I've got an 88 Jetta Slalom, fresh oil change, and running fine aside from a few little idiosyncrasies which need diagnosing and tuning up.

After being stuck in very slow traffic (about 30 minutes to move about 10 blocks - during which there seemed to be nothing unusual happening), I finally got onto the highway, and as soon as I got up to third gear the oil pressure light and buzzer came on for a few seconds, then off for a few, then back on, etc for a few minutes (which was all that I was on the highway for), and during the same time the temperature gauge started rising (but the light didn't come on), and as soon as I got off the highway and slowed down back to fourth and third gear, everything went back to normal (oil light/buzzing stopped completely and temperature gauge started falling). I have driven on the highway recently without issues, so it isn't the speed, and I have had problems before being in slow traffic (such as setting off the symptoms of being late for an oil change - oil light coming on and loss of power when accelerating).

I'm pretty sure there are problems with some of the sensors, the temp being one, along with the fuel gauge sending unit. Both my temp gauge and fuel gauge take about 5-10 minutes of driving before they start working, and the temp gauge seems a bit wonky about half the time (such as being way down at the cool end even though I'd been doing a considerable amount of driving).

I'm fairly new to auto maintenance, so if someone could give me a few pointers as to what I might be wanting to look at here, that would be great. I would like to replace the coolant reservoir since it's difficult to tell where the levels are at (the tank is too cloudy) and I am hoping this might fix the temp gauge, and I am also thinking I should do a complete coolant flush at the same time...is there anything else I should be looking at?

Also, I'm assuming that the fuel gauge sending unit issue and the temp gauge issue are unrelated, and figured I would just not bother having the fuel sender replaced, as it works well enough for me as it is...any opinions on this?

Many thanks in advance for any tips or advice.

 

my fiance's car has had the coolant temp sensor replaced before, and it still has issues. that the temp gauge take 5-10 min of driving before showing anything seems normal for any vehicle that is cold.

the oil sounds like a bigger issue to look at. does the car seem to lose oil? i try to check my fiance's car monthly for oil level as it seems to go through a quart a month, but there is no oil leak and she doesn't blow out smoke, even on cold starts. could be the oil pump going bad. my mom's boyfriend's car has a plugged up oil pickup on it, so the whole car is currently stopped and not doing anything. that requires dropping the oil pan to replace that one part. for things like that, i suggest using seafoam.

seafoam directions (for LT1 motors at least, but can also be used for almost any motor)
http://www.lt1engine.com/tech/how-to...arbon-buildup/

 

thanks for the response...totally forgot to come back and check for answers. I might have to try the seafoam thing, as the oil pump/pickup thing sounds like a very likely culprit.