Do the 2004 Discoveries have a grounding strap connecting a head to the body of the car? If so, I might have lost it or it was missing. Will the car start with it missing?

 

You need every ground strap or an equivalent. Even if it starts, not having it is sure to cause you issues.

 

I think the head ground strap was on 2002 and earlier vehicles. A quick search here might find the thread.

 

Both my 2003 and 2004 have a grounding strap from one head to one of the bolts holding the heat shielding to the firewall. I made a second one for my 2003 to try and suppress some noise that was coming through the radio.

 

Max current goes through the starter, so best to have a direct ground from the starter to the battery (or near the battery). Also best to have a heavy duty ground from the alternator to the battery. If you have those, an extra ground strap is icing on the cake, but cake is fine without icing. Main principle is the engine sensors need a good reference ground to the ECM.

If the starter ground becomes open or corroded or loose, the current will find the path of least resistance, so some have burned up the E-brake cable that way.

 

Yeah, uh, all years of DIIs had the grounding strap connected from the rear of the Bank 1 head to the firewall. Your truck may start without it, but there'll be hell to pay down the road if it or some substitute is not in place.

It doesn't need to be the original, braided strap. A short battery cable will do the job too. Just don't kid yourself that it wasn't there or it isn't important.

 

Damn better check mine then.

 

My 04 D2 has two grounding straps: one smaller on the drivers side to the firewall and one bigger on the passenger side to the body near the battery. If only the front one near the battery is not making good contact, the starter motor struggles to start the engine and battery won't charge well.