Warning Lights

[MysticGold04]

Yesterday, I changed the spark plugs in the Highlander, and I also cleaned the throttle body assembly (as well as I could) Success... then I decided to pull the MAF and clean it as well. I did that, let it dry and re-installed very carefully. Now I have the Check Engine, VSC, and TRAC OFF illuminated. I tried pulling the EFI fuses, but to no avail. Later tonight I'm going to pull the code with my SGII, and disconnect the battery I guess... but I surely could not have damaged the MAF could I? I used MAF cleaner.. specifically for it... and was extremely careful about removal/installation.

I have double checked the intake hoses, etc, all seems good. Any other ideas??? I suppose I'll try to test the MAF and harness as well.

BTW, no lights prior to the MAF being cleaned.

 

[StevieC]

Disconnect the battery for 20 minutes and reconnect. Then see if the lights go out. If not then scan with your scan tool and see what shows up. Most likely a coincidence because the TRAC OFF has nothing to do with a MAF.

 

[MysticGold04]

I did some searching on the web last night, and found that usually when you get a DTC code, all three light up for some reason, not really sure why because VSC is Stability control, and TRAC OFF is a manual indicator that you've turned traction control off.

I will pull the battery tonight when I get home tonight. Hopefully everything just needs reset. Ugh.. I hate disconnecting the battery cuz I loose the trip meters!!!! The trip meters are my quick glance at my OCI! Although it does have a 'Maint Required' light that comes on.

 

[StevieC]

Buy a Hyundai I never loose my trip meters and I disconnect my battery all the time to do stuff.

 

[mechtech2]

We can knock a part that we are not actually working on.
Maybe this is what happened.
A reset of the computer is a good idea, although 20 minutes seems awful long.

 

[StevieC]

20 minutes will ensure no more power in the system. 30 Seconds may not be enough and most people can wait 20 minutes...

 

[bepperb]

The TRAC and VSC lights will come on anytime there is a MIL light on this vehicle. The vehicle puts itself into "limp home" mode. It'll do it is the gas cap is loose. It'll do it for anything.

It doesn't make much sense to speculate on the problem if you have an SGII or other way to read the codes. I'd read them before the reset, for a good post-mortem on what happened.

I have the same, and I've used the CRC MAF cleaner. I assume you have the... well... for lack of a better desription a snorkel type MAF sensor with a long tube? I shoot it right up there and haven't had any problems.

Best of luck. I'm interested to hear. We're sure a vacuum tube wasn't pulled loose, that happens all the time with the V6's. That or an evap system tube.

 

[MysticGold04]

I'll pull the codes just to see what they are. I actually removed the two screws from the MAF and removed it from the airbox. I laid it on its side, on a rag, and gave it a good shot of cleaner. Let it dry, and re-installed. Started it up, and on came the lights. I double and triple checked for a loose Vac or Evap hose, but all was secure. Hopefully I can reset it and it will be happy again. It sure runs nice now since I did all that cleanup. I also added some MMO to the gas... MMO smells good!

btw, bepperb, a little OT, but have you ever changed the serp belt by chance? I have a gatorback to put on, it just looks a little intimidating.

 

[MysticGold04]

Pulled the code... P0300 - Multiple misfires... those must have been from the TB cleaning and MAF... Interesting... anyhow, I cleared the code and the lights went off. We'll see if they come back, since they didn't come back right away.

 

[bepperb]

Well, that's good news. No, I haven't done the serp belt yet, I'm only at 61,000. I'm sure it won't be that bad, and you'll be much more flexible when you're done.

All I've really needed to be done was the temperature control knob soldering fix, a remote starter, the hitch/wiring and fogs.

 

[PT1]

Mystic: Next time pull the TB assembly completely off and give it a good cleaning. The 2AZ TB is easy to get off and on and will give you a long time between clenings if you change the air filter at 20,000 miles versus the 30k Toyota recomends. I usually remove and clean the whole thing including all the plastic duct work and air box. Just label all the hoses & plugs and you are good to go. I change out the PCV at the same time. If you wait until 125k you can do the spark plugs easier with the TB off as well. I see you are at 94k. You might want to do the TB & plugs at 125-140k. I did my last 2AZ plugs at 125k and they were fine. If I hadn't bought new ones I would have put them back in.

 

[MysticGold04]

Originally Posted By: bepperb
Well, that's good news. No, I haven't done the serp belt yet, I'm only at 61,000. I'm sure it won't be that bad, and you'll be much more flexible when you're done.

All I've really needed to be done was the temperature control knob soldering fix, a remote starter, the hitch/wiring and fogs.


I just had to tighten the control knobs, as the wires were still soldered to the board well.. still every once in awhile, the AC gets warm though. I might have to revisit it.

 

[MysticGold04]

Originally Posted By: MysticGold04
Pulled the code... P0300 - Multiple misfires... those must have been from the TB cleaning and MAF... Interesting... anyhow, I cleared the code and the lights went off. We'll see if they come back, since they didn't come back right away.


Just wanted to update... no lights are back. Must have been the all of the crud that caused the misfires. What I should have done is clean the TB and MAF before changing the spark plugs, but hindsight is ALWAYS 20/20