Husband has a 2001 IS 300. He added a SRT intake a while back and modified the computer as well. A few weeks ago we had to buy a new battery and when we got it the installer said something was draining power, but he didn't know what. Now the check engine light is on and the trac off light is flashing. I read on another thread some solutions to try (intake sensor loose, dirty MAF sensor etc). His intake has a heat shield already and he just replace 2 or 3 of the O2 sensors. Any ideas???
We would like to keep this car but don't want to have to keep dumping money in it to keep it going.
Also pardon my lack of car knowledge if I have left anthing out. If any other info is needed let me know and I will post.
Thanks so much!!

Also we have a code reader but it will not read anything. It won't even power up the reader!!

 

sounds like something maybe grounding out somewhere.. Tell him to recheck the wiring on the SRT race ecu he isntalled. Something may have come loose or is touching something its not suppose to. Tell him to go over his installation instructions and he can reset the computer by leaving the negative terminal off for roughly about 2-5min.

 

Is the car on when you plug in the OBDII reader? My reader doesn't work unless the key is at least in the on position (maybe ACC position). Were the o2 sensors replaced before or after the CEL (Check Engine Light)? Worst case scenario, go to autozone, have them read the codes for you, and report back.

Try to think about what was done just before the CEL appeared. It could even be something as simple as a loose gas cap or hose. Recheck your installs...especially the o2 sensors and the intake + r-ecu.

What other aftermarket parts have you installed? If parasitic draw is >70mA/.07A, you need to figure out what it is. You will need a multimeter to do this. With the car off, disconnect the negative battery cable. Put your multimeter in the 10A mode (make sure your leads are in the proper locations on the multimeter). Attach one lead to the neg battery cable terminal, and the other to the negative battery post (it doesn't matter which goes where). I was told to leave them attached for 5 minutes to get a proper reading. I rested a rubber squeegee on the lead to hold it on the post. I clipped the other lead to the cable.

If you see that the parasitic draw is >70mA, I would start by disconnecting aftermarket parts from their power source one at a time while checking parasitic draw. In my case, I had a back up cam attached to what I thought was a switched fuse via add-a-circuit. Its total draw with the car off was 160mA. After changing the power source, draw dropped to 50mA, which is OK.

If you can't find a specific part causing the problem, you need to start pulling fuses one at a time. I would start with the fuse blocks in the driver & passenger kick panels before moving into the engine bay. When you find the problem fuse, you need to find out what is on the circuit. Alternatively, if you have a BLOWN fuse, you can plug it into another fuse's spot and check for draw at the top of the fuse (using the same 10A setting). When I tried doing it this way, I found it to be a PITA due to cramped work space.

Note: when using the multimeter, make sure you have the probes plugged into the proper ports, or you could fry the multimeter (or at least its internal fuse).

I hope that helps.

 

You had someone install a battery for you?