Oil Gauge or Oil Sender Bad....Plus Added Attractions!

[jh225]

Ever since I changed my oil and put Brad Penn 20w50 in a few weeks ago my oil level gauge has been showing low while it used to go to full after a minute. No big deal as they are not accurate and I check the dipstick anyway. Druck pressure is alway 4+ bars at speed, 2 1/2-3 at idle. Temperature never goes more than barely past first line. Life is good.

Soooooooooo, today we go out, everything as normal then I notice my Druck pressure is past the 5 bar mark! As I slowed for a light, the pressure didn't drop back down. So I watched it for a while, all else was perfectly normal. A little later it dropped some, did some fluttering moves around 2-3 bars and then when I went to maybe 4K rpm, it went slightly past the 4 bar mark and then kind of stuttered and shot past the 5 mark.

I was still trying to watch it when we get a call that my house is on fire It took around 25 minutes to get from where I was to the house (siding caught fire, no wood damage, but VERY close to it all going up in smoke. Neighbor actually put it out before FD got there). So in this 25 minute "drive" at double the speed limit, the car performed flawlessly. I of course didn't notice the gauge though as I was a little pre-occupied.

So I am trying to decide if it is the sending unit which may be acting up with the thicker oil????????? Or the gauge starting to crap out. I don't want to just spend money on the sender if it is not the issue.

Anyone have this problem? (besides the house fire of course )

[ShakinJoe]

I amcurious to see answers as I am about to switch to BP oil.

[GothingNC]

I had the same thing happen after an oil change.

It would peg at 5 bar and was really high at idle.

Gauge went back to normal after about 15 miles.

[jh225]

Originally Posted by GothingNC

I had the same thing happen after an oil change.

It would peg at 5 bar and was really high at idle.

Gauge went back to normal after about 15 miles.

The high reading didn't happen right after an oil change, its been a few weeks and probably 500 miles.

Anyone else?

[fintstone]

Is the thermostat in the wheelwell for the external cooler opening? Are the lines geting hot?

[jh225]

Originally Posted by fintstone

Is the thermostat in the wheelwell for the external cooler opening? Are the lines geting hot?

Yes, the lines were hot last week when I checked. Although non working thermostat/cooler would affect temperature, not pressure.

As I said, car runs perfect, just trying to find out if it is the gauge or sending unit.

[fintstone]

Originally Posted by jh225

Yes, the lines were hot last week when I checked. Although non working thermostat/cooler would affect temperature, not pressure.

As I said, car runs perfect, just trying to find out if it is the gauge or sending unit.

You said you had an oil level problem as well. Do you think it a coincidence? Oil level and oil pressure problems will not stop it from runing perfect...until stops running completely.

[Pazuzu]

Oil change broke some gunk loose, which is now interfering with the sender(s). Pull each, wipe 'em down, reinstall. It's possible the sender is going bad, but I'd bet that you just have some loose gunk from the force of changing the oil.

[jh225]

Originally Posted by fintstone

You said you had an oil level problem as well. Do you think it a coincidence? Oil level and oil pressure problems will not stop it from runing perfect...until stops running completely.

No, not an oil level problem as in low oil volume. Just the gauge is showing low. As we all know, that particular gauge is not accurate and the dipstick must be used. I check my oil level via dipstick all the time. It is 3/4 to the top full line, and has not moved in at least 500 miles.

[jh225]

Originally Posted by Pazuzu

Oil change broke some gunk loose, which is now interfering with the sender(s). Pull each, wipe 'em down, reinstall. It's possible the sender is going bad, but I'd bet that you just have some loose gunk from the force of changing the oil.

That's what I thought, but it is weird that it did a little flutter around 2-3 bars and then once it goes a tiny bit past the 4 bar mark, it shoots to way past 5 bars mark. That to me leans more towards the gauge.

I know where the oil pressure sender is, but where is the one for the oil level?

[jh225]

Originally Posted by Scott S.

Thankfully, and MOST importantly, you have a quick thinking neighbor and your biggest problems today are oil pressure and matching the new siding to the old!

You got that right. When my wife as I was driving got the call, the first thing I was worried about and tried to get a straight answer to was "is the house burning"? My 2 very large dogs are inside.

I had actually left my mint condition, very low miles E430 M-B in the driveway when I pulled it and the 911 out of the garage. Something I never do. My neighbor who said their plans to go out were changed that morning happened to be outside on his deck, smelled smoke, then realized what was happening. He happened to have a dry chem extinguisher, the fire chief happened to be around a mile away, I happened to have a pool and a couple of 5 gallon buckets were outside. If all that didn't happen, by the time the trucks got there it would have been fully engulfed.

A lot of things fell into place like a dream.

My other neighbor was crying and yelling at the fire guys to get the dogs out, but thankfully, it never became an issue.

I am just glad I am not typing this from a hotel room. Another 30 seconds to 1 minute and it would have all gone up in flames as the siding burnt up to the soffett. and once the rafters caught, poof.

[Wil Ferch]

When all this sorts out let's not forget something.....the guages are indeed VERY accurate and portray the comings-and-goings of the oil system VERY well. People just don't understand all the things that are going on.

let's start here....the oil level is checked when ALL THREE of these things are in-play.
- level ground.
- oil at idle type RPM, say 880-950 or so. As an example.....1100 would be much too high and the level will likely read "low" ( red zone)....AND.....
- oil at temp, this is the usually the 194 degF or second-from-bottom white mark at around 8:00 o'clock position.

As soon as RPM's rise, level ( in tank) will fall, as when usually running and driving the car. Level will start to read "correctly" again at the next stop light.

Most people usually overfill the oil. Make sure that when these 3 things are verified for idle-oil level check, correlate the dipstick mid mark with the oil level gauge reading about mid-level or a bit lower. Very accurate.

PS- perhaps more for oil pressure than oil level, but check grounds too. A broken ground usually makes the gauges read high, at least it does for the oil pressure gauge.

[fintstone]

Originally Posted by jh225

...I know where the oil pressure sender is, but where is the one for the oil level?

It is mounted to the outside of the oil tank. You will see a round plate with a bunch of nuts holding it on and couple of wires coming off it. One to ground and the other to your gauge up front. On the other side, inside the tank is a variable resistor. The resistor connects to an arm with a float at the end that rises and falls with the oil level...changing the resistance and the gauge reading. A bad electrical connection at the sender will cause the gauge to flutter a bit.

[jh225]

Well, before I ordered a new sender, the pressure relief spring, and other associated parts, I figured would take the car back out for a run and see what happens as I have not driven it since last weeks house fire fiasco.

Oil pressure gauge is once again working as it should be. I figure that some little particle of crap was partially blocking the sender opening and after shutting it down for a week, it floated back down to wherever.

Not only did I save $100, but I don't have to go through the hassle of removing the sender block, oil line, A/C, etc.

At least one thing went right. Homeowners insurance however is a freakin' joke.

[oneblueyedog]

Oddly enough I got jinxed after reading this and had a fluxuating druck gauge and then after a few days pegged at 5 bar anything over idle.

I cleaned the terminals on the sender off the cam tower line and the one on the block below. Still pegged.

I then was lamenting the fact that I may have to buy a new sender, etc.

I went to the search archives an found I needed to look closely at the spade terminals too.

I then looked at the spade terminals the next day, in the sunshine. THEY WERE GREEN. Folded some 600 grit to run in and out of the spade slot and crimped it gently to fit tight on the sender .

FIXED.

Hope this helps.

[dshepp806]

I had to replace a section of wire going down to the sender, about a year ago. The wire ran through a retaining clamp up on the shroud. This clamp had moved to one side (skewed), and over time, had worn through the wire's outer casing. Replacing that section of wire (with fresh crimps/connector) made the meter be a bit more accurate.

Best,

Doyle