For the past few times that ive been driving my 93 auto firehawk, ive noticed when im just cruising and if i let off the gas, the oil gage starts going up and down randomly and pretty quick. same thing if i stop at a light or something. when i hit the gas again, the pressure returns back to normal. any ideas what this is? I have a 96 T/A with a 6 speed and it has never done this.

 

One thing to notice is if it does it under braking. If you apply the brakes really hard? Does the pressure fall down. If so that would be a fallen off pick-up tube in the motor and something that needs to be fixed. See if that is the case. If not , maybe a bad sending unit or a short in the wire somewhere. Are you full on oil? Sounds dumb but check the obvious first

 

My Fuel Gauge started doing that until it decided to peg itself all the way past full and stay there. The gauge could just be going bad.

 

what I would do ASAP is do get a cheap machanical oil pressure guage and hook it up where the stock electric oil pressure guage sender is. Then I'd drive it to see if it's really the oil pressure thats screwy or your electric guage and sender has messed up. You need to do this to find out though if there is really a oil pressure problem, if so get it fixed ASAP.

Brian

 

Just a thought, if your gauge started this recently and you got gas at a Shell station in Florida...hope you are aware of the news about the high sulfur gas that is taking out peoples gas sending units in the tank.

 

shoebox,
I actually never buy gas at shell. Are there any other stations that use the same gas?

 

I would suppose that it could be sold under other independent station names. I would be trying to find out if you think you might have been a victim.

 

shoebox,
It happened immediately after i ran out of gas. When i finally added some gas and started my car, the gauge was going crazy, and eventually pegged itself past Full. It could have had something to do with the gas can I used, but it was pretty clean.

Where exactly is the sending unit, and how hard is it to replace?

 

The sending unit is part of the pump assy that is inside the gas tank. I believe that Shell is going to have to pay for a bunch of replacements. The high sulfur corrodes/ruins the contacts on the unit.

 

I think I'll start buying my gas at Shell so I can get mine replaced for free