[NCC74656]

is 81psi at cold idle to high? my truck starts there and falls to 38psi at idle when warm.

its gotten a bit chilly here and ive started to notice it a bit harder to crank and more white smoke. my "wait to start" light has not come on yet. what type of diagnostic can i do to test this with out needing to make the engine colder?

thanks.

 

[dozer12216]

Real gauge pressure I assume.That is O"K. Synthetic might help lower some when cold.

 

[NCC74656]

yes, real gauge. i run rotella 15W-40 but now that i think about it i dont know if i chose trippleT or T6...

 

[NCC74656]

it hit about 30F day before yesterday and no wait to start light, it was cold enough to produce just a little bit of white smoke but not a lot. the fuses are all good for the grid heater so maybe its just not cold enough yet.

 

[tylerallout]

Are you saying that your wait to start light isn't coming on at all or it just isn't longer than the normal bulb check when you turn the key on? Your grid heaters should have come on by now and the wait to start light should be staying on for quite a while by now. I forgot at what temp they actually come on but I know mine do when it is in the 40's.

 

[NCC74656]

no light and no heating

 

[me78569]

at 30 your wts should stay on for at least a few seconds.


Any codes?

 

[NCC74656]

can i force that circuit to close to test it?

 

[me78569]

no the ecm tells the grids to cycle,


pretty sure the grid heater relays will throw a code if they dont open.

Typically if you don't have a WTS then your ecm is dying.

 

[tylerallout]

You can jump the relays for the grid heaters but they probably work just fine, not sure about doing anything else. I think the wait to start light is an LED so it probably isn't bad. I'm afraid to say that I think your ECM might be going bad.

 

[NCC74656]

the ECM has self diags on it right? if an ECM goes bad i would assume other would go wrong and the WTS would be the least of my problems. seems strange only one function would go bad?

if everything but the WTS works then i suppose i dont care, ill just delete the heater and call it a day.

 

[me78569]

wts not working is the first thing that typically happens, then shortly after you can be left on the side of the road.

Consider it the p0216 of the ecm

you will typically get codes also.

 

[NCC74656]

just did a google of ecms, 650 going rate? my pcm was like 120 at a scrap yard.

well ill run with it and see what happens, what all does that control? if the truck is on and it goes out does it shut off or will it stay running?

 

[tylerallout]

you might get lucky and it stay working for a while. It controls everything to do with the engine, if it dies your truck shut off. You'll need to make sure that the part number on it matches the part number on your ecm because there are some differences in the years.

 

[bigfish95971]

What is your volt meter doing right after start up? Even at 30 and not waiting for heaters it should start in less than half a crank of the engine. Have your batteries load tested. If any weakness in either, replace both.

 

[NCC74656]

ill double check tomorrow but i think its staying at 13V. the batteries are good but they are not always fully charged. my drive to work is rather short and my radio pulls about the same as my at is producing i think. the batteries stay charged if i dont blast the music but do not remain charged when its turned loud and i dont drive long enough. i will need to install a second alternator i think.

 

[cummins6sp5.9]

You LOUDNESS has ZER afects with hoe or if thr batteries stay charged. If your sound system is pulling more juice then what your altenator puts out then you have to choose which is more important. Your ECM $2K+ OR YOUR MUSIC @ ?????!!!!!!

 

[bigfish95971]

Your alt should be putting out 14+ volts. The grid heaters will make the gauge go down and up from 8 or 10 v to 14 when cycling, if operating. Completely disconnect the amps at the battery for a week, dirve it for an hour and then see what happens over a week or so.

 

[tylerallout]

If the wait to start light is not coming on right now the damage is already done.
I doubt that the sound system had anything to do with the demise of his ECM but maybe.

I would be checking to see whether the alternator is putting out any AC ripple with both the sound system off and cranked up to see if there is any. The ECM seems to be extremely sensitive to noise.

 

[bigfish95971]

Try this and get back to us. Turn the key to on, not all the way to start, and wait for about 10 to 20 seconds. Watch dash for the wait to start light to come on for a few seconds. If if comes on go ahead and finish turning to start with out turning back. Should then start right off. Report back.