Any error codes. Have you taken a plug out to see if there is any spark

 

I found the non start issue. Bad fuse. I thought that I had checked every fuse in the engine bay fuse box. I must have missed one. 15 amp on the fender side of the fuse box. Swapped it out and engine started right up! That is the good news, the bad news is that the voltage issues remain.

It was showing 13.4 the using the gap tool. 13.4 using battery terminals and 14.75 using battery positive and grounding to engine block. Took it out on a spirited drive on the freeway. About twenty miles. Voltage dropped from 13.4 to 13/13.1 for the first few miles. It dropped to 12.6 - 12.7 and the to a low of 12.4 for several miles. Cooler box shut off. I didn’t notice any transmission issues. As I got off the freeway and came to a stop at the exit, voltage jumped to 13.1. It stayed there for the three miles drive to my house. Parked and running in the driveway the voltage rose to 13.4 and then slowly changed from 13.2 to 13.6. Usually sticking around 13.2. Cooler box turned on. Everything was working.

I turned the truck on several times. It started right up on each but one attempt. On that incident it started up but took a bit longer to fire up. (Fuel pump seems to be working,I can hear it kick on and there is fuel at the rails).

It it is so strange, voltage drops on the freeway and went back up once I pulled off and drove on city streets. (Last week when grounded to the engine block, the voltage dropped after I got off the freeway).
i must have an open circuit or a bad ground somewhere.

Scratching my my head in San Diego.

Phil

2006 Range Rover Sport HSE 46,000 miles.

 

Update - I took the RRS over to The British Garage here in San Diego. They had worked on the truck a few times in the past. When I got there, they were swamped with work and too few techs. The one tech that had worked on the truck before told me that he wasn't really excited about tracking down ground fault issues and suggested an auto electric shop in the same strip mall. I dropped the RRS at the electric shop last week. I got a call today. They told me that they thought that the problem had been solved. It was a combination of issues, including some loose retaining clips on the engine fuse box, a fan near the ecu that had shorted and a faulty ground at the fender on the passenger side, it looked good on the surface, but had been repaired before I got the truck when the prior owner hit a snow bank. I will get a more detailed report when I pick up the truck. He also thinks that it took care of the "slow to fire up" issue. He ran two new ground cables, one to the fender and one to the engine block. keeping those fingers crossed! All for less than $500. Phil

 

Success!

I picked up the 2006 Range Rover Sport with the electrical issues. Looks like the shop got it resolved. Original owner hit a snow bank after 9 months of purchasing new from the dealer in Indiana with only 15,000 miles. Original owner bought a new Range Rover and left the RRS at the dealership. A guy here in San Diego knew the manager at the dealer. They cut a deal for the RRS. Truck was shipped to San Diego and repair were made, but not completed. Project was interrupted and the truck sat in a state of mid-repair for 7 years. That is when I bought the truck.

The right front fender and inner liner had been replaced. The ground post on the inner liner had evidently not been properly secured. That post failed. That was what causing most, but not all of the electrical issues. A new ground post was installed. In addition, the shop ran a second ground to the engine block. There were also several loose fuse female clips in the engine bay fuse box. Those were fixed. The shop also told me that there was an "after market" fan behind the ecu that was not wired correctly. I still am not sure exactly what that was. I never installed any auxiliary ecu fan. They said it was drawing power but that it wasn't grounded,

Issues resolved:

Voltage is now consistent, getting at least 13.5, usually higher at the dash per the Gap Tool readings. Voltage at battery 14 or higher.
Engine starts right up, no longer have the long crank, not start issue, (seemed like a fuel pump issue)
Transmission is smooth again. No hiccups, no bucking.
Cooler Box is working at all times, very important.
No codes that can't be explained. I still have a right front headlight module fault, a engine fan 3 fault, and a ventilation driver's side floor actuator fault, had all of those before the electrical issues arose.


Life is good again. Hope that this journey will be helpful if this happens to your truck. Electrical issues can be a bugger. A huge thank you to all of you whom have offered input.

Phil

 

Thanks for posting, amazing what problems an intermittent earth can cause. Enjoy your ride.

 

Two Week update. The Range Rover Sport is running great. Drives like new again! Transmission is flawless again, the cooler box works.

A quick aside, we drove the 2010 Range Rover Sport to Utah and back last week. Range Rover Sport ran beautifully. It was like driving on rails, smooth and straight. Averaged 19.4 mpg overall for 2,000 miles. Speed limit in Utah is 80 mph. Traffic actually runs around 85 mph, same for most of Nevada. Audio control unit is on the fritz, so no radio, took a small bluetooth speaker and listened to Pandora and Podcasts up and back. Not exactly hi fidelity, but it worked. (I had been having a suspension fault for the last month or two in the 2010 Range Rover Sport, the run to Utah and back has cleared the code and the "suspension of special features" notice).

When these trucks run, they are incredible............