Yet more Glow Plug Troubleshooting - 1992 F250 IDI
OK, I have been limping along with no functional GP system for a couple of years and have finally decided to fix this if it kills me.
Today I have just replaced the GP controller and solenoid with a brand new unit from NAPA. I know this is good. The harness from the controller to each GP was replaced as well. I ohmed each GP, and each of them reads between 0.6 and 1.0 ohms. COntroller is grounded all the way back to the battery.
I ran a jumper from the battery to the small terminal that energizes the solenoid, and the the solenoid cycles about once/second. Glow plugs are not getting hot.
Any idea what could be causing this? Batteries are a little weak, but they still crank the engine. I don't think it is the batteries.
I read somewhere else that the plugs should ohm at 0.6 to 2.0 ohms. Is the fact that all of them are down around 0.6 enough resistance to make the controller cycle like this? Glow plugs are the only thing left to replace, but I wanted a second opinion before I spend another $100 on a set when they appear to be OK.
1992 F250 S/C XLT
7.3L IDI, 5 SPD
Bought it brand new in 1992. Fisher-Vincent Ford in Belton, TX
Last edited by Burdizzo; 02-27-2010 at 03:04 PM.