95 rodeo...ticking sound and low oil pressure

[plurge]

This has been a problem that has been going on for a while (6 months off and on). Usually about 2000 miles after an oil change I would notice a ticking sound from the engine. It would then go away after the change. But recently I've noticed the ticking sound, which is still audible but not as loud and low oil pressure (as per the gauge). On top of that, if I do any interstate driving over 20 miles the check engine light comes on and stays on till the car is cut off.
I've read in a few of the threads already posted that a more frequent oil change and perhaps an oil additive might help the problem. Could this also be a sign of perhaps a bad oil pump?
The Rodeo in question has 178,000 miles on it. Any help would be great.

many thanks,

[2eyefishclaw]

try seafoam most autoparts stores have it and try changing your oil every 3,000 miles and add the seafoam for the next three oil changes

[plurge]

Thanks for the advice. I bought Rislone instead and added it with Mobil 1 synthetic during an oil change last week. 5 days since then, I have had no problems with the car. The ticking sound has pretty much gone away and my oil pressure seems to be pretty working as planned. The acid test will be driving it on a semi long distance and seeing if the "check engine" light comes back on.

I am assuming I should use this additive with each oil change or would this one application be fine till I have problems again?