Pcar944

This is why I love Rennlist.

Its bothered me and I've worried its a symptom of some bigger issue but from now on I wont worry about my jiggly gauge.

tjbreen

One thing I noticed is that my needle bounces to a rythym similar to a bouncing ball about once per second. First there is the biggest bounce followed by the longest dwell, then at least two more smaller faster bounces before the next big bounce. Since the period was not regular while at a constant engine rpme, I figured it was not related to anything mechanical.

86_951_

So, is it safe to say that this is a mere annoyance and not indicative of anything really wrong. Do most 944s do this? It seems like a lot more than just a few isolated cases.

Wipeout

I'd make sure your grounds are clean and you're properly filled for oil, but yeah, I'd say this is the rule rather than the exception.

JustinL

Mine started doing this very recently and I solved it by just changing the oil filter. I always use Porsche filters and just put a new one on. Now my oil pressure is back to it's usual steadiness.

Voith

older gauges tend to do that. replace it with the newer and it'll stop. atleast mine did.

JayVee

I think bouncing oil pressure gauges and whining trannies were standard on 944s because there's no option code listed in my trunk for either of these features.

86_951_

DarkGrey

LOL! I hope that line isnt trademarked material because I'll be using it with my car more than once I'm sure!

FRporscheman

Just because everyone's gauge bounces doesn't mean it should be like this... we should all try to figure out how to fix it rather than accept this as the norm and continue to let them operate like this.

I know this can be fixed. Some people have tried different things and many times it's a different thing that fixes it? So are there multiple malfunctions that can manifest as this same problem?

86_951_

You can try to fix it all, but as for me and my car, I'm willing to live with it. As long as it's getting oil and I'm not actually hurting anything, I can live with the gauge bouncing. Sometimes it's in sync to the radio, or the blinkers. That's always a real treat.

Kburke

it should he faulty ground if it was the sender unit it would read high all the time that's what mine does clarks-garage.com has some good info on this

Wipeout

I think it's largely electrical - mine does something like this:

At idle, sitting at stop light shows 2.
Look back at gauge (still at stop light), now shows 1.
It snaps back and forth if you watch it long enough. Where's that really good photo of all the grounds again?

931guru

There is a theory that a bouncing oil pressure gauge is a sign of a rod bearing starting to go south. As the bearing for the oil hole in the journal is uncovered (especially at idle), the pressure drops a bit.

Of course, that's only a theory, so drive in peace.

StoogeMoe

The gauge bounces because it isn't damped. What you're seeing is the resonance of the OPRV as it covers and uncovers the orifice in the bore.