My 78 308's oil pressure gauge has been acting up for a while now, but very recently has gotten worse. The oil pressure sender was replaced in 42k miles by PO and then again by me at 54k miles; I saw no change in behavior when I replaced it. When driving, the gauge would alternate between reading normal (95psi or straight down) and somewhat below normal (halfway inbetween nothing and normal). The other night (one of the coldest in a while), it started flailing wildly for the first five miles or so of my trip home. It would rapidly fluctuate between hard "0" and normal, maybe around two or three complete round trips per second. Yikes! Either my oil pressure is actually freaking out (not likely), the sender is having issues (was just replaced), the electrical system is causing shorts/etc that are screwing with the signal to the gauge, or the gauge itself is on the fritz. Anybody every seen anything like this before? I hate to think what a new gauge costs...! --Mike
Ferrari UK sells these. Oil Gauge, p/n #60198206, supercedes 108790. I would hope they look identical to original. Price is 85.10 pounds, or $144.87 US. Anything else this could be other than the gauge?
Before you start to panic - when was the last time you replaced the oil and filter, what filter are you using (some filters can make a difference to the indicated oil pressure). If you are sure that the oil and filter are okay, I would check the following :- 1. Oil level okay 2. Check the oil pressure with a master guage 3. Oil pressure relief valve may have an obstruction MW
I would still say it is the sender. It has one wire so I assume it grounds through the connection at the filter housing. International auto sells them cheap. You can check the gauge to make sure it isn't a faulty ground up stream. Remove the wire and touch it to a ground. The gauge should read max.