would start up instantly in any weather, if not, it would start up like crap up to 90F. That thing would warm the coolant way up past 90 and I think it was just enough to seal all the gaps, 90F and under sure wasn't enough, but anything above it would just make it a starting competition between it and my 12V.

[Mopar1973Man]

Ok... I got some insite... I had a guy that had been calling me on a regular basis with a P1960 code. Even after replacing the sensor and the code still hung. finally giving in to the dealer for $240 bucks roughly to come to find out the ECM connector and the cam sensor connectors wore out. They just were not making a solid cotact with the ECM and Cam sensor. So I know this isn't exactly you case but you might have to get creative and double check connectors to see if there is a weak connection.

[SASQCH]

I hadn't thought about the ECM connector at all, I'll check it out.I'm putting a scan gauge on it today so I can monitor more parameters on the road.I have a smarty coming also to be able to turn on high 3 cyl idle and also take advantage of the timing added options for better mileage when running empty.

[SASQCH]

UPDATE

I put a smarty program on the truck (#3) and took it out to see how it ran (normal driving - no wot or anything like it).

When I started it I noticed that when I turned on the key the fuel pump didn't run for 2 seconds like it always has before.

Once the starter engaged and the truck started the fuel pump came on and The pressure went to 17 psi.

I backed out of the garage put the truck in drive and it died (like always) put it into neutral and started it.

The fuel pressure gauge started going crazy (first time it has ever done this) the needle jumped from 5 to 12 back and forth never going under 5 and never going over 12 after about 10 seconds of this without stabilizing of going to the normal 17, I shut the truck off.

I restarted it and the fuel pressure went to 17 and stayed.

I don't know what that was all about, The only thing I can figure is maybe the return line drain might have stuck open????

The hard starting when warm has gone away completely It starts every time now.

The idle hunting has also gone away, don't know if it cleared up from the injector cleaner or the new ECM program from the smarty. It idles at 745 rpm according to the scangauge.

The last thing is if I let it idle for a minute or longer when warm, it does not die when put into gear.

I'm suspecting more and more that the VP44 has a torn diaphragm that is causing the problems over an electrical issue.

It's puzzling because the VP44 has never had low fuel pressure because I put in the FP gauge, FASS 95, and rebuilt VP44 all at the same time.

I guess it's possible that the VP44 re-builder didn't replace the electronics and diaphragm module when it was rebuilt.

As I said before If it's torn I'll live with it until the IP dies.

I still need to clean and check the ECM connection.