'91 Roadmaster won't pass WI emission test

Failed once, had it checked out and the EGR valve, EGR solenoid, and oxygen sensor were replaced and the throttle body cleaned out. After that, it came
close but not quite. A guy at the testing station told me he heard that when those new parts are put it, it takes a while for the computer to adjust to them ???? I had the work done last Friday and the test on Saturday morning. He said I should drive it this week then have it tested again next Saturday. Sort of makes sense to me but I am wondering if anyone knows for sure if this is correct.
The car failed back in 2002 but after replacing the convertor I got a waiver. The mechanic that worked on it then told me it had so much oil blow-by that it would never pass. The guy that worked on it this time said that was not true and I tend to believe him since he got it within a few points of passing.
Thanks for any input!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

oxygen
came
adjust
next
for
said
There is a reason you don't listen to people at testing stations that are not repair techs. Most of them could not fix an emissions system if they tried. Hence why they work in testing stations.
Take your car back to the guy that just repaired it, with the print out of why it failed. He may have missed something like a cracked vacuum line, or a blocked passage.
Getting emissions wavers does not correct a problem, that will only get worse with time. In places with emissions testing, cars that will pass have a higher resale value. Charles
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What were the CO, HC and NOx readings?

Was this another motorist making this comment or was it one of the test station droids?

Actually, it doesn't make sense. You're going to use up your third test, #s 4 and after will have to be paid for by you. You'll still have to fill out the back of the VIR from the last failed test, what are you going to put down as the performed repairs? (drove some more doesn't count)
Again, what were the CO, HC and NOx readings?

So now it either has to meet the emissions standards or you get it off the road. Waivers are just postponed problems.

Within a few points doesn't mean much considering how lenient the test cut points are compared to what the car was capable of meeting when new.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 08 Aug 2004 17:35:33 -0500, Rob wrote:

I have a 92 Caprice which is essentially the same car. I have about 340k on the motor and transmission due to the fact that I maintain my cars myself and am very fussy over even the most simple problem.
Chances are you have an enormous amount of blow-by which would be pretty normal for a car of that vintage unless it has low miles on it.
Start the engine and pull the PCV valve out of the rocker cover on the drivers side. Do you see the little pintel sucked into the valve or is it sitting at the end of the valve?
If at the end, the passage, hose, throttle body is clogged. Remove the hose from the throttle body and the idle should increase a lot and if you put your finger on the port you should feel vaccuum. If you don't, spray some carb cleaner in there and keep spraying until it clears. Get a new PCV valve as well.
Next item you might want to try is some GM Top Engine Cleaner.
This is basically and enema for your car and is real nasty stuff, but it DOES work wonders.
Follow the instructions on the can TO THE LETTER and warn your neighbors because it creates clouds of thick, smelly smoke but it does work rather well!
Other than that, post your readings.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.