tuning and aem wideband help

jw_55_55 · 01-06-2008, 06:46 PM

Ok ill first start off with ...i just installed a T3 manifold, t3/t4 BB 50 trim, Turbonetics external wastegate(MARK V something and it is recirculated),GM maf, ARP headstuds, denso 660's, web cams(hks 272's basically), prothane motor mounts, rebuilt head with 3g lifters, SAFC2, Maf translator AEM wideband!

-Now the wideband i got was used and the guy said it was working before. After I started the engine it turned on and wouldnt give me a reading....it said i was running lean! so my question is how do i know if its a bad sensor or if im really running lean? I think i should be running rich and so does the guy who helped me with the install!

- Now to tuning...I have never tuned and or logged my car before so im basically clueless on where to start! yes i have read some of the how to's and they make some sense to me but i would just really like to know how to get a rough tune so i feel ok to drive it home then to a professional shop for real tuning. another question is do you think i should drive it aropund a little bit to break in the cams and head before bringing it to shop to tune?

thanks in advance

Eastwood95 · 01-06-2008, 07:26 PM

Apexi Super AFC For The Eclipse/EVO

RRE's Super AFC Setting and Adjustment Tips

I would highly recommend breaking in the new parts for at least a few hundred miles before attempting a max performance tune. Do you have a logger or just the SAFC/Wideband combo?

jw_55_55 · 01-06-2008, 07:50 PM

i do have a logger and how would i know if my wideband sensor is good or not?-

architechnik · 01-06-2008, 07:52 PM

With all the modifications you've done, it will be difficult to know whether you are running lean or rich, especially if you haven't previously set the GM/MAFT prior to making each modification and noting the changes.

Was the AEM reading lean continuously or just during the first few moments of starting?
Mine reads lean for the first few moments before the sensor heats up, but then levels off to normal idle operation and minor oscillation. The newer AEM units don't require any calibration, although some older O2 sensors do require it.

Have you tried any short pulls to see if the vehicle changes between closed loop and open operation?

jw_55_55 · 01-06-2008, 07:56 PM

all i have done is started it and let it run for like 4-5 minutes!! and it just reads past the lean so i havent even tried to do anything before i can get the wideband to read not lean or atleast read something....

architechnik · 01-06-2008, 08:29 PM

Getting the vehicle to read the correct setting is going to take more than 5 minutes of idle. If it reads slightly lean, you'll be fine. I don't suggest revving the engine to see changes, as that is not what it is built for.

Make sure the turbo is not turned up, keep it around 10-14lbs. Take it around the block and during acceleration take it up to about 55% throttle until 3.5-4k in 2nd. If the O2 reads the same the entire time, then it is not working. If it goes to --- (extremely lean) during any point stop acceleration and let it idle for a slight cool down before continuing home. If the wideband goes to complete rich, as likely it will, then you'll be fine.

If it went lean during this test, then you've got a problem, whether it's faulty injectors, wiring, MAFT, or any of these, you'll have to start a long trouble shooting process.

Quick Note: Remember that it takes time for an ECU to memorize optimal cruise operation and will only result from extended operation without removing battery power. Electronic tuning should be done before new settings are memorized.

jw_55_55 · 01-06-2008, 08:53 PM

so do you want me to let it get to temp first or no??

architechnik · 01-06-2008, 09:00 PM

Yes. Warm it up for about 3-5 minutes before taking it out. Make sure the temp sensor gets to that first notch past "0". If you have a logger, you can monitor the temp and you're good when it reaches about 85 C or 190 F. It would be a good idea to have the logger hooked up and tracking everything on this little jaunt, as it may show some other things that you would not otherwise be aware (knock, ecu readings for rpms, etc.)

If the actual sensor is dead, they're about $70 for a new replacement. From the description, this is not what is sounds like, though.

jw_55_55 · 01-06-2008, 09:10 PM

alright thanks for all the help....ill get back to on here tomorrow and let u know what happened

TurboTJ · 01-06-2008, 09:23 PM

I recently went through some issues with my AEM wideband. Turned out to be that the aem was reading incorrectly that I was rich. To figure out what my problem was, I went to a local shop and had them connect their wideband up. Because of the cat, theirs was reading a little lean but confirmed that I was running correctly.

Correct me if I am wrong, but shouldn't your O2 volts be staying below .5 if it is running lean? This could also help you figure it out.

Eastwood95 · 01-07-2008, 11:38 AM

jw 55,

Where is the AEM o2 sensor installed?

Architechnik gave you some pretty good advice to check the operation of your sensor, follow that and let us know....

TurboTJ,
Is your sensor installed after the cat? If so, that would definitely throw your readings off....
The sensor should be installed pre-cat to get the correct readings. If you don't have a cat, then it wouldnt really matter....

I dont quite understand where you get .5 volts from, and are you talking about WOT Volts or Cruise?

architechnik · 01-07-2008, 12:10 PM

Reading the volts depends on which unit you have and what setting you have the auxiliary output for the AEM. If you have the aux set at p4 for the newer units, which will emulate the stock O2 sensor, then is will be reversed 0-1v. If the voltage is below .5 then I believe it will be running rich, not lean. But then again, it depends on what setting you have that aux output on.