MountainD
Technical Excellence Contributor
Intermittant issues are the WORST! I remember someone convinced me a fuel pump was either good or bad and never intermittent. Finally when I got around to replacing tons of parts with seemingly intermittent success, I replaced it— but not before accumulating a ton of spare parts and tons of wasted time. But finally, success. For 3 days. Fuck. Fuel pumps are the worst part imho to change out. But wasn’t it. (And yes, the ABSOLUTELY can be intermittent as that has also happened to me). My point is that I was randomly replacing and buying parts that I thought were suspect for no other reason than a guess. There are tests for just about everything, but when it’s intermittent it compounds the difficulty. The fact that it won’t start after it dies gives you a great opportunity for some quick trouble shooting to try and solve it.
Ive been breaking down in rovers for 2 decades and I’ve spent a lot of money on random parts and then invested a lot less on a few troubleshooting tools. I now try and change only what I know is wrong, although I admit I’ve still made mistakes. a good multimeter is the cheapest and most helpful tool I have. But I also have a fuel pressure tester, a block tester (fluid is a must, but I also have a leak down tester), Cylinder pressure tester, an in-line spark plug tester and a workshop manual and a 14CUx diagnostic manual. Best, and most important to all, I know basic systems and how to go about diagnosing them.
This is a great resource: http://www.britishv8.org/articles/rover-14cux-efi.htm
This also has good info: https://landroverforums.com/forum/a...nagement-manual-1314cu_14cux_systems-info.pdf
This one has helped me on my RRC to learn how to diagnose components: https://www.landroverweb.com/Pdf-files/Manuals/Range-Rover-Manual-Fuel-Injection.pdf. (Your model may vary—not sure your year).
get the free rovegauge software and make a cable. This takes about it: https://discoweb.org/index.php?threads/14cux-diagnostic-software-libcomm14cux-rovergauge.79207/
i learned the difference between “its gotta be the...” and “it is...”
in the above situation, it was my ignition switch which separated causing intermittent random power loss, but I’ve also had a similar instance where the truck would idle fine and then die if I gave it gas. I replaced everything, finally convincing myself it was the cam, and changed it out. It wasn’t. That turned out to be a small white plastic washer/spacer thing under the rotor in the distributor had disintegrated.
Compression, spark, fuel.
something is out of spec. When it isn’t starting be ready to check spark (I always start there). Toss an in-line spark checker ($10) and learn the difference between a weak spark and a strong spark. Know how to diagnose your coil and check the voltage both under ignition on and ignition start conditions (diagnoses switch). Know how to use an inline fuel pressure checker on the fuel rail (or better yet if you have a Shrader valve on the rail!) and know your operating pressures. With those three 5 minutes tests, you have narrowed down significantly on where to check next. know how to check for vacuum leaks, timing issues, etc. nothing on these trucks is that hard to figure out.
There are tests for every component that I know of. Come Up with a routine of process of elimination— start big and narrow down. As you go, learn what components also DO. Try and find info on symptoms of a failed fuel temp sensor, coolant sensor, whatever. Can I put it in a limp mode, does that help? Try and learn the function and the test— it will help a ton! If you are confused on how to test something, just ask, but try and read up a little first. The above links will help. Personally I hate 13CU/14CU/14CUX systems— I’ve spent way too much time on them, lol.
Ive been breaking down in rovers for 2 decades and I’ve spent a lot of money on random parts and then invested a lot less on a few troubleshooting tools. I now try and change only what I know is wrong, although I admit I’ve still made mistakes. a good multimeter is the cheapest and most helpful tool I have. But I also have a fuel pressure tester, a block tester (fluid is a must, but I also have a leak down tester), Cylinder pressure tester, an in-line spark plug tester and a workshop manual and a 14CUx diagnostic manual. Best, and most important to all, I know basic systems and how to go about diagnosing them.
This is a great resource: http://www.britishv8.org/articles/rover-14cux-efi.htm
This also has good info: https://landroverforums.com/forum/a...nagement-manual-1314cu_14cux_systems-info.pdf
This one has helped me on my RRC to learn how to diagnose components: https://www.landroverweb.com/Pdf-files/Manuals/Range-Rover-Manual-Fuel-Injection.pdf. (Your model may vary—not sure your year).
get the free rovegauge software and make a cable. This takes about it: https://discoweb.org/index.php?threads/14cux-diagnostic-software-libcomm14cux-rovergauge.79207/
i learned the difference between “its gotta be the...” and “it is...”
in the above situation, it was my ignition switch which separated causing intermittent random power loss, but I’ve also had a similar instance where the truck would idle fine and then die if I gave it gas. I replaced everything, finally convincing myself it was the cam, and changed it out. It wasn’t. That turned out to be a small white plastic washer/spacer thing under the rotor in the distributor had disintegrated.
Compression, spark, fuel.
something is out of spec. When it isn’t starting be ready to check spark (I always start there). Toss an in-line spark checker ($10) and learn the difference between a weak spark and a strong spark. Know how to diagnose your coil and check the voltage both under ignition on and ignition start conditions (diagnoses switch). Know how to use an inline fuel pressure checker on the fuel rail (or better yet if you have a Shrader valve on the rail!) and know your operating pressures. With those three 5 minutes tests, you have narrowed down significantly on where to check next. know how to check for vacuum leaks, timing issues, etc. nothing on these trucks is that hard to figure out.
There are tests for every component that I know of. Come Up with a routine of process of elimination— start big and narrow down. As you go, learn what components also DO. Try and find info on symptoms of a failed fuel temp sensor, coolant sensor, whatever. Can I put it in a limp mode, does that help? Try and learn the function and the test— it will help a ton! If you are confused on how to test something, just ask, but try and read up a little first. The above links will help. Personally I hate 13CU/14CU/14CUX systems— I’ve spent way too much time on them, lol.