GP or maybe fuel issue?

[cshaw07]

Well, I'm stumped again. My 09 is having a warm starting issue. Yesterday I got home from work and tried to start it, my glow plugs cycled and it cranked for about 5-10 sec and it fired up. I drove it the the car wash and around a little bit then brought it back home. It got up to operating temp. If I shut it down and then immediately try to start it, the GP solenoid doesn't click but it will fire right up. If i let it sit for about 10-15 min or longer the solenoid still wont click and i can crank and crank until the batteries die without it starting. Let it cool down and try again, GP solenoid clicks and it will start up in 5-10 sec. I tested the yellow wire on the GP card when it was cold and got 800ohms. I replaced the GP solenoid and by passed the resistor giving it straight 12v. My glow plugs are of unknown age, but i tested them all and got 1.2 to 1.5 ohms of resistance on all of them. Any ideas? Should the glow plugs come on when the truck is warm even if just for a few seconds? Not sure if i said it in my "charging" thread but I am new to diesels. Been dealing with them for about a week now, I feel like i know enough to get myself in trouble . Ive ordered a spin on filter setup to get rid of the square block filter setup. But it doesn't actually sound like i have a fuel issue if it will start up pretty good when cold. Maybe my coolant temp switch is going bad? Possible bad injection pump? I'd love to start driving this thing everyday, but I'm a bit hesitant.... i HATE getting stranded and its already stranded me once in a week.

 

[GPrez]

A couple of things I would try would be to replace the glow plug temperature sensor, and the glow plugs if they are old as you describe even if testing OK. Those are 2 easy things. Both can be purchased from CUCV electric.

I am fairly certain the glow plugs should cycle on for a brief second even if the engine is warm. It should not take 5 to 10-seconds of cranking even when cold for your engine to start. If your still 24V to the starter it should fire almost immediately. If a 12V conversion was done it might take 2 to 3-seconds of cranking from my experience.

Another thing to try is to have someone cycle the key on while you hold a test light on each glow plug and make sure each is getting power when energized and cycling off hen the relay cuts off. You can do the same when it is warm to see if they are energizing briefly when starting a warm motor.

With 5 to 10-seconds of cranking to start it sounds like the glow plugs are not getting warm enough or some are bad.

 

[cshaw07]

looks like im going to replace the temp sensor and see what happens, then ill do the glow plugs. I dont know how old they actually are, but i guess they could be an issue. I did test for continuity from the glow plug wire ends to the bottom wire of the solenoid all all tested fine. I tested for 12v at the glow plug with the key on and got about 6.5-7V after i did the resistor by pass, shortly after the solenoid died so i replaced it and have yet to test it again for 12V at the plugs. Id assume that with the new solenoid id be getting the full 12v to the plugs but i guess you never know. When i go out and crank it when its cold you can hear it trying to fire for those 5-10 seconds and then it will start up. Thanks for the help.

 

[Corvette1974]

Read the CUCVElectric "GP theory of operation" it is a good read and fully explains the system and its logic.

Moreover, Like stated before, The GP relay should cycle no matter the conditions of the engine. I always wait until the light goes out, no matter how recently run/hot the engine is. It always runs about an 8 second cycle when hot, maybe longer when cold....regardless, by following the "half pedal depressed when above 32 degrees" it starts immediately, faster than any diesel I know of, even new ones.

I have new GPs and a new GP relay (plus about new everything!), and it operated perfectly. Look into the GPs, even if they check out, they may have lost some of their juice over the years.

Will

 

[TCUCV]

GPrez ~ the glow plug temp sensor, is that the same thing as the Glow Plug Switch in the manual?

 

[GPrez]

GPrez ~ the glow plug temp sensor, is that the same thing as the Glow Plug Switch in the manual?

I don't know of a "Glow Plug Switch" listed in the manual. Can you reference which TM and page?

In any event I do not believe it is the same as the glow plug temperature sensor. The temperature sensor is mounted on the top rear left side of the head, and has 2-wires running to it. Remove the air cleaner and you'll see it.

 

[Warthog]

Read the CUCVElectric "GP theory of operation" it is a good read and fully explains the system and its logic.

Are you refering to AntennaClimber's sticky in the CUCV Forum? Two different people.

http://www.steelsoldiers.com/cucv/62477-gp-module-theory-operation.html

 

[ccf460]

I added a momentary switch on the signal side of the GP relay to run the glow plugs whenever I want to ( the glow plug controller card is still in place and functions as it should, I added the switch before replacing the relay and glow plugs). The switch is a cheap way to test your theory of glow plugs not running enough, plus it is a nice backup in case your card takes a dump and leaves you stranded somewhere. I never use it anymore after replacing everything, but is a nice piece of mind having it there.

 

[mistaken1]

When your engine is warm and will not start try pouring a little cool water on the injection pump, see what happens.

Also is it safe to assume you have cleaned the return check valve on the IP?

 

[Corvette1974]

Are you refering to AntennaClimber's sticky in the CUCV Forum? Two different people.

http://www.steelsoldiers.com/cucv/62477-gp-module-theory-operation.html

Haha well I guess I got the two confused! That (the GP theory paper) is a required read, and the CUCVElectric thing is a good thing for troubleshooting.

Thanks for correcting me, I re-read it myself.

Will

 

[TCUCV]

I don't know of a "Glow Plug Switch" listed in the manual. Can you reference which TM and page?

In any event I do not believe it is the same as the glow plug temperature sensor. The temperature sensor is mounted on the top rear left side of the head, and has 2-wires running to it. Remove the air cleaner and you'll see it.

Its in the -20 manual for the M1008 . . . page 193

Chapter 3-20 "Glow Plug and Glow Plug Switch Replacement"

It seems to be exactly what you described

 

[GPrez]

Its in the -20 manual for the M1008 . . . page 193

Chapter 3-20 "Glow Plug and Glow Plug Switch Replacement"

It seems to be exactly what you described

I think your right. I believe they are one and the same.

 

[Barrman]

I really don't think the glow plugs are your main problem. A healthy 6.2 should fire up in less than 1 or 2 seconds. That is cold with a proper glow plug system or anytime it has been sitting after being run without the glow plugs coming on.

I would suggest a starter motor check, battery load check, starter wiring check and as mentioned already. A healthy injection pump of course is a must.

My first 1009 took 5-12 seconds to start. I thought that was normal since it was my first 6.2 experience. Then, I cleaned the glow plug card so that system actually worked which brought cold starts down to 5-6 seconds. Hot starts were about the same. Then, my starter motor burned up along with one of my batteries. A rebuilt starter and a pair of fresh batteries had the motor spinning so fast I couldn't believe it.

I also had installed a spin on air filter about this time.

Starts happened faster than I could let go of the key hot or cold from then on for the next year or so. About the time starts started getting slower is again is when my IP started leaking all the time. A new IP and super fast starts have been the norm ever since. This includes my wife daily driving it for 8 months.

To sum up, I don't think you are looking for a single problem. Getting these trucks up and running is a total system effort. But, once you do all that is needed. Many years of trouble free driving will be in your future.

 

[cshaw07]

I didn't know about the check valve on top of the IP, ill pull it and check/clean it when i get home tonight. Last night I installed my spin on filter and pulled the GP temp sender from the engine, plugged the hole, and just left it lay on top of the motor plugged in. I planned on driving it around to test my theory (i have a new temp sender thing in the mail from cucvelectric) but my rear battery was too dead for it to start and my neighbor wasn't home with with his battery charger, i really need to buy one... The rebuild kit for my alternator isn't in yet either, hopefully it gets here today though! I feel like I am so close i can taste it, ill let you all know what i find out tonight. If it still doesn't start when its warm, but will after i pour water on it, it means i have a bad IP right?

 

[ralbelt]

Barrman is this a new type of mod? "I also had installed a spin on air filter about this time."

 

[Warthog]

...but will after i pour water on it, it means i have a bad IP right?

No it means the fuel shutoff coil on top of the IP is going bad. About $20 on fleebay. Your Stanadyne dealer will have them also.

 

[cshaw07]

awesome. i don't think my IP is going bad, i see no fuel leaking, it holds idle strong, and has power like it should, runs smoothly and doesn't smoke much after a few seconds after start up. there is 28k miles on this truck, i don't know if that's good or bad yet though. who knows how long shes sat around.

 

[Barrman]

Yes, the spin on air filter is mentioned in the 5th update to the -20. You don't have that version?

That is what I get for trying to watch tv, talk to my son and listen to my wife while I am on the computer. Sorry.

Back to the original problem. The more you post, the more it seems you just need to start over. By that I mean go to the troubleshooting section of the -20. The first thing it says you have to have is fully charged batteries that have been load tested. Once you have that done, put all the pieces back together and see what happens. Then, follow what the manual tells you to do based on symptoms.

 

[cshaw07]

Brand new 850 CCA batteries, brand new terminals, all wiring has been cleaned and greased, tested glow plugs all are 1.4 OHM and all get 10.5-12V while WAIT light is on, 12V resistor bypass, new solenoid, GP temp sender on order, driver side alternator is working (got one from autozone) passanger side is not working as i am waiting on a rebuild kit. Until i get the alt rebuild kit i put the passanger side battery on a charger to keep it charged. I put the spin on filter on to rule out leaks there and changed all the rubber vac/fuel line with new including the one under the truck. I feel like i am getting there, i just looked over the -20 troubleshooting manual and I've done about everything its said to do. I should know tonight if she's fixed or not. I just found out that my rebuild kit comes in tomorrow and not tonight though.

 

[cshaw07]

Its fixed! Not sure if it was the glow plugs not cycling when warm or the spin on fuel filter i just put on, but it starts warm, cold, hot or anything in between. Now, when i get my alternator kit in and get that working it will be DD ready then time for the lift and 37's! Thanks guys!