Now i did it O2 sensor

Swapping out the o2 sensor and of course snapped one of the nuts off on the downstream sensor. There is "mebbe" a 1/4 inch left when I put the sensor and gasket back on.

What are you guys doing when that happens to you (don't tell me I'm the only one....)

 

I would spray penetrating oil on broken stud and then clamp on vise grips and remove stud. Goto store and buy 2 new bolts.

 

Is it a stud? Seems like its welded to the flange... I put penetrating oil on the night before I did the part swap,

I should state that this 97 grew up in Monterey and had lots of salt vapor exposure. Light rust everywhere.

 

I actually just used one stud and it sealed up fine with the gasket.

 

Until I had a new exhaust installed. Which is stock but nice.

 

Funny you said that. I put it back with just the one and it seems fine

 

So, fun fact,

Even after swapping out both sensors and clearing the codes, it came back after one day. (P0171).

New air filter, new up and down stream sensors, vac lines look soft and uncracked, and I did a very thorough MAF cleaning with the stuff CRC makes for the job.

Kinda stumped what else to check at this point.

 

P0171 System Too Lean Bank 1

Well, you've figured out it's not the O2 sensors!

C'mon...you can't be stumped. You haven't really done much yet! "I've tried nothing and I'm all out of ideas!" (I kid, I kid).

Here's a decent list of culprits:

https://www.samarins.com/diagnose/p0171.html

You will want to verify it's not a vacuum leak first. Those are really the most common. Google on how to find it. You can get the car running and spray stuff here and there and listen for a change.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If that doesn't yield anything. If it were me...I would pull the throttle body and give it a really good cleaning. Then I would try a new IAC (those get super gunked up).

For everything else, you'll need to start figuring out how to rule things out one by one. Or if stuff just looks too worn...replace it.

But don't get frustrated...that list is long. Pick the most obvious to start with. This is one of those codes that really sucks as it is a catch-all.

Edit...also...replace the MAF. It's probably due and is like culprit #1 or #2. Cleaning doesn't always help.

 

And exhaust leak would cause the system to run lean. When were plugs/wires/coils done?

 

Another thought, check or replace PCV valve.

 

Good suggestions and chastisement- I will get back to to it

I am smelling a slight leak when pulling uphill, will have to check on that. I got the rig last fall and haven't touched plugs wires coils...

Did that one, forgot to add it.



You guys are right,

Need to quit whining and get back in there.

 

I wouldn't think plugs or wires just yet. I ran my rig until it was missing terribly and getting ignition codes (got 175k out of my original plugs!)...but didn't get any fuel mixture codes. But of course don't discount it...and if you feel they've run their life...it still doesn't hurt to replace. Except the coil packs...those run a loooong time.

 

Was ready to throw in the towel and have a shop do it- buddy sends me info on a shop where his friend just got a great job done.

Call up and the dude is a total dick- " who's your general mechanic, they can address codes"

Told him I'm DIY, I can hear the snark ooze out as soon as I said that. Call gets worse- told him theres' an exhaust leak- "how do you know" "I can smell it, its been there for a while and I broke a stud off one of the O2 sensor mounts since then" "well that's where your leak is then" Finally he says "If you wanna drop it off and leave it all day I might be be able to look at it"

Hate mechanics sometimes.

For reference- I work on equipment for a living, have done so for over 20 years, from butcher shop meat saws to organ transplant cell sorting.

I'm not an idiot, but I do know there are times to hand it off to someone who specializes in a field. And I get this.

 

Yeah. STAY AWAY from that shop.

So one thing you can do...is take it to the Toyota dealer. Honestly the dealer usually has guys who are tops on diagnostics.

Then you can get an estimate, refuse the work, pay the diag fee....and just do it yourself.

Or ask around where a good ASIAN/IMPORT shop is. Those guys often don't touch anything but Toyotas/Hondas.

 

And your buddy recommended this shop? They do sound like total d#cks.