Noisy engine (5.7)

[Stlrboo]

Back again.. This 99 Tahoe, which I bought new, seems to need to have an issue, or it isn't happy..
Finally decided there is no 'real' fix for the moisture in the distributor cap, so I just replace it when necessary, and stay away from the Duralast cap/rotor..

Tahoe wouldn't start the other day, so I replaced the above.. Starts now, but is very noisy when running.. Last time this happened the 'Mechanic' changed the oil and put in a can of STP.. little noisy at startup, but would go away after a minute or so.. Noise is back..!! Sounds like clacking lifters/rocker arms.. Oil pressure is erratic at times when revving engine above 1000 rpm, but more to the 'high' side, not lack of.. Oh, did I mention I got a backfire thru the TB on startup.. only the one time so far!

Anyone have any ideas..? Tahoe has been babied.. has 84,000.. :help:
Luckily, I have an 88 Fiero GT I can drive when the Tahoe is having these tantrums.. :waytogo:

 

[lesterl]

What do you have in the Fierro 2.5/2.8? (or 3.4l?)

Could have spun a bearing causing the high pressure.

What brand of cap/ rotor are you using? Is the screen in the base of the distributor clean/clear?

Have you pulled the VC's and checked how tight the rockers are?

 

[Stlrboo]

Fiero is a stock 2.8.. This is a GT with the wing.. black with T-tops, 5-speed, gray leather, upgrade radio with equalizer and subwoofer..

Can't find a screen in this distributor..
Had an Accel cap/rotor the last time and it lasted 9 months..
Previously used Duralast, but noticed a larger than normal gap between the rotor and cap electrodes.. they would last 6 months at most . just put in AC Delco

Thinking its time to put it on the Analyzer and see what it comes up with..

VC's are next..
Thanks for the help.. Any other ideas..?

 

[lesterl]

Like rattly? Have you seafoamed the intake, perhaps the cylinders are carboned up?