Builds DIY FJZ80 Low Budget Turbo Build

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With that negative fuel trim I would get the 4" MAF tube. That will get the LTFT back in the positive and push the WOT rich further out in the RPM band.

But it might also have you in closed loop during boost which means running an AFR of 14.7. So run an O2 manipulator to trick the ECU into running an AFR of 12.3 or more during closed loop.

3.5" MAF was the biggest treadstone had. I took a few tenths out of every cell below 0psi in the fueling map in the URD software and that put long term trims at around 4-6 and short term between -2 to -4. So far so good and no "too lean CEL" anymore.

The AEM F/IC units alter the injector pulse directly while the URD unit only manipulates the MAF signal, which isn't ideal.
 
3.5" MAF was the biggest treadstone had. I took a few tenths out of every cell below 0psi in the fueling map in the URD software and that put long term trims at around 4-6 and short term between -2 to -4. So far so good and no "too lean CEL" anymore.

The AEM F/IC units alter the injector pulse directly while the URD unit only manipulates the MAF signal, which isn't ideal.

for some reason I thought there was a link for a bigger one.

The CEL is an internal error warning you that the fuel trim exceeded 20%. The engine isn't necessarily running lean. If there is another LC that you can get the FT% from that is stock I would try and get your system to mimic it. That way if you do get the error it is likely something that needs investigating.
 
From the u-tune guide as long as both trims cancel each other out that is as close to stock as you can be. So if the long term is -5 and the short term is +5 that means it's pretty much dead on.
 
From the u-tune guide as long as both trims cancel each other out that is as close to stock as you can be. So if the long term is -5 and the short term is +5 that means it's pretty much dead on.

not really.

That would be ideal for your location at that time but not necessarily acceptable all the time.

The environment plays a big role in what the fuel trims read at any give time.

Altitude, temperature, humidity, barometric pressure and I'm sure other variables influence those readings.

As an example since I live at sea level and in New England I'm almost always at a +12% LTFT. Now if I was to drive to a high altitude in the dead of summer I might be at -12% LTFT. The thinner hotter air would be compensated for by subtracting fuel.

So that is a 24% swing in FTs and if I dialed my truck to run a 0% fuel trim in Boston and then drove to that high elevation the FT would be -24% and the CEL would trigger with a P0170, system rich.

That's the reason I'm suggesting for you to match another stock truck's FTs. This way you stand a better chance of avoiding a CEL due to the FTs being out.
 
Aem f/ic 8 install



ForumRunner_20130501_005302.webp

ForumRunner_20130501_005302.webp
 
Ayyyyy Carramba....
 
Up and running and awesome.

AFR linked in
AIT input
Built in boost controller
Built in injector drivers
Full datalogging ability



ForumRunner_20130501_101837.webp

ForumRunner_20130501_101837.webp
 
It's never enough with tuners. LOL. Exactly how I am, start with a small idea, the next thing you know you have built the Pyramids. Great work. But, is this still a low budget turbo build???
 
Well, it's done right, in many ways, with the cheapest parts that I could find.

If you look at the price list there is a lot of stuff on there that is high quality and relatively cheap - as long as you hunt down the deals.
 
So far so good. It's a really nice unit. It took me hours to figure out how to wire the cam and crank sensor wires since the AEM instructions were wrong and useless.
 
That was the port for the valve cover vent hose. If you go turbo you move that port to the pre turbo pipe or with a catch can setup.

So you either have to cap it off or put a plug in it post turbo.

Almost perfect 3/8 size too. Just run a tap through and it's good to go.
 

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