I'm getting these codes ONLY when the A/C is used.

No Codes when the A/C is not used.

I've changed the AIC And the TPS Sensor.

Replaced the Spark plugs. Wires good, replaced last year and the distributer replaced also.

She idles great when the A/C is not used, the idle was bad before replacing the AIC and TPS.

And yesterday when I was going to the store the CEL light up and started blinking, that is WITH the A/C on.

Just came back from store today and did not have A/C on, no problem...

Thx

Jim

 

Code sheets:
P0154 - HO2S Insufficient Activity Bank 2 Sensor 1
P0174 - Fuel Trim System Lean Bank 2

I'm not sure why these codes would only come up when using the A/C, but you could have a short somewhere in the wiring between the two systems...

 

Thx Kyle,

I had 2 new o2 sensors installed like a year and a half ago, I know they were not AC delco but I know they weren't bosh either.

could it be the autolite spark plugs I put in about 3 months ago? Prior I had the cheapest AC delco's in then decided to install new autolite's.

AND this morning I cleaned my egr valve just in case, I installed a new one like 18 months ago.

JIm

 

Ok, I figured out the problem myself.

I installed autolite double plat about 3-4 months ago and she ran good until I put a new AIC and throttle positioning sensor on. you do have to agree at around 160K miles it's time.

That is when my she started throwing codes with the AC ON, off she was fine.

So today i went to advance auto and bought AC Delco rapidfire platinum and installed them.

idles nice with the AC on. took it for a ride and still idling nice.

Did notice that the autolites were longer than the ac delco and when i pulled the autolites they had a slight red or orange hue to them, what does that mean?

So this just tells me AC Delco all the way....

jim

 

The hue could just be discoloration due to heat.

Where were the Autolite plugs longer? If external, that wouldn't matter. I used to like Autolite plugs in my older vehicles, but their quality isn't there anymore.

 

the treads were longer, I matched up the first one to the new ones and the autolites were longer internally.

I found that weird.

but the new ones are in and it seems like a-ok.... hopefully.

one question as a preventive maintence measure and at the blazers mileage do you think I should replace the VSS sensor?

I have to replace my rear shocks asap and while im under there I was thinking of replacing the vss.

Jim

 

VSS as in Vehicle Speed Sensor? There would be no reason to replace it as preventative maintenance. Maybe clean it, but you don't have to go nuts.

 

oh, ok I'll clean mine, I just thought that with 160K miles it might be wearing out?

But if it just a cleaning then I'll do that

BTW kyle, if an engine runs too rich will not the spark plug have black soot on them?

Thx
Jim