97 psd alternator?

[MUDWHISTLE]

When I start mine up when its cold (before its been run for the day) The amp gauge stays at the low mark for about two or three minutes, and is not charging, but when this is happening I have checked my alternator with a current meter and is supplying around 50 amps. after the few minutes the light get brighter and the gauge moves to the normal position and it is fine and never dips again until the engine has been shut off for a few hours and restarted. it has never caused a problem and has done this for over 2 years. what do yall think?

 

[95_stroker]

That is the glow plug cycle. When the relay is active it really draws down the system.

 

[MUDWHISTLE]

I thought that they cycled on and off, do the glow plugs stay on consistantly for that three minutes?

 

[95_stroker]

On a fresh start, the GP circuit is active for as long as your volt meter is draw down like you are explaining. I dont know off the top of my head what the duration is. I thought some of the PCM's used the IAT or EOT sensors to regulate the GP cycle lenght. But rest assured that what you are seeing is the GP cycle.

 

[MUDWHISTLE]

Yeah I did not think it was anything serious since it had not caused a problem. Nice ride by the way wish mine was a crew cab.

 

[Crumm]

But rest assured that what you are seeing is the GP cycle.

Yeah what he said

 

[95_stroker]

Yeah what he said

Didnt the 97's PCM vary the cycle time based on either IAT or EOT sensor info Crumm?

 

[Crumm]

Yeah. The stock programming in my 96' just turned the plugs on for a set time. When I upgraded the programming to the latest and greatest that came out in 97' the plugs started cycling for a shorter period of time depending on the temp. When the truck is parked in the shop they are on for a short time, when I am parked outside at -40 they stay on for a long time. I don't think they ever actually cycle they just come on and when they are done they turn off and never come on again until the next start-up.

 

[95_stroker]

I don't think they ever actually cycle they just come on and when they are done they turn off and never come on again until the next start-up.

Agreed, maybe my terminology "cycle time" is incorrect. I refer to coming on, doing their duty and subsequently shutting off as a cycle.

 

[JOAT]

When I start mine up when its cold (before its been run for the day) The amp gauge stays at the low mark for about two or three minutes, and is not charging....?

Strangely, my Amp gauge exhibits similar behavior even with my GPR disconnected, tho not as low of a reading as when the GP's were being used. Maybe part of it is due to the initial battery recharge