does a car tune-up include checkin the whole electrical system?

Question

Hi everyone, not sure if any of you saw my other post, but anyway my car is a mercedes 350SDL 1991 (about 150k miles).
I have two main issues that I just discovered recently.
1) my fuel gauge reads incorrectly- goes to Empty even though it shouldve been around 1/2 tank. It sometimes jumps back to the actual value, but will eventually go back to Empty. Sometimtes it will even move sporatically for a second or so .
2) this happened twice ot me the other day - once when parking and the other when pulling out in the middle of a Kturn - my car completely shut down. It looked like all my dashboards icons flashed for a split second and then the car went off. I turned it back on right after (both times) and drove it fine.

Could these problems be related? Does a tune-up check possible electrical issues such a these? Should i have it done at a chain tune-up place or at my mechanic. (both these issues started happening the same day- althought have not drivenmuch)

thanks for the help!

im asking this because I have a hunch the cars parts are working fine- because the mechanic is very good with foreign cars and it had been running fine before. However I know a lot of the cars functions run through the car computer - so even if the part is ok it might not function properly because of an incorrect computer reading right?

To jsygrove.. how much are we talking?

ok i filled the tank to full and now the gauge works fine and doesnt go to empty or anything -- havent noticed the shutting down problem (issue #1) but then again that doesnt necessarily mean anything. That only happened twice ever- and im not sure what triggers it other than being idle - but ive been idle plenty of times in traffic and it has not happened

Answer 1

A tune up won't check the issues you have. You have to have the problems diagnoses separately. Yours sounds like a computer problem.

Answer 2

A tune up does not cover searching for an electrical problem. An electrical problem that you are describing could take a few hours to diagnose exactly what is causing the problem.

However I can tell almost predict that the problem that you are having is either the computer or some type of grounding issue. It is very possible that your symptoms are related. The grounding issue may be with the signal that sends the information about how much fuel is in your gas tank actually causing some type of interference with your fuel pump. (I'm purely speculating here since I'm not looking at the car). When the car shut down both times, what the fuel below your 1/2 tank mark?

Electrical problems are difficult to trace and take time with a volt meter to determine the problem. Mechanical problems with a car are much easier to find as they are typically visual. A problem with an intermittent grounding is even more difficult to find.

Keep your gas tank between 3/4 and full and see if you have you stalling/shut down problem, if not, then your problems with the gauge and shut down are more likely to be related.

Answer 3

A tune up will not cover the electrical system unless the technition notices the problem or if they plug the car into their computer (which im not sure they had on cars from 1991). If you want to find out the problem bring it to a mechanic to have them diagnose it. It sounds like a short in the electrical system. Its going to cost some money but it should fix the problem...

Answer 4

On modern cars the computer takes care of a lot of functions that used to be replaced in a tune-up. Now most tune-ups just replace the spark plugs, check the plug wires and maybe change the air filter.

But you car is a diesel. Diesel engines don't use spark plugs they have glow plugs which are not replaced in a tune-up. Most likely all the did was replace your air filter and clean your fuel filter or at least drain the water out of it.

As for your fuel gauge, that's not part of a tune-up. Most likely it is a bad sender, which is most likely located in the tank and will require the removal of the tank to fix it.

Good luck

Answer 5

No.