I connected the mechanical gauge in place of the factory sending unit immediately after detecting the drop in pressure with the factory gauge. With the cheapo mechanical gauge, I never dropped below 20lb. I then reconnected the factory gauge/sending unit and again got the flutter and drop in pressure. So, it was pretty clear I had problems other than oil pressure. I replaced the sending unit with no change. I then got another gauge cluster from a salvage yard and it did the same thing. I had another strap identical to the factory stap that connects the block to the firewall, so I connected it as just a guess. I think the problem was the connection at the firewall - screw could have been tighter.I'd check those connections and if tight try adding another strap. I'd think any larger gauge wire would work. The factory gauge now never reads below 30lb at idle in gear.
I've also had the connections at the battery cause strange problems - as well as the battery itself. So, I'd start at the battery and load test it, check connections, check alternator output, belt etc.
Friday, October 6th, 2006 AT 8:53 AM