Hey guys,
Still on my quest to pass the NOx portion of the emissions test. I am currently double what the limit is. I have heard that the EGR system needs a little exhaust backpressure to fuction properly. I wonder if I have too little backpressre for it to work right. LOOK at my Sig for my mods.

This is what I have done so far:
-NEW EGR Valve
-NEW Plugs
-NEW Wires
-NEW 02 Sensor
-NEW Distributor Cap
-NEW Rotor
-NEW Vacum ines
-NEW Catalityc Converter
-CLEANED EGR passages
-SET timing at all different locations (NO HELP)
-SET fuel pressure at all different levels (NO HELP)
-CHECKED for vacum @ EGR valve (15inches during operation)
-ALWAYS ran premium fuel


What do you guys think? Is there some other avenue that I havent tried? How about the backpressure thing? Does that sound like a good idea?

 

How did you go about cleaning the EGR passages?

What type is the new EGR valve - same as original?

 

I used a bottle brush to clean the passages... But I dont even think they were dirty. While the car was ideling, if you push up on the EGR diaphram, the engine bogs. So I have to assume the passsages are good.

I dont know the manufacturer. I got it from pep boys for like $60-$70

 

Reason I asked is some are called "positive" pressure type, and require some pressure in the exhaust side to close a check valve in order for the vacuum to open the valve. A replacement valve can be of either type.

How did you go about setting the timing?

 

well don't do this but my uncle to get cars to pass in colorado he just adds some (methane... mothonal.. shyt i can't rember brain fart) to his tank and dirve around for a bit so it mixes he hasn't had car not pass that way

 

do you mean methanol by any chance?

 

Haha... Atleast people are using the search feature. This post is over 4 years old!

Do we have a new winner?