I put in new plugs distributor cap and rotor.New fuel pump relay. Cleaned the MAF with MAF cleaner. Also cleaned the throttle body with throttle body cleaner. I did a smoke test like Robert DIY's video and couldn't find any leaks
I went to auto zone and got these codes P0141, P0137
I ran the on-board diagnostics here are the results.
A2 I got the following codes 436 Rear HO2S compensation, 522 Rear HO2S Preheating, 153 Rear HO2S signal, 212 Front HO2S signal. I looked them up and got alot of info I coulnt make any sense of. Could someone point me in the right direction.

I really appreciate all the input from you guys, what a resource!

Yet the check engine light is still on, any more suggestion would be great.

Thanx to all of you.

Rick....

 

the way the O2 sensors work is that there are two circuits: one is the heater and the second is the sensor. Code 0141 is saying there's something wrong with the heater circuit (ie open or shorted or the voltage is out of range) Code 0137 is saying the signal is out of range. This could be caused by the heater element not functioning. Since the Volvo has two O2 sensors, you can get codes in the OBD1 for either the front or the rear sensor (aka upstream and downstream). Now the thought here is, if the upstream sensor is not working, the downstream may go out of range trying to compensate.

The real question is, what can cause both O2 sensors to fail at the same time? If you ran your car with a check engine light on for a while and it was running overly rich, you could have gummed up both sensors as well as the cat converter with carbon. You can try pulling the sensor to see if its a bronze/gray color or if its oily black or you can do some electrical diagnostics - there's some stuff on youtube but my sense is they got contaminated by the mixture being off.

There are other possible causes to check out - an exhaust leak near the manifold/downpipe can throw off the sensors, if your model has the secondary air pump and that's faulty it can also throw sensor codes... Just some other things to think about - assuming you are correct that there is not a vacuum leak.

 

I found this open valve on the drivers side up under the front bumper.Wach the video and tell me what this is and should it be capped. I did a little research but was unable to find anything quickly so I figured I would go to my best info tool VOLVOFORUMS.