M1008 glow plugs don’t stay on

[Kool-Aid Kid]

Glow plugs only power up for a split second. I have installed a new controller card and relay turn the key on and you can hear the relay cycling but it will only power up the glow plugs for a split second at a time any help would be appreciated

 

[richingalveston]

the temp sending unit to the glow plug card is probably bad. your card may be working properly but if the temp sending unit (which I believe is in the back of the passenger side head) is bad, the glow plug card thinks your engine is already warm.
check the sending unit. I think there is a method for testing this sensor in the TM's but do not know for sure.

 

[dougco1]

Actually the temp sender for the glow plugs is driver side rear top of engine. The one on the back of the passenger's side head is for the high idle kick down.

 

[cucvrus]

Check your glow plugs also. they could be all bad and it is sensing it thru the glow plug controller. Also the relay could be going bad under the hood. Hard to diagnose from afar. Good Luck. report back.