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Discussion Starter · #1 · (Edited)
Against my better judgement I let my brother and a close friend of the family convince me to complete my JBA header install before the summit.

I had them custom welded to Magnaflow high flow pre-cats and stainless flanges using a jig my brother and I made off the OEM headers. Beautiful weld job by Racing Greed in coquitlam!

The install went fine, we were careful with the O2 sensors, but now if I accelerate I get a P0420 and P0430 code thrown.

I clear it with my scanguage, and on the way here to Moab it threw the codes shortly after entering the freeway almost every time I stopped to get gas and started up again.

Now my first tank was my normal mileage. 350 km to a tank. The second and third tanks were slight improvements, and I am now getting 420 plus to a tank! I think my ECU readjusted or something... I also cleaned my MAF and air filter but this did not show in the first tank anyway.

I thought the Magnaflow pre-cats would be a good replacement for the OEM pre-cats, but am wondering what is going wrong. I don't think it is the O2 sensors (we were careful), but how can I check them? Is it possible the higher flow pre-cats allowed too much heat through to the O2 sensor?

The FJ is running better than ever, feels peppier, sounds amazing, but I don't want to clear codes several times a day. What should I do?
 

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HERE is another thread that JBA responded too...

Might not be a bad idea to give JBA a call and
explain your setup and see if they have a
solution...
 

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Discussion Starter · #5 ·
I just realized I left out a step during our rush to install them minutes before we left for Moab, disconnecting the battery cable.

This should have reset the ECU correct?

I wheeled my rig all day yesterday and did some hard pulls to see if it would throw the codes again and it did not. Could my ECU have relearned by now and the problem is now corrected? Any 1GR-FE ECU experts out there?

I'll post pics and such when I get home. They look killer and the performance was well worth it, even with the code problem.

Keep you posted.

Thanks guys
 

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Keep us posted as to the improvement in the MPG dept. That improvement sounds good. May have to talk headers also with ya when you get back.
Have fun down there.

:cheers:
 

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Discussion Starter · #9 ·
It is not unusual to get the cat inefficency codes after you have installed aftermarket high flow cats.

We can help you fix that problem. You can install this little black box from URD that will prevent those codes from being set and keep your light off.

Underdog Racing Development

Gadget

Again, you are the man!

I was just about to PM you as I figured you would have the solution. 5000km since the install and it still throws codes *sometimes.* Basically only if it feels like it and only if accelerating to freeway speeds. I wheeled it in Ouray and Moab and never got a single code thrown. Got on the freeway, nothing. Gassed up, re-entered the freeway and BLAM: codes! Sometimes I only get one or the other as well...

That's what I get for not following the directions! :rofl: But man does my FJ pull now!!! Sounds killer, and I am getting 50km more per tank routinely! I used to only get 350kms on the highway with my BFG mudds and all that extra armor weight. Drove straight for 26 plus hours to get home from Ouray and both the girlfriend and I got 400 or more per tank.

I will order the simulator on Friday when I get paid. Again, with the codes, I still have no regrets!

I need to post pics of my install... but I just got home from the summit. :boohoo:

Stand-by
 
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