Engine/Transmission (1998.5 - 2002) Trouble Starting - LOts Of Cranking When Warm

[RSchwarzli]

I am posting this on behalf of one of our not too web savvy Ontario members.



About mid May he fried his lift pump on his 99 2500 Auto. Did not know it until he fried the VP44 as well. So he replaced both the VP44 and the lift pump. All seems to work OK during driving, towing, etc except warm starts. When he starts the truck in the morning it starts right up. Same as when he leaves work at night. The issue is when he does stops for lunch, fuel, etc and then tries to restart. Says the truck just cranks and cranks. Has been doing this for a month and a half now.



Anyone with thoughts or suggestions?



As for the truck, it is all stock right down to the exhaust. Truck has about 300 K on it.



If you need more info, let me know!



Thanks!



Robert

 

[FourBarR]

You need to get the codes read,for starters. That would save a lot of guess work and throwing parts at it.

 

[RSchwarzli]

From what I gather, it is not throwing codes. That was my first question. No CEL.



Should it be checked for soft codes? Will the ignition check reveal those or do we need a OBD2 scan?

 

[BDahm]

My 02 does the same thing only long cranking when its cold(morning) but after its been running it starts right up. Possibly the ecm or the pump itself.

 

[JLandry]

I'd definitely check for stored trouble codes and also ask if he's verified the fuel pressure is adequate during the difficult starts.



John L.

 

[JGamble]

I had the same problem after I bought my truck. It started about two months after I had bought it. My FP was running 7-9 on a FASS HPFP. I thought it was normal. Well, the hot season started, and it would crank and crank during a hot startup. Finally, I was going from CVS to home, to see bluish white smoke and the truck went into LAG mode... . oh god. Thought I fried the VP, found out that the LP died and the VP is still good... knock on wood. Might I suggest that the LP pump your friend had stuck in was a reman and not a new one? Sometimes, reman's will NOT be what you expect. The symptoms you speak of are signs of a bad LP. It very well might throw a P1693 Code to start off with, that is one of the many codes when those parts tend to go south. Let us know and god speed... ...



Regards and Best of Luck,

John

 

[LowFly]

With the FASS system... . hard start issues are usually due to a high mileage VP44. The way to test this is to when you are experiancing the hard start issue... try unplugging your LP and if the truck fires right up then you have found your issue. The LP is trying to feed a lot of fuel and a lot of PSI to the VP44 and it does not like it. It is almost always NOT the LP.

There are two ways to fix this IF you have the FASS system.

1. Buy a Hobbs Oil Pressure Switch and mount it to your oil filter base. There is a port for it. Then you need to hook up the ground wire of your FASS fuel pump to the oil pressure switch. When the oil pressure switch detects oil pressure it will kick the pump on.

2. we have a wiring schematic that will allow you to modify our wiring harness so that the ECM can control when the pump kicks on.

If you have this issue and you have a FASS system please PM me so that i can call you. Thank you all for your continued business and have a great day!

 

[RSchwarzli]

I'd definitely check for stored trouble codes and also ask if he's verified the fuel pressure is adequate during the difficult starts.



John L.

Funny, I have told this gentlemen for 3 years to get a FP guage. After the issue a month ago he decided to get one now. IS currently working on purchaing one. But no, have not verified FP with a guage.

I had the same problem after I bought my truck. It started about two months after I had bought it. My FP was running 7-9 on a FASS HPFP. I thought it was normal. Well, the hot season started, and it would crank and crank during a hot startup. Finally, I was going from CVS to home, to see bluish white smoke and the truck went into LAG mode... . oh god. Thought I fried the VP, found out that the LP died and the VP is still good... knock on wood. Might I suggest that the LP pump your friend had stuck in was a reman and not a new one? Sometimes, reman's will NOT be what you expect. The symptoms you speak of are signs of a bad LP. It very well might throw a P1693 Code to start off with, that is one of the many codes when those parts tend to go south. Let us know and god speed... ...



Regards and Best of Luck,

John

Right on! It was a reman I believe. So was the VP44. Ironically, they apparently had to rebuild the VP44 a second time as it was as it was not done right the first time.



So I guess step one is to get a FP test. That should confirm alot. Will also check the codes.

 

[RSchwarzli]

With the FASS system... . hard start issues are usually due to a high mileage VP44. The way to test this is to when you are experiancing the hard start issue... try unplugging your LP and if the truck fires right up then you have found your issue. The LP is trying to feed a lot of fuel and a lot of PSI to the VP44 and it does not like it. It is almost always NOT the LP.



There are two ways to fix this IF you have the FASS system.



1. Buy a Hobbs Oil Pressure Switch and mount it to your oil filter base. There is a port for it. Then you need to hook up the ground wire of your FASS fuel pump to the oil pressure switch. When the oil pressure switch detects oil pressure it will kick the pump on.



2. we have a wiring schematic that will allow you to modify our wiring harness so that the ECM can control when the pump kicks on.



If you have this issue and you have a FASS system please PM me so that i can call you. Thank you all for your continued business and have a great day!

He does not have a FASS. Yet! Might have to get there.....

 

[Ron Bissett]

Locate remove caean the Air intake sensor ,this should be done to save problems ,with starting ,wasting fuel , etc. Ron

 

[RSchwarzli]

Where would that be (as in what side of the intercooler)?

 

[Midnite]

The IAT sensor is on the driver's side of the engine, fairly far back. If you know where the MAP sensor is, the IAT is just a bit further back.

Hopefully someone can post a diagram from the service manual.

Mike

 

[RSchwarzli]

OK. I think I located it. Right infront of the rear coolant plug. Wills see what it looks like. Also he ordered a fuel pressure guage today... .

 

[Ron Bissett]

Sorry have ben offline for a few days . AIS can and will clog up causing problems . To remove ,disconnect the elect wires then use a 13 mm socket to remove the sensor careful dont let any dirt fall in the hole ,I use some spray penitrating oil first then use the socket ,to clean after inspecting use a spray of cleaner or penitrating oil then use carb cleaner wipe clean . There is a test found it the manual that I have never used just cleaned a and reinstalled worked for me . A new sensor a few years ago was said to be twenty dollars who knows now . If you clean it most time it will work fine If you don't clean it sooner or later it will plug up . Ron