Leaning Out at 3K RPMs

[pj23322]

Hey guys, I've got a 1998 GST (auto if that makes any difference) and within the last couple of weeks, at around 3,000 RPMs, I'm showing a very lean condition on my autometer A/F gauge when I normally would see the richest value. By very lean, I mean the first or second red LED is lit up when I'm at 3K. This happens if I have my foot down on the gas pedal or even when I'm cruising on the hwy between 75-80MPH. As soon as I bring the engine speed below 3K, the A/F gauge begins to cycle again. When I get on the gas, the A/F meter does light up the last green LED for about a second and they it slowly lights it way back to one of the first red LEDs. My autometer boost gauge shows I never go over 12-13 psi of boost when I'm at WOT. I originally had an intake, hard intercooler pipes, BOV, and a boost controller that I had been running for almost a year, but I took them off and put all the factory intake and intercooler pipes, even replaced the front o2 sensor, and I'm still getting the same problem. I am still using the stock turbo, but I do have a high flow exhaust manifold, ported o2 housing, RRE downpipe, RRE hig-flow cat, and Greddy catback. I have a FPR which I have set at 48 psi. I haven't been getting any CELs. Any ideas? Sorry to write a book...

 

[tom04841]

No offense, but that A/F guage is nothing more than a light show.

If you really want to know what the car is doing, get a logger so you can record what it is doing and post it up so we can do more than just GUESS.

I wouldn't put too much faith into your A/F guage