What causes the oil pressure needle to flicker on a 126 V8? what's the fix? sending unit is new; needle still flickers when engine is warm at idle. Thanks for any help.

Could be the engine, BUT I doubt that.

You could test for Resistance readings at the sending unit & see if they are changing.

Could also connect manual guage to check the oil pressure.

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Mine flickers like mad. it shoots up to just under 3 bar at full pressure. I wouldnt worry about it too much even tough its annoying. Now the twitching fuel gauge, I want to fix that.

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1984 300SD Orient Red/ Palomino
1989 560SEC
2016 Mazda 6 6 speed manual
1995 Ford F-150 reg cab 4.9 5speed manual

remove the instrument panel and run an extra ground from one of the main screws on back of the instruments to the main grounds that are visible there[bunch of brown wires under 10mm head bolts].

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David S Poole
European Performance
Dallas, TX
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"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
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as far as the twitching fuel gauge....had the same problem when I bought my 380SE...a couple of treatments with Chevron Techron solved the twitching.

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95 E420 ( 76K) SOLD
85 380SE(125k)
95 SL500(72k)

take out the instrument cluster and clean all contact points. its a standard diagnostic fix for that type of problem, normally on 123, 124, 126, etc.

The oil gauge on my 560SEC stays somewhere between 2 and 3 bar when I'm driving. It seems pretty steadt (not twitchy). Shouldn't it be pegged all the way at 3 except when it's idling?

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" We have nothing to fear but the main stream media itself . . . ."- Adapted from Franklin D Roosevelt for the 21st century

OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
2016 AMG GTS 12,000 miles

I think the oil pressure gauge on my old 85' 380SE flickered a little at idle and that car had a low reading at idle. It had almost 300K, so I guess the engine was worn out. Fuel gauge on that car was steady as could be.

My old 84' 190D had perfectly working gauges. They were steady as a rock. Oil pressure was excellent, but it only had 152K- which is low for a diesel.

My current 88' 300SEL has a very steady oil gauge and has so much better pressure than my worn out 380SE (with much less 154K miles) had (its around 1.8 bar @ fully warmed idle vs .3 on my old 380SE), but my fuel gauge is crazy. It runs out of gas before it gets to "R", and even after 150 miles of driving after I have filled it up, it will still go all the way up to "1/1". Its very erratic.

Most issues and reading problems with the oil pressure can be attributed to a bad oil pressure sender....they all do eventually go bad and read low or jitter. My one on my diesel got so worn out that it would read 0 at a warm idle and 2 bar at 3000rpm. New sender fixed it....now it reads 2.1 bar at warm idle, and pegs at anything over 1300 rpm when warm.

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Hi, my '86 420 does the same thing. It pegs the needle at any speed above idle, but at warm idle the needle hovers just above the center, and makes a rythmic periodic jiggle at a rate of about 2 cycles per second. All other gauges and instruments work fine. I could buy that something might be faulty, if the motion were not so predictible and rhythmic. Mine is not erratic at all.

Mine seems to just stay between 2 and 3 even when I'm driving. I'll check the sender. It sounds like that's the most obvious place to look first.

__________________
" We have nothing to fear but the main stream media itself . . . ."- Adapted from Franklin D Roosevelt for the 21st century

OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
2016 AMG GTS 12,000 miles