Its as if something like the old Chevy automatic choke was stuck in the open position. My 2000 7.3 liter F350 won't start cold unless engine warmer is plugged in. Have been to Autozone to read codes but by the time I get there it is warmwed up and tech there says it wont register if problem is not occurring then. HELP!!!!!!!!!!!!

 

has to be first start of the day, my 2000 f250 7.3 does the same day, once you start it once its good the rest of the day. was told cold be the glow plugs. getting mine replaced for a diesel rx kit this summer

 

A good portion of the time this problem is corrected by replacing the glow plug relay.

 

OK thanks. Boy amI getting lots of 'could be's'. It is boiling down to cost of repairs. Fuel injectors, glow plugs, control modules, etc. is there any quick test of injectors?

 

Replace the glow plugs instead of repairing them. Also, you can try cleaning the fuel injector using cleaner fluids. To test the fuel injector, use pressure test.

 

If the engine runs fine once started, don't waste your money on injector cleaners etc.
The simplest thing to do is replace the relay, it's right on top of the engine with the terminals on top. That is a common problem with the 7.3 .
Even if you had one or two bad glow plugs the engine would manage to start cold.`None of the glow plugs can work if the relay doesn't work first.

 

Hanky's pointing you in a good direction.

Sometimes the glow relay will bulge out, or the copper lugs will be discolored from heat if it is failing/failed. If it is good, you can also try and unplug the EOT sensor (engine oil temp) and it will cause the glow system to default to 2 minutes of ON time. (will set a DTC/CEL) Don't know what temps your trying to start up in (?) but unless it's pretty cold usually they will start with some extended cranking,, but depends on 'how cold'.

But as already mentioned, the glow system including the relay for activation should be checked to take it 'out' of the cold start diagnosis. If you have a DVOM meter? (volt ohm meter) we can give some quick check test to prove out the glow system operation as well as the glow plugs for integrity without replacing good parts . If the truck starts easily when plugged in, and idles 'stable' on startup when/while cold, then again I'd look at the glow control items.