Car running rich. How do I fix it?

[coffeeman885]

I am pretty sure that my car is running hella rich. I is putting out a really strong exhaust smell, gets horrible gas milage, and the end of my muffler is sooty. What are my options for fixing this? I can't do anything to my computer, can I?

[Alphius]

Fix the problem causing it to be rich. They weren't like that from the factory.

Do you have any check engine lights?

A common failure that won't always light a CEL is the coolant temp sensor. Might want to try replacing that if it hasn't been replaced recently. It's a pretty small, cheap and easy fix.

[coffeeman885]

Does anybody have the part number for the coolant temp sensor? I am having no luck with the parts catalog that I have.

No, there are no CELs.

[Alphius]

The coolant sensor is OEM part number 22630AA041.
It looks like it's nearly $20 at subarugenuineparts.com and they charge a lot for shipping. You might want to try searching that Subaru part number at RockAuto.com, it's a little cheaper there for SMP TX84 ($17 and cheaper shipping) and you can use 5% discount code 93128304867261 which expires on the 24th of this month.

Where are you located? I bet it would be fairly easy to find out what was wrong if there was someone near you that had a cable to scan your ECU. I feel that it could also easily be your O2 sensor but those are much more expensive, so it's worth a shot on the coolant temp sensor I think. Has the O2 been replaced recently? When was the last time you did a tuneup with spark plugs, spark plug wires and air filter?

22690AA150 is the O2 sensor part number. $110 at SubaruGenuineParts and $47 on closeout at RockAuto (damn good price!). These are direct fit parts with the correct plug on them. A Universal might be a little cheaper but you'll have to splice the connector in.

[coffeeman885]

I'm in northern VA. The O2 sensor hasn't been changed. The air filter has either been getting changed or cleaned (finally broke down and got a K&N though I don't know if I like it) once a month because I rallycross it. I just drove it to get some food and now it is making a "crunchy" sound/feeling in the pedals as I take off. So who knows what new hell I am going to get into when it stops raining and I get to take a look under the car.

[Legacy777]

Can you elaborate what you mean by a crunch sound?

[coffeeman885]

Bit of an update. I think I figured out my "crunchy" problem. My engine mounts are shot all to hell. You can hear the headers smack the skid plate when I start the car. I am changing them next weekend. I will be changing the coolant temp sensor, o2 sensor, and spark plugs as well.

Would it be a good idea to run seafoam though the engine to try to burn off some of the carbon that has undoubtedly built up? Should I do it before or after I change the spark plugs? Which vacuum line works best for sucking up the stuff?

[DD50]

I have the same problem with mine. I don't have any CELs. I changed the O2 sensor a few months ago and did a full tune up a few months ago as well. Same with the coolant temp sensor. I was told by a mechanic friend that one of my cats is possibly clogged a bit but its hard to say

[Legacy777]

Bit of an update. I think I figured out my "crunchy" problem. My engine mounts are shot all to hell. You can hear the headers smack the skid plate when I start the car. I am changing them next weekend. I will be changing the coolant temp sensor, o2 sensor, and spark plugs as well.

Would it be a good idea to run seafoam though the engine to try to burn off some of the carbon that has undoubtedly built up? Should I do it before or after I change the spark plugs? Which vacuum line works best for sucking up the stuff?

If the engine is running ok now, I'd run the seafoam through and then change the plugs.