Cadillac STS Forum - 2005 through 2012 Discussion, EGR Valve for 4.9 or 4.6 in Past Cadillac Vehicle Discussion; I have a 1993 STS and am replacing the EGR valve, but quite a difference in price pending on which ...
- 12-23-04 02:58 PM #1Cadillac Owners Member
- Join Date
- Aug 2003
EGR Valve for 4.9 or 4.6
I have a 1993 STS and am replacing the EGR valve, but quite a difference in price pending on which motor you have. How do you know if you have a 4.6 or a 4.9. I was told that a 4.9 was the Northstar, but was told that the part # from the EGR Valve says I have a 4.6. Can someone help???
- 12-23-04 10:46 PM #2
Re: EGR Valve for 4.9 or 4.6Originally Posted by junkalac
If you have a 1993 STS you have a Northstar engine. The Northstar is a 4.6 liter engine. The "4.9" is a completely different engine that is not related to the Northstar. If you look at the silver top cover of the engine intake manifold I think it says "Northstar" on it.
Chances are you do not need an EGR valve.... If the car is setting the EGR pintle position code (Code P036) all that is required generally is cleaning the EGR valve. Specifically, remove the valve, look up inside the cast passage in the base of the valve and clean the shaft that the pintle valve rides on. The carbon and deposits on the shaft inside the passage cause it to stick and cleaning it generally resolves the problem. Be careful when using solvents to clean the shaft so as to not let solvent run down the shaft into the can of the vavle as the solvent will eat the insulation off the wire windings inside the can. Hold the valve right side up when using solvent on the shaft.