Can IDI engines start just fine in winter if everything is in check, like the glow plugs and injectors?
If well maintained, they start just fine.
Make sure the glow plug harness is in good shape (I made a new one with thicker wire), check the relay, and always use genuine OEM glow plugs. Aftermarket ones can burn out and break off into the cylinder.
Strong, healthy batteries and a good starter help a lot too.
@Micah
It’s amazing how well these engines run when properly maintained. It’s the ones that are poorly maintained that give them a bad reputation. Also, Ford’s wiring is a bit of a headache sometimes, it’s a wonder more of these engines didn’t end up failing badly.
I added a momentary switch to my glow plug relay, and it works great for me. But my winter temps rarely drop below the 20s.
It can be tough to start if the glow plugs and their controller or harness aren’t in top condition. The system is known for melting the harness at the connectors, and the controller can fail too.
Also, air in the injector lines can cause issues. The return line caps and O-rings can let air in, which means the injectors don’t get the right fuel pressure to open properly.
Another issue is the cold idle advance solenoid. If it doesn’t work, or the sensor that tells it when it’s cold is bad, it can affect starting. The sensor for the solenoid is separate from the one that controls the dash gauge, so the gauge might show a normal temp while the solenoid isn’t working.
But if everything is working well, IDI engines should start fine in the cold.
It seems like your 2000 model would actually be a Powerstroke, not an IDI. Two different but very solid engines.
Vesper said:
It seems like your 2000 model would actually be a Powerstroke, not an IDI. Two different but very solid engines.
You’re right! The Powerstroke is a different engine, but still great.
My 86 6.9 started after about 30 seconds of cranking this morning at around -20°C.
I have the higher watt heater in my 7.3 IDI. I usually block the radiator and try not to use the glow plugs, but I’ve started it at 5°F without them. The glow plugs do work, but the engine holds heat pretty well. If it’s really cold, I’ll start it during breaks and keep enough heat to barely need the glow plugs during the day.
With good rings, the engine can get enough compression to start without the plugs at 65-70°F.
Switching to 5w-40 diesel oil makes a big difference compared to 15w-40.
Emil said:
Switching to 5w-40 diesel oil makes a big difference compared to 15w-40.
0w-40 works even better in colder temps.
They can be hard to start in the summer if the glow plugs aren’t working. If your glow plugs are in good shape, along with a good starter, batteries, and fuel system, it should start fine. I had a bad lift pump once, and that made starting a bit tough. Even with that issue, I could get it to start fine with a block heater.
Mine starts fine at 30°F without glow plugs. I do have to bleed the air out of the fuel lines though.
Either make sure the glow plugs, harness, and controller are in good condition, or just pull them and use ether to start the engine.