PDA

View Full Version : Cold idle



BigGun J
02-22-2008, 21:37
93 C2500 4L80E. Turn the key to on, while waiting with the glow light I push the skinny pedal to the floor to set the cold idal. After the glows time out I hit the start and vroom wakes right up. I need to bring the RPM above 1K and then let off for it to idle at cold set? My 93 Ford 7.3 will set by pushing the pedal to the floor with the key on. Is the 6.5TD to do the same? After a bit of idle it drops out of cold idle. It is no problem to give it a bit of pedal after it starts but, I thought it should set on its own if the key was on and you pushed the pedal to floor and let up before turning the key to start?

PS, have had no more bubbles in the coolant and it seems to be holding the line!!!!

I sure like driving this truck!

Jim

DmaxMaverick
02-22-2008, 21:43
Your 95 is EFI, and should not require any pedal to start it and engage the cold advance/idle. If if does, something's wrong. Your 93 Ford was mechanical, and did require a step on the pedal to get the high idle to engage, as did the mechanical GM's.

a5150nut
02-22-2008, 22:26
Dmax, look again. He said 93.............

DmaxMaverick
02-22-2008, 23:22
:D

too far from my spectacles....

All good, except that part about "your 95" and that EFI stuff....

The high idle should set with key on and pedal pressure. The HPCA (cold engine timing advance) should set w/o pedal pressure. The high idle solenoid could be losing power (or enough to hold it) during a cranking cycle. If it holds after started, it's working. If you apply slight pedal during start, it should keep the high idle until the HPCA disengages. If you are having issues with this, it's probably a poor ground or dirty connection. Could be just about anywhere in the system. Battery(ies) on their way south could do the same.

daustin
02-23-2008, 10:01
My '93 sets the high idle only if i step on the pedal when in run/wait to start while it's getting the glows on. I think that's normal with the mechanical IP engines.
Don

BigGun J
02-23-2008, 21:47
It will not set prior to start. It is no big deal to give it a bit of RPM after start to set the idel. On another note. I have a small 21 foot sail boat "maybe 2K with trailor" and took it to the lake today. the truck was sure happy pulling it. I was sure happy being able to feather the throttle in my yard and not leave a single spinning tire trail as would have happend withe the Ford.

Jim

bobt
02-23-2008, 23:17
I just checked the start instructions on the visor of my '93 (yep, they're still there). Step #1 says "Turn ignition key to the run position then depress accelerator fully and release."
Bob