glow plug relay question

[mustangmatt89]

my 93 7.3 is not acting the same way, when I turn the key to the on position the glow plugs are not cycling as long as they use too, they are new plugs too, it still starts but requires more crankin, also there are many clicks afterwards and there is an extra wire run to a switch under the dash from it, but not hooked up any more, I am thinking I should replace the relay module what you all think? Oh and it has new glow plugs less then 1000 miles ago

 

[Jake S.]

What kind of plugs did you put in? I had a 7.3 i was working on with champions in it and it started hard. But beru's (motorcraft's) in and the wts light stayed on 5 sec. longer.

 

[mustangmatt89]

Well I am not sure the shop I was using at the time put them in. Maybe I will just put new glowplugs and the relay in.

 

[Agnem]

Measure the voltage drop across the big lugs of the GPR when it is engergized (glow plugs on). You should have very close to zero volts. If it is higher, then you have burned or pitted contacts and the relay should be replaced.

 

[mustangmatt89]

well I couldn't ge it started this morning... Glow plug would only come on for maybe 2 seconds and cut off, I plugged it in and left for work when I got back it started right up with it plugged in, I ordered new glowplugs today and relay from ford, could anything else be causing this, besides those 2

 

[Jake S.]

Here are some of the common problems with the newer (87-94) system. If your wts light is on for a short time, the plugs usually are bad. Have to test them and change the bad ones. Berus are my pref. Second, the relay on the controller also fails and causes either no voltage or a lower that battery voltage to go to the plugs. If there is 12 volts on the battery side, and less than that on the other big terminal with the flat bent up piece with the wts on, the relay is bad. Lastly the engine connector that is by the fuel filter/passenger fender well likes to melt. The connectors get dirty for the wires going to the glow relay. A good solution for this is to run your own wire instead. Like a single 8 gauge wire.

 

[mustangmatt89]

Thanks Jake if I will also look into that once I get my parts in tomorrow from ford tommorrow and install them

 

[mustangmatt89]

I replaced the solenoid nothing, I pulled a plug and they were auto lights, so I was able to get 3 beru I bought in the engine was still got so I couldn't get the others but the light is on much longer now, I guess I will be changing all the plugs tomorrow night

 

[Agnem]

Did you bother to do the test I gave you before you replaced the solenoid? Why torture yourself guessing....

 

[mustangmatt89]

yes I did the solenoid test i think it would not have kept it from starting but would have eventually so I replaced any ways, but I started replacing gp and that helped amazing although they are new plugs but they were autolights not beru, starts like new again.

 

[Agnem]

Fair enough. The 7.3 system depends heavily on 8 functioning glow plugs, or it just won't cycle right.