1998 S70 GLT approx 136k miles
I've spent a few hours with Google, this site, matthewsvolvo site, and others and am finding myself w/ a bit of info overload. Have learned a lot though. I apologize in advance as this is long and would appreciate some help.


I'm getting codes P0172 and P0455 and a pending P0410. I've got an emissions test due by April 30 and have been trying to diagnose the codes. I disconnected the battery and have spent the last couple of days attemting to complete the drive cycles to complete the readiness monitors. I've put about 170 miles and have yet to clear the catalyst, evap system, secondary air system, and oxygen sensor monitors. Cleared oxygen sensor heater yesterday. I'm assuming that evap and secondary air will not clear as they gave codes.


I got codes last go around in 2010 with P0442, p0455, and P0108. My indy performed a smoke test and replaced the purge valve and an evap hose by the rear canister. I replaced the gas cap with OEM before taking it in for service. I'm guessing the the P0108 cleared with the resolution of the other codes. In 2008, the O2 sensors were replaced.


My questions:
Re: the air sensor code. My air pump runs on cold start for a little over a minute. I can hear it turn on and can feel pressure in the hose running to the air box. I've got a vacuum guage and plan to test the SAS valve this weekend. It's a bit tight around that valve so I'll have to purchase some different wrenches. I found a set of flex stubby ratcheting wrenches at Harbor Freight but they are out of stock. Any recommendations? How do you remove the clamp without destroying it? Since this code has not gone permanent, do you think it will eventually clear?


My permanent codes (172 and 455). Which one do I attack first? I believe I read from some service instructions I found on line to investigate the gross leak issue first. I've pretty much dug and poked to check my vacuum lines as much as I could. My resources are limited. I drive up onto the curb on the passenger side and crawl underneath. With everything packed under the hood as it it, I've fingered my way through much of the lines' paths. I will attempt this exercise again this weekend. perhaps I should check with friends to see if any of them have ramps.
Anything I'm missing?


I've got a multimeter to check these components, but I need instructions
or links to assist me.
My Scan tool is an Actron CP9575 and provides live data.

How do I monitor fuel trim. I've got readings for STFTRM1, LTFTRM1, and STFTRM11. What is STFTRM11? How does it differ. Most of what I recorded(wrote down while idling) When traveling at speed, the numbers are at a fairly low percentage and relatively close to each other. However after coming off the highway and at idle before shutting down, my STFTRM1 will approach 20% and beyond.


O2S11 and O2S12 are relatively close and range between 0.03% and .8%. What are the limits? I'm assuming O2S12 is the rear sensor. Is it supposed to be continually lower than the front?


My uncompleted monitors. How do I clear the converter, secondar air, and O2 sensor monitors? I've got a couple more days to run through the required cycles. Any specific methods to complete?

MAF - What do I look for here? I'm generally in the 0.2 to 0.3 lbs/minute.
I guess this is a start. Thanks for any assistance.
Roger

 

The P0172 is likely a loose vacuum line. When I had the code, I have a loose vac at the PTC valve, the small line. When was the last time the entire PCV system was replaced?

 

@rspi, what is PTC valve??
I have the same code(s) -> (p1072 and p1071) on my 98 s70. I replaced elbows under the intake, coolant temperature sensor (because fan was staying on all the time), cleaned maf with crc cleaner. Code p0172 is always on, p0171 comes and goes. My state inspection is coming soon, I dont know what to do next?!?

 

Here is a pic of the PTC valve. The elbow has a line going to it and line #10.



That line goes around to the front side of the manifold so you may want to check that side as well.

http://www.matthewsvolvosite.com/for...hp?f=1&t=28415

 

Thanks! I couldnt find it. My car is non-turbo, if yours is turbo-maybe thats the difference. Anyway, today i got the code for IAC valve. I cleaned it, its moving freely but code is still there. Another part on my list

So p1071, p1072, p0440 and now p1505. Car runs fine even though mixture is obviously not good.

 

Did you clear the codes? ALL S70 GLT's are turbo.

 

I know, I used to have glt and crashed it. This one is just plain, non turbo.

I think I will take it to mechanic that can do smoke test, i have tried everything else already. I installed new IAC valve and i still get p0505 code.

Also, today after i filled it up at the gas station and started it it just died. Started it again and kept my foot on gas pedal for few seconds and it was fine after. This is the second time this happened after a fill up. What could that be?

 

IDK. I'd search the codes and check wire connections. Maybe you have a bad ground somwhere.

 

Cleaned and replaced some of the wire grounds. Still getting p0172 and p0505.
Car runs great and if it wasnt for state inspection i wouldnt touch anything but...

 

me again

Smoked it, found minor leak on the boot going onto TB. Replaced the boot, smoked it again, no leaks.
I also installed new Idle air controle valve and new MAF. Still getting p0505, p0172, p0440 and today i had p0413 shortly but it went away.

What are the chances of my ecu being bad? Because it would throw some strange codes once and never again. Driving me crazy.

 

I really don't know. Drive it for a week, reset the codes, and see what happens.

How old is the PCV?

 

Ground wire was the problem, rspi you were right.
I did spend some money on new parts but i plan on keeping the car for at least 2 more years so it will pay off.
Cleared all the codes, drove for 60 miles no codes coming back. They used to come right back so I am pretty sure its fixed. The only problem I have right now is that I am not getting readiness on anything, all those lights on my obd2 scanner are flashing. I thought I should have at least something after 60+ miles?! Going to put another 50 miles on the car today, hopefully it helps..

Thanks for your help!