I have a 1988 t2 with an fd oil regulator. lately i have noticed that when i get into boost that my aftermarket gauge will jump around. Once i take my foot off the gas the needle will fall to less then 10 psi. But if i stay out of boost it will be act normal and stay around 15 at idle and rise like normal. anyone have any idea what may be causing it to act this way.

 

Where did you locate the sending unit for the aftermarket gauge?

 

At the oil filter. Btw i don't know if it makes any difference but my turbo is a s5 bnr stage 2 with the 360 thrust bearing and I'm running an .065 restrictor.

 

now i have been reading up some but does would it worth while to try and shim the pellet and if that fixes anything.

 

That might affect you idle pressure but probably won't address the "bouncing under boost" issue.

 

Well i might try it and see if it doe anything. Part of me thinks that it could be the front cover o ring is not seated right could that maybe cause it? Also would it helpful to try and clean the sending unit for the gauge and see if that changes anything?

 

i think i have fixed the problem. i was running 10w30 oil but switched to 20w50 and no more jumping around.

 

i run 20w50 in my n/a and it make a lot of difference. I also run solid mounts and i can tell a huge difference in vibrations between 10w30 and 20w50 the 20w50 make the car much smoother

 

20w50 ftw.

 

None of this makes any sense.

 

well i know it sounds strange but its true i switched and i didn't have the problem anymore so i don't know.

 

i mean as far as vibrations because of the extra cushioning from the thicker oil

 

would a bad oil control seals cause a drop in oil pressure ?

 

If it were bad you would be getting blue smoke out the exhaust....

 

It's probably a loose connection somewhere.

 

i am getting smoke when i start up and when it warms up it goes away.

 

thicker isn't better. the higher the viscosity, the higher the pressure but the lower the flow rate.

 

Changing weights of oil should drop your pressure, not fix it from bouncing around. I'm going to agree with tex and say you have a loose connection somewhere.

Are you running your aftermarket gauge off the stock sending unit? If so, its not doing any better than the stock one and maybe the sending unit is bad.

 

no I'm running a defi gauge off an oil filter adapter and I'm running 20w50 and it still seemed two low after it warmed up. this way sound like a weird question but if the oil filler neck wasnt pressed into the block would that allow pressure to get out ?

 

Oil filler neck is not pressurized, no.

 

happened to me lately.

change your oil filter and your oil.

 

I think over the winter I'm going to tear into it and replace most of the oil stuff and see if that makes it any better.