Code 45

'87 Chevy G20 Van...1000RPM when cold, 15-1700RPM when warmed up, starts great, good vacuum, great power...
Got a code 45 which is a rich condition(at the O2 sensor). What specific
areas does everyone think(or know) I should look at before changing the O2 sensor(if needed).
...Injectors, MAP sensor, IAC solenoid, TPS, FPR, fuel filter, Fuel pump, cap and rotor...all good. New EGR valve, EGR solenoid, and timing set. Plugs look great and wires all have good Ohms. I should probably change the plugs and wires before the snow falls though huh?
What's everyone's ideas, opinions, and experiences about this?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Shades wrote:

    The high idle when warm should be your clue. Fuel Injected vehicles idle Higher when they have a vaccume leak, where as carburated vehicles idle lower.
    Warm in gear I beleave the idle for that van (check the emmissions decal for better info) should be about 750 to 850 RPM's. The van probably has a thermial vaccume switch on the thermostat housing. Test by plugging vaccume lines together and let vehicle get up to operating temp. if Idle drops to a more normial range, the thermial switch is bad. If no change, try running a new vaccume hose from the destination of the switched vaccume. Charles
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Good point...I will check it! Thanx!

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Engine temp sensor not sending the proper warmed up temp to the ecu can cause a rich mixture and not set a temp sensor code, a scanner will reveal this. "Shades" <shades_1970(at)netins(dot)net> wrote in message

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
ALSO a good point...I will check that too!

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Coolant temperature sensor, if it has one. I think it's another one of the gadgets that helps the computer to set the idle mixture. If it tells the computer it's zero degrees when it's not, then the mixture is going to be richer than needed.
I hope I got that right, I'm sure somebody will help me out on it if I didn't.
RJ in WV
"Shades" <shades_1970(at)netins(dot)net> wrote in message

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.