LoCore

A friend has a 2003 Tacoma w/TRD supercharger on it, and has recently been getting check engine lights. He took it to the dealer today where a code P0171 (lean condition) was read.

The friend was told that the problem was a dirty MAFS since he was using a K&N filter, and wanted to charge him $80 to clean the MAFS. I told the friend that we would check it ourselves. We did so, and found the MAFS completely clean. Our conclusion was that the dealer did nothing after reading the code and resetting the CEL.

This is the first summer that the friend has had the truck. We were wondering if the warmer temperatures, combined with the altutude (5000'), was contributing to the likelyhood of a lean condition being thrown.

SO... any suggestions on what to tell my friend on how to proceed? Are lean condition CELs a known problem with the supercharger on the 2003 Tacoma? And if so, is this anything to worry about? Is this something he can get the dealer to care about?

Thanks for any advice you can share.

Weasy2k

yea thats normal....and expected...all s/c trucks need to be modded to make up for the increased airflow....larger injectors and fuel pump are needed along with a piggy back computer to control it....

try taking off the k&n (if its the whole intake kit) and putting back stock intake. Just to restrict some air...but its what happens...

Gadget

The most likely problem is a vacuum leak. Give all the vacuum hose a good once over.

If the supercharger was recently installed, the most common mistake that quickly throws a check engine light with a lean code is an improperly installed throttle body gasket. Check that.

If you do not find anything wrong, then have the dealer do thier thing. They should look up the diagnostic proceedure that code recommends and preform it under warranty. If the supercharger was not dealer installed and it turns out to be some kind of installation error then you might have to pay for it. If it was dealer installed then they should cover it under warranty and if it is a supercharger issue they will bill the warranty work to TRD instead of Toyota.

Gadget

www.GadgetOnline.com

LoCore

Thanks for the quick responses. We'll get to work on the hunt for vacuum leaks.

BlueTrane

From my experience the newer trucks don't need fuel mods and will actually run rich under normal conditions. When I first had my S/C installed I also got the LEAN code. I checked over all the boost/vacuum hoses and realized the dealer had hooked up everything all wrong.

Check those connections and just reset the code and you should be OK. Also, the instructions say not to install the IAC on the newer trucks but I was experiencing huge problems without it. I don't know where it goes on the Taco but its a little white valve coming out of bottom/cabin side of the throttle body.

Do a search for IAC and see the problems ManyMods and I were having.

Good Luck!!

BT

Weasy2k

my apologies i didnt know that...but now i do =]

thanks!

Gadget

No matter what year truck you have, if you install the fuel mods and it runs rich when it is not supposed to it is not tuned correctly.

Gadget

www.GadgetOnline.com

Rayday81

Make sure you take clean the MAF sensor real good like with a Qtip or something. I got that same code on my '99 and it looked clean, but when I ran the Qtip over it, ther was some dust. Then I reset the codes and the check engine light hasn't come on since.