850r failing emissions miserably (HC and CO) Topic is solved

[hausmeister]

Tips from my side:
Always record your fuel consumption. I know it is some work, but it pays off. Note displayed values can be incorrect, I always note distance and fuel consumed.
If you are using excessive fuel then it is not running right. I was able to catch and diagnose some problems early because I saw the cars used a lot more fuel.

Could be a bad O2 sensor, with much higher fuel consumption might point to this.
Also check if the engine gets up to operating temperature (thermostat working)

[JayPea44]

Tips from my side:
Always record your fuel consumption. I know it is some work, but it pays off. Note displayed values can be incorrect, I always note distance and fuel consumed.
If you are using excessive fuel then it is not running right. I was able to catch and diagnose some problems early because I saw the cars used a lot more fuel.

Could be a bad O2 sensor, with much higher fuel consumption might point to this.
Also check if the engine gets up to operating temperature (thermostat working)

The previous owner did do this and from what I can see in his notes it doesn't seem like anything is off. Although he only drove it 3 times last year.

The temp gauge does get to normal temp and displays normal temp. I'm not getting a code for o2 sensors or anything so reluctant to jump on that right away.

[JayPea44]

Just an update fo completeness and future people searching (and maybe some more info)

Last night I check the last stored fuel trims on my obd scanner.
STFT == 0.0
LTFT == 14.2 (this seems very high)

I also poked around under the hood in the dark and cold at some vacuum lines, but couldn't see much on the lines. BUT I did see the fresh air snorkel was loose and not even connected to the part under the air box, and the air box is loose, and I saw a connector under the snorkel pipe that was hanging loose - didn't get to explore much more on it, not sure what it is, but seems weird that it was just hanging there? That's today's work.

Also review the previous owner's mileage log it was only driven 3 times last year, so yeah, it has been sitting around a lot. So probably would benefit from the tune-up coming its way.

[ZionXIX]

I bet of you put a smoke tester on it, there would just be smoke leaking everywhere.

[JayPea44]

I am starting to think that too... Good job this isn't intended to be my daily driver.

[ZionXIX]

Honestly its not that expensive to buy like 10ft of each vacuum hose size and then replace all the hoses you can find one at a time. You can get some pretty nice high quality silicone hoses on ipd website or even amazon.

[JayPea44]

I think at this point that's a smart move.

[WhatAmIDoing]

Just an update fo completeness and future people searching (and maybe some more info)

Last night I check the last stored fuel trims on my obd scanner.
STFT == 0.0
LTFT == 14.2 (this seems very high)

I also poked around under the hood in the dark and cold at some vacuum lines, but couldn't see much on the lines. BUT I did see the fresh air snorkel was loose and not even connected to the part under the air box, and the air box is loose, and I saw a connector under the snorkel pipe that was hanging loose - didn't get to explore much more on it, not sure what it is, but seems weird that it was just hanging there? That's today's work.

Also review the previous owner's mileage log it was only driven 3 times last year, so yeah, it has been sitting around a lot. So probably would benefit from the tune-up coming its way.

I'm not an expert on fuel trims, but LTFT I believe should be low single digits.

O2 sensors rarely throw a code except for short to ground or open circuit. If the sensor has fallen out of spec, the computer likely won't realize it. I would sort out a tune up and other issues that arise first before replacing MAF and O2 sensors.

The fresh air snorkel isn't really a requirement. My car ran fine without one for years. Same for a loose air box, unless you mean the cover is loose.

If any rubber lines are hard, mushy and goey, or show cracking, it's time to replace them (in this case it's probably all of them).

Now that connector is a prime suspect. Investigate that first.

+1 for ordering silicone lines. I know for sure you need at least 7ft of 5mm ID (not 3/16").

[scot850]

Just so you know, the MAF (depending on part number if it ends 107 on the Bosch number) is now only available from Volvo.

You may need to find a used one. If you have no luck with that I have a few including one that was run in a car for 4 weeks.

Neil.

[JayPea44]

Just an update fo completeness and future people searching (and maybe some more info)

Last night I check the last stored fuel trims on my obd scanner.
STFT == 0.0
LTFT == 14.2 (this seems very high)

I also poked around under the hood in the dark and cold at some vacuum lines, but couldn't see much on the lines. BUT I did see the fresh air snorkel was loose and not even connected to the part under the air box, and the air box is loose, and I saw a connector under the snorkel pipe that was hanging loose - didn't get to explore much more on it, not sure what it is, but seems weird that it was just hanging there? That's today's work.

Also review the previous owner's mileage log it was only driven 3 times last year, so yeah, it has been sitting around a lot. So probably would benefit from the tune-up coming its way.

I'm not an expert on fuel trims, but LTFT I believe should be low single digits.

O2 sensors rarely throw a code except for short to ground or open circuit. If the sensor has fallen out of spec, the computer likely won't realize it. I would sort out a tune up and other issues that arise first before replacing MAF and O2 sensors.

The fresh air snorkel isn't really a requirement. My car ran fine without one for years. Same for a loose air box, unless you mean the cover is loose.

If any rubber lines are hard, mushy and goey, or show cracking, it's time to replace them (in this case it's probably all of them).

Now that connector is a prime suspect. Investigate that first.

+1 for ordering silicone lines. I know for sure you need at least 7ft of 5mm ID (not 3/16").

Same as me, my knowledge just tells me that number is too high and like you say should be low single digits.

I am reluctant to start dumping money on sensors right away unless I know for sure.

Going to check all the lines and that connector today, an open connector doesn't seem right either way. And I will probably just buy vacuum lines and replace them, just need to know what ones and how much.