I cannot get my low trim to stabalize at all since my MAF translator install. No matter what I adjust the translator to, with the car at idle, the low trim runs from 81 to 139 and back again. Could the MAF be going bad?

Okay, I'm stepping out of my backyard a little here, but I think the 02 sensor would be at fault in this case. If the ECU can't get a solid reading from that little guy, it'll constantly be adjusting to an unstable reading, causing the sweeps you speak of. Anyhow, that would be my first course of action.

Thanks for the input Goat. Your logic make sense. Looking through the archives, I believe the general idea is get OEM Mitsu or Denso and stay away from Bosch. Anybody have any comments here?

Tonight I swapped in another MAF I had and the trims may have calmed down some. I'll check the trims again on the way to work tomorrow and see if it the same.

You could also try turning the MAF. With GM MAFs and reducers the thing can be turned to where it won't see airflow at low flow rates.

not to steal a thread but why do you say stay away from bosch? just wondering.

I tried turning the first MAF and it made no differance.

Is there a orientation it's "supposed" to be? Looking on the internet, everyone seems to have different setups. Mine's in a draw through config so it's hard to find examples, most run blow through.

The second one does vary some idling, 110-127. But nowhere near the first one where it would just cycle up and down the range 81-82-83 etc (at the speed it took to read those numbers). So I'll try rotating it and see if I can stop it completly

With this MAF all the trims have seemed to stabalized lean, Hi 102, MID 106 and Low 110-127 so I need to bump up my base setting. I'm getting about .88 at WOT.

It is supposed to be clocked so that the rectangular portion of the sensor is positioned so it is at the 'top'. having said that, a lot of people never have a problem 'kicking' to the side.

I like to 'kick' it, sure. That's why I have my license plate frenched into my tailgate on my s10 bagged pickup at a carazay angle. But then again, I'm a rebel who follows his own path, not some conformist who 'plays by the rules'. So all you suckers out there who 'walk the line' and 'play fair' can eat my dust while I billy bad-ass it up, shaking and baking my way into and out of wacky situations. That's just me.

Ok, somethings not right. Tried to do so WOT pulls. The car was bucking like crazy and I thought it was fuel cut. But it bucked 5-6 times. So I pulled the log. The O2 reading at WOT are not right. It's put out random .02V at 100% TPS. I was thinking it was fuel cut, but there's still injector pulses, so it can't be fuel cut. I also noticed a black cloud after one of the bucking.

Here's some logs:
LOG Graph Downloading the pic will make it look better
LOG DATA

What do you guys think? I'm thinking Goat mighted of guessed it right with the o2 sensor.

Or perhaps the Goat has sabotaged all who oppose him. SUCK ON THAT, SWEETHEART!!!!!!!!!

Maybe all my ramblings are a huge decoy to lure you into a sence of false confidence!!


Maybe we should just line up and settle it!

Wait....that's right....you're NOT GOING!!!!




EDIT*****
I see you did sign up!
Let's see who has the best junk!

that would be me

Sorry...saw "Goat" and jumped to the wrong conclusion!

I stand by my previous taunt!

I'm right here....

I hear ya...

You got it, pal! Oh, wait.... you'll prolly not even make it in the pre-quals, so I guess you'll have to wait until your car gets some bigger yams. Darn.

In all seriousness, I'm excited to see what the car can do with this itty bitty turbo. Not sure what exactly setup I'll be running for fuel/boost and all. We shall see....

In all seriousness aslo, I'm just busting your balls to get you to go. Misery love compary!

Gap your plugs to .026. It sounds like spark blowout to me.

I was thinking along the same lines. You may also want to upgrade the plug wires if they are still the stockers.

Plug wire are magnacore and in decent shape.

I put a Bosch o2 sensor in, Mitsu could get an OEM one until next week. Things were great for about half an hour. Trims were decent, most importantly it pulled like a freight train with no fuel cut, no bucking. Great right?!?!

Well on the way home the o2 sensor went to sleep. At idle it reads .00!! Rev the motor it picks up a little and settle back to .00. WTF is going on here? I check continuity between the plug connection and there good.

Car seems to run fine but I can't trust it not melting down.

Have you checked your caps in the ecu?

Alright, I'm an idiot..the .00 reading was caused by the base setting being set for 580 injectors!!! So that's why it was getting the so lean reading at idle. That would probably also be the reason it wasn't hitting fuel cut, due to adjusting (reducing air HZ)for 580's.

Funny thing is it loved that setting,pulled hard, no fuel cut, less than 3 counts of knock and .8 O2 at 14 psi of boost.

So I went back and re-evaluated my settings. Since I'm running a base pressure of 44psi, it should make the stock 450's act like 490's. So I set the base settings for 490's started tuning from there again. I'm having a bitch of a time getting the trims to the rich side and reducing the base setting to a lower injector size just gets me into fuel cut quicker.

So for those with more MAFT experience: At the dragstrip has anyone jacked the injector base setting up to stay out of fuel cut. I figure with some race gas in the tank, as long as it's not knocking it should be fine right?

If none of this make sence, I'm sorry, I've been messing with this thing all week and my brain is shot. I'm about to rip in all out and go back to the stock setup for tomorrow!

I know some of the guys have set the base setting "incorrectly" to get the desired results out of the tune. That's all that really matters.