[Andrus]

Hey all. I've been browsing your forums with my issue and am not sure what I should try next.

A couple weeks ago I cleaned some corrosion off the postive terminal. I reconnected and the car would barely idle and would almost stall accelerating from a stop. I read about throttle body issues with computer resets so i cleaned the throttle body and changed the plugs (just hit 100k miles). It ran great after that but then a got the CEL, ABS and VSC lights. Parts store ran codes and got P0441. Changed gas cap and a very dry hose from the charcoal canister to the line running to the from of the car. No change. Got my own wifi adapter and read the codes and I have P0171 in addition to P0441. So I'm not sure what I should try first?

 

[RAVN4RED]

...A couple weeks ago I cleaned some corrosion off the postive terminal. I reconnected and the car would barely idle and would almost stall accelerating from a stop. I read about throttle body issues with computer resets so i cleaned the throttle body and changed the plugs (just hit 100k miles). It ran great after that but then a got the CEL, ABS and VSC lights. Parts store ran codes and got P0441. Changed gas cap and a very dry hose from the charcoal canister to the line running to the from of the car. No change. Got my own wifi adapter and read the codes and I have P0171 in addition to P0441. So I'm not sure what I should try first?

First thing to thoroughly check is the battery. The corrosion of the terminal indicates something is up. Battery going bad can cause lots of gremlins and turmoil, and they can go bad in 3 or 4 years.

Also update your profile and signature line so we know what year car you have and what state you live in if problem is climate related. My personal theory is the 2006-08 I4 engines (if oil burners) throw more codes than the average bear, so verify oil consumption.

Otherwise, welcome to the board and hope you solve the codes!

 

[Andrus]

Thank you RAVN4RED for the reply.

I've updated my profile (2007 model 4 cyl that's been in Houston, TX its whole life).

I did fail to mention that I did have to replace the battery a couple days after I cleaned the terminal. It also was low a quart of oil at the time I checked when all this initially occurred, so it could be burning it and I'll continue to monitor.

 

[RAVN4RED]

Yeah, the climate in Houston would take a toll on battery life, but you likely eliminated that with a new one.

Basically, how is your car running now? You did a lot of stuff to it, is it just throwing codes or is it running badly?

Next, you're down a quart of oil--in how many miles? You know Toyota has an extended warranty on your car to test for excess oil burn, right? Some have reported they will even fix issues arising from this excess burn like emissions systems failures. You should come up to speed on warranty for sure, and get it in for a test if you're burnin'. You are covered until 10 years from date of manufacture, for you sometime in 2017.

Okay, I've not had the codes you mention, but I'll throw out some things I have learned from this forum. I've been preparing for the day when my turn comes. But not an expert AT ALL, like some of the fine folks here.

If you haven't done so, spend time reading this sticky link from up top, vast info in there:

http://www.rav4world.com/forums/99-4-3-mechanical/85765-check-engine-light-vsc-4wd-lights-explained.html

Here's some other factoids I've picked up:

* after disconnecting the battery sometimes the RAV will throw codes and sometimes the ECU needs to relearn behavior and eventually straightens out.

*sometimes the codes need to be cleared with a device, even if the problem has been fixed.

*throttle bodies and MAF sensors are picky units and can cause a code if you tweaked something wrong while cleaning.

*codes thrown by the RAV can indicate a lot of different things. P0171 (Lean condition) could be a variety of things, as could P0441 Evap system problem.

*quite a few people have reported after throwing a lot of parts at the codes, it turned out to be the air/fuel ratio sensor! Consider starting there.

*always use Toyota parts (Denso) when replacing sensors.

Let us know how it goes, hopefully the pros here pick up the trail and help you troubleshoot it.

 

[Andrus]

Thanks for the reply again.

The car runs well now. No obvious problems.

I use synthetic oil so I don't change it as often as conventional...so I'd have to say that 1 quart loss took about 6 months. I do remember getting the recall notice but took little note of it at the time since it made reference to losing a quart in 1,200 miles. I'll have to look into it further.

I've read most of what you referenced. I think cleaning the throttle body might have ultimately resulted in my codes as they do come back even if I reset with the scanner. I'll wait and see if they persist before I replace any sensors.

 

[FixIt]

P0171 means the engine is getting too much air that is not measured by the MAF sensor. P0441 is a fault with the EVAP system.


Check closely all the vacuum hoses under the hood. Chances are you knocked one off during your service. There will be a purge line connected to a solenoid and that solenoid will have a line going to the rear of the vehicle. It should be ganged together with the fuel line.