99 STS MAJOR Issues

[Maiahsdad]

After at WOT last Sunday night, i noticed a VERY noticeable ticking or knocking or clacking sound at startup on Monday morning. After 2-5 minutes it's not noticeable anymore. And, the "check coolant" message comes on (I'm told I have a leaking water pump). It's also now (following the WOT) running VERY noticeably HOT at stop lights and very slow traffic. On the gauge where it's normally at the NOON position, it slowly will creep to possibly 2 O'clock position. But goes back to noon after I start moving again.

Mechanic says it sounds like lifter not pumping up at start up, and that I should add two bottles of CD2, drive the remaining 1500 miles to my next scheduled oil change and put another two bottles in.

I'm SO afraid that I've blown a HG or destroyed something in the engine.

I live in Indianapolis, and it's cold in the mornings ad here lately warm in the afternoons. It makes NO difference what temp outside. Even after sitting for 4 hours, the ticking or pinging or whatever that disturbing sound is... returns for the first 2-5 minutes.

Can anyone help?

[Texas Jim]

The ticking/knocking may be what is known as "COLD CARBON RAP"

Not uncommon on the NorthStar.

There is actually a "WOT PROCEDURE" to help take care of the "COLD CARBON RAP" problem.

Do a search for it.

I assume you don't check your coolant level very often... because you got the low coolant message.

If you know it has a leaking water pump, you should check it frequently and keep it at the proper level.

If you just now found out about the leaking water pump, and didn't know about it till the "CHECK COOLANT" message came on... I apologize for the above statement.

There is a coolant test kit that you can get from NAPA (and other parts stores) to check the coolant for combustion gases to see if you have a blown headgasket.

At this point, I wouldn't jump to conclusions just yet.

One thing to check is the little line that runs to the side of the coolant expansion tank.

Take it loose with the engine idling...there should be a steady flow of coolant from the line.

If there is "NOT" a steady flow... follow the line to the other end...and take it off and clear the obstruction.

[Bruce Nunnally]

Wow, nice response Jim. I can only think of one thing to add:

Maiahsdad