"Glow Plugs" light flashing

[ShawnR]

6.2 to 6.5 block swap out is done, timing appears to be set and all if good.

Glow plugs light comes on as normal on a cold start, stays on for probably 12-15 seconds, start truck, wait a few minutes & drive away.

After the truck is completely warmed up and I am at cruising speed, the Glow Plug light flashes for about 1/2 of a second evey six seconds like clockwork.

I can do the one one thousand, two one thousand,...up to six and at the end of six it flashes for half a second. It did it consistently for several minutes. (I was watching it insead of the road). It only seems to do it while driving, not while sitting at idle.

I recently swapped long blocks and all sensors. The GP controller stayed with the truck and the rest of the wiring so it shouldn't have been damaged, but anything is possible.

Any thoughts? The truck is a 93 so it has minimal computer controlled stuff.

 

[Turbine Doc]

CTS bad or not connected, PCM doesn't know engine is hot, would also impact your starting, as TSM/cold advance looks at coolant temp just like glow control, that would be a viable cause of your other issues.

 

[ShawnR]

CTS is the one on the crossover to the right of the injection pump?

 

[chrisk1500]

Does 93 have the inhibit switch or the ECT sensor.....or both?

 

[ShawnR]

Does 93 have the inhibit switch or the ECT sensor.....or both?

Feel free to just imagine me sitting here with a dumb look on my face not knowing at all what you are referring to. What are both of those and what do they do?

I am thinking that this is the CTS switch that Tim was referring to.

 

[chrisk1500]

That is the ECT (CTS) switch/sensor...looks a touch on the broken side of things....and obviously not plugged in....

 

[ShawnR]

That is the ECT (CTS) switch/sensor...looks a touch on the broken side of things....and obviously not plugged in....

Actually, that was when the engine was out of the truck. I took LOTS of pics for details of when to put things back together. The way that brackets fit on and such. I'll just replace it and see if that fixes things. It can't be that expensive.