oil pressure gauge

[motomike33y]

Trying to put an oil pressure gauge on my 91 jetta 1.6 NA.  Got sending unit and adaptor and put in head--but doesn't appear to have any pressure when vehicle is running.  Put it where low pressure sending unit used to be.  Should I try above the oil filter?  Not VW gauge or sending unit, but I tried a couple different unit/gauge combos-never had problem with oil light staying on w/low pressure sending unit.  suggestions or guesses?  thanks

[warp.routine]

Was the location ont he back of the head in the center? That is where mine is. I didn't install it, so I do not know if the connection was pre-existing or drilled for purpose.

I see no real issue with reading your oil pressure from the oil filter mount, however that would only indicate a systemic pressure drop in the event of a failure... if you start having low pressure only in the head you will not see it on the gauge.

[ashleyroe]

Trying to put an oil pressure gauge on my 91 jetta 1.6 NA.  Got sending unit and adaptor and put in head--but doesn't appear to have any pressure when vehicle is running.  Put it where low pressure sending unit used to be.  Should I try above the oil filter?  Not VW gauge or sending unit, but I tried a couple different unit/gauge combos-never had problem with oil light staying on w/low pressure sending unit.  suggestions or guesses?  thanks

i took the sending unit from a cabriolet, put it on the side of the head, ran the wire, ground and illumination for the gauge.

you need the correct sending unit for the gauge your using.

i have 3 bar at idle and 5 when driving.

[motomike33y]

 I don't have vw sending unit, but bought a couple different gauge and sending unit sets w/american thread.  Installed w/metric adaptor on end of head where other sending unit  was.  Even driving down the road, I show minimal, if any, pressure.  One gauge pegs to far end when I turn on key, then slowly drops from about 20 psi to near zero.  Revving engine has no effect.  Engine has 212000 miles, but oil pressure can't really be that low can it?

[ashleyroe]

i think something with the sender isnt right. cause even my cabriolet with 240,000 on it showed 3 bar when driving and 1 bar at idle. and taht car is hurtin'.

[burn_your_money]

Based on your signature it looks like you have a few different vehicles at your disposal. Try testing it in a different car and seeing if the results are the same.

[fatmobile]

If you disconnect the sender while engine is running;
 the gauge should peg.

[motomike33y]

The gauge does peg without the sender connected.  To add more puzzlement, the high pressure buzzer will come on when I test drive the car or rev the engine.  Senders were inexpensive(read 'cheap' but new off ebay) and both act the same.  will keep experimenting.  want to get car back on road someday soon.

[Greenthings]

 Bentley manual says 1 wrap maximum of plumber's tape and suggest (None). Causes bad ground. Gives syptoms of erradic Too High and Too Low ( VDO Oil Pressure Gauge). Might be taped. Been there. Did it (2 wraps). Had to fix it.

[wolf_walker]

I have a lot more faith in mechanical gauges myself, just mind the hose routing.

[motomike33y]

did get the car on the road, put a tank of fuel thru it, getting 40mpg.  went on the x-way, getting above 60 mph when knock-knock-knock, rod broke under piston and went thru side on each side.  now going to swap tranny and put 82 rabbit engine in car.  maybe lack of oil pressure was significant?  no sign until hit the freeway tho.