91 IDI glow plug issue help please
 

I volunteered to work on an old IDI....first time ever on one of these cats, anyway it runs just fine but he says it doesnt start without starting fluid, its in my shop now so I pulled the aircleaner to get good view of things, I turned the key on to activate the glow plugs and the module behind the intake ontop the motor is clicking in and out terrible, this is the realay that feeds power to the glowplugs maybe??????? So I cleaned up all the battery terms as they were all corroded but the module still clicks like crazy

guide me straight here men

if it is clicking alot, probly has some glowplugs burnt up. test restance in each glowplug. unplug the harness and test. another quick test but not always correct is to use a test light, hook the dumb end to the + batt and use the needle ant test plugs, if it light, plug is probly good.

it is clicking due to not enough restance there probly.

OK...............I will look into that bro

What dieselcrawler said, bad plugs cause resistance which is what the controller senses to determine how long the plugs should be on. I would get a new set of motorcraft glow plugs, avoid other brands unless you enjoy changing plugs. The solid state controllers on the 7.3 dont fail very often, so a new set of plugs will usually get you going again.

its goin.........all glowplugs showed bad so I went to town and got 8 new ones for 8.90 each so it wasnt bad.......they were motorcraft to just by chance

thanks for the help men:c:

no prob whit.

Awesome, dang good price for MC plugs too. :tu:

i recognise that name. i belive he is also over on thedieselstop.

he is a mod from oilburners, old and dear friend

i am posting this for anybody that has already changed glow plugs or is going to change glow plugs in the old IDI. DO NOT USE AUTOLIGHT...the ends of the glow plugs swell up usually causing them to break when they are being taken out to be replaced. Plus, you do not get that much use out of them. My body changes his once a year and uses the autolight. I tried to tell him to use either motorcraft or bosch. I have been running the same set of bosch glow plugs for 2 years without any trouble and there is only a very little bit of difference in price.