Well I've had my car for about 2 weeks now. '97 Z28 A4, bone stock when I got it, 26,000 on it Anyhow, I have been doing some reading on here, and I have a few questions for you seasoned F-body veterans.

My goals with the car, being it is my only car, is a reasonably quick daily driver. I'm talkin basic bolt-ons, and I might buy a set of DRs for track visits. Anyways, I have already done a K&N FIPK, bout a week ago. I was driving home today, and threw my first SES light (welcome to the club, eh?) I'm thinking that perhaps the oil from the K&N got the MAF dirty, or one of my clamps came a little loose, perhaps. Also, it was raining pretty bad on the way home, will my car throw a code if some water makes its way into the intake? I'm gonna re-tighten all my clamps, clean the MAF, and reset the computer. If that doesn't do it, what else should I try?

Also, I have a few general questions. How can I tell which rear-end gears I have? I don't know if its the 2.73s or the 3.23s. What exactly does the throttle body bypass mod do, why does it give power, and how do I do it?

Thanks alot to anyone who gives a helpful reply. I have searched a few times for this kinda stuff but I have a hard time getting the search to bring up stuff that's relevant to my questions.

First of All welcome to pain and joy of owning a F-body. Well I am pretty new At this site but I did learn few things by reading the Threads and guys here's helping me out. They are great. Well for the SES light my 94T/A A4 did it, to me coming home from work, it was raining hard. I managed to go over some Puddles and water made it's way up to the intake and air pump. Also fried my EGR valve that's why mine threw the SES light. As far as I know the throttle body bypass mod gives you power by running cool. All you do is bypass the coolant throw underneath the throttle body and that keeps it cool. Which allows cold air to go in. Cold air equals more power. Someone can correct me if i am wrong. Goodluck

Get her scanned. See whats going on before you start throwing money at it.


Check your RPO codes, GU2 = 2.73 GU5 = 3.23


It stops coolant flowing thru your throttle body by attaching the hose on the right side of the tb to the heater inlet hose on the left side of the bay.


I guess it's just a matter of opinion, ive seen dyno charts that show a gain of 2hp and dyno charts that show none at all. In theory it gives power by keeping the TB cool, air flowing through the TB will not warm up if the TB itself isnt warm. Cooler air = more dense.


Read above.

1. Get it scanned, as noted above. Do not guess.

2. This dyno test shows a 6HP gain for the TB coolant bypass:
http://www.ws6.com/mod-8.htm

Well, after working on my car for a little bit, I have ran into a new problem. I reset the computer by disconnecting the battery, and now my CD player is "locked." I just bought the car a couple weeks ago, and I don't know the previous owners code. Also, I got it at a dealership, so there is no way for me to contact said previous owner. Anyone know how to fix this, or do I have to take it to my local Chevy dealer and pay to have it reprogrammed?

1. Press and hold presets 2 & 3 for about 10 seconds until the first 3 digits of the display code are displayed.
2. Write the numbers down.
3. Press the AM/FM button, write down the next 3 numbers.
4. Call 1-800-537-5140, when asked, enter 202107 (if this doesnt work try 139010 or 06010), press the # button and enter the 6 digit code from the radio, you will get an unlock code, write it down.
5. Go back to the car, press the HR button and set the first 2 numbers, then
press minute button and set the next two last numbers, press AM FM button, SEC should be displayed, turn on radio.

To remove customers code, repeat step 5. you should see ---
on radio face, the code is now out of the radio.

try that

as for your SES - ive never thrown a code from my K&N and re-oil it every couple months- in fact dont really know of anyone that has-

water- ive accidently driven through a puddle in which my intake was well submerged and car bogged and i of course quickly parked it to dry- but never through a light.

just go to autozone and have it scanned for free- and be very careful with the MAF- they are expensive to replace

I can't thank you enough for the advice! I fixed my radio and it took about 5 minutes - local Chevy dealer wanted $30 to reprogram it. I am planning on getting it scanned within the next day or two to figure out the SES light. If it is the MAF, I will probably just go with the one from Granatelli Motorsports, unless anyone here has heard badly about them.

STAY AWAY from the granatelli MAF. You wont need a large one for a LONG time, and without tuning there will be no gains from it. Go ahead and run any future mods by us ok?

Oh, and welcome

Copy that!! I am new to the 4th gen world, had a '68 Firebird 350 for a while but it is no longer in my posession...no MAF or OPTI to worry about on that old dog.