Question1996 Disco I, 187,000 miles, GEMs 4.0
Driven occasionally – used to be a daily driver when gas was $1.70, but now it’s driven to tow the boat, go to Home Depot, as an emergency back-up car.
Recently I’ve started having issues starting the engine when it’s warm. The engine starts, but then the RPMs oscillate between 500 RPMs (almost stalling), and about 1000-1200 RPMs.
A couple of days ago, 80 degreesF outside, I towed a 2500 lb boat and trailer about 40 miles. When going up a 2 mile long, 20% grade, in 3rd gear, the engine temperature started going to the top end of the normal range; it’s never done that before. After cresting, the engine took a while to cool back down to the lower end of the normal temp range. When I got home, it hood was downright scortching. I tried to restart, and didn’t hear anything (no starter, no solenoid, no clicking – but I did get dash lights). After a few turns of the key back and forth, and I heard an electric fan come on under the hood. After about 10 minutes of the fan blowing, it went off, and the car would at least engage the starter, but the engine wouldn’t catch, though it was trying. After a further 30 minuets with the hood up to supplement cool-down, the engine fired right up.
Recently, I had the corroded tranny cooler lines replaced – don’t know if I had any starting when warm trouble immediately afterward (maybe the mechanic inadvertently did some wire damage), or if where the mechanic worked was anywhere near the sensors so risk was minimal
I’ve read some forums that equally say that I have a fuel temp sensor issue, or a coolant temp sensor issue (sensor, connector corrosion, etc.).
I could definitely use advice on which sensor (or if it’s something else entirely), how to check, and where it’s located.
Thanks
AnswerFuel or engine temp sensors could keep your truck from starting, as could a cam or crank sensor. In the absence of testing, you are just making guesses and changing parts. I would suggest getting the factory workshop manual and testing each of those sensors at a point where the truck is failing to run.
I think the issues of failing to crank and failing to start represent two separate problems. I would suggest you give priority to solving the problem of engine overheating, as that will ruin your motor if it continues.
The connection between all the problems is that they may be heat related. In other words, you may have several components under the hood that act up when they get too hot.
If you heard the fan that says the electric fans are working sometimes. If the temp gauge in the truck reaches 3/4 the fans should come on when it's running. If not, there is a circuit problem to be traced. There are some longer articles on Land Rover overheating on the Robison Service website. You may find those useful
