Check Engine/VSC/Trac off light 2004 V8

[yotanoob]

Hey y'all,
Ran into a little problem this morning on my way to work. Was driving down the freeway and my Check Engine, VSC off and Trac off light all came on. Unfortunately when my car got broken into a month ago they stole my OBD2 Scanner :50cal:. So trying to pinpoint the problem before I drive home from work. Yesterday I did a few maintenance related fixes to the truck. Replaced battery with Optima Yellow Top, replaced PCV valve, changed oil used Amsoil 5W30 Full Stnthetic Signature Series with BG MOA. I also added BG 44k Fuel System cleaner to a full 20 Gallon gas tank. The truck run fine I just would like to keep the mileage as low as possible with the lights on. Has anyone had this issue when changing the PCV valve or changing oil?

The truck is a 2004 V8

 

[yotanoob]

**** Double Post Please Delet****

 

[RonJR]

Take it to Autozone/O'reillys and have the codes scanned, and go from there. Most CEL codes will also light the VSC off and Trac off lights. The VSC and Trac computer algorithms rely on known engine performance, so Toyota shuts those functions down if the engine isn't running up to spec.

 

[sean81]

Gas Cap?

The gas cap being loose is a common source of this. Check your cap, if its loose you can tighten it and remove the neg lead on the battery to clear the code. My 07 needed a new cap, even though I would tighten it when gassing up it was working loose. When the cap is good you tighten it till it clicks then you can turn it left freely for an 1/8 of a turn till you feel it catch. New OEM cap was $25ish on ebay/amazon.

 

[Gavin S.]

I had the same symptoms. I got several emissions related codes on my generic scanner. I tried the gas cap replacement and was still getting the lights a few hundred miles after resetting them. Further research revealed that it can also be caused by some valves related to the charcoal canister system that recoup unburned fuel or some such. I think there are 3 valves that can be the culprit. I haven't followed up beyond that, but if you do a google search with the codes and 2004 4Runner in the search line I'm sure you'll see what I'm talking about. Try the gas cap first, though. It's the easiest.

 

[yotanoob]

Thanks for all the suggestions.

I bought a new fuel cap, not the culprit although it needed replacing.

Broke down and bought another OBD2 Reader, P0031 code popped for for S1B1 Heated 02 Sensor. Have a Denso plug on order it'll be here tomorrow, lets hope thats the only bad sensor for now. I am going to pull and test the remainder and may just end up doing the rest.