I recently took the cats off my 99 Ranger 4.0L. Of course the CEL came on so I installed a CEL eliminator for a Mustang that has no cats but it did not work on the rear O2. What can I do to eliminate this problem but still leave the cats off the truck. Any help would great. Thanks!!

 

you did a mustang delete and then reset the light right? you know it might take a while to go off if you didnt unhook your battery for about an hour

 

you took the cats off!!! just get a high flow one its the same as not having any and your still legal and no cel lights

 

use the defouler trick. Search - don't be a n00b.

Oh - and this is a big waste of your time if you don't tune your truck more agressively to work with the reduced restriction in both heat and backpressure.

 

Waste of time and effort. Put the cats back on.

 

engines are designed to run better with the cats installed. put them back on.

 

good luck getting an inspection sticker

 

My rear o2s are turned off with my tune from Rogue. So you could get yourself a tuner and make sure to tell whoever writes your tunes to delete the rear o2s.

 

On Mitsubishi and Subaru roms, if you disable the rear o2 bit, it won't throw a cel, but it won't show readyness unless you force it. I don't know if his ford is the same way, but many oems are.

 

Let me fix this...


engines are tuned to run better with the cats installed. put them back on.

 

Thanks for everyones input on this. I have a chassis dyno in my shop and I am a SCT dealer but I really did not want to buy a handheld for this POS truck. BTW it did pick up 7whp & 5 ft lbs by removing the cats (without any tuning whatsoever). Changing exhaust around is pretty forgiving when it comes to tuning. However if you do anything to the intake side and it has a MAF on it then the tuning really becomes a necessary thing to do.

 

if its a pos then thats the point of even modding it?

 

removing cats is free... getting enough exhaust tubing to fill in the gap where cats used to be should not cost more than 10 bucks if ya look for scrap from a muffler shop. if he gained 7hp for 10 bucks. why wouldnt you do it?

and i dont care about the legal side to it...

 

First of all I mod everything I own. Heck I even modded my 2007 C-5500 tow truck. I didn't really mean that it's truly a POS. I do like my Rangers. I have owned 12 of these things and ALL have been modded from Nissan X-Terra blowers (thanks Thomas Knight) to big shots of nitrous, you name it I've done it.

 

Well.. in keeping with the "shade tree" mentality of cheap and easy power increases. Why not just put a piece of tape over the light?

I'm not positive on this.. but I do think that long term fuel trims will be effected if left alone.

IMO get a unlocked x-cal 2. That way you can get some real power gains with higher octane fuel and turn off the rear 02s. When you want to get rid of the truck you'll then have an x-cal 2 that can be sold or used elsewhere.

Rich

 

can someone shed light on which o2's do what?

The front ones are part of the decision making on the fuel mixture?

The rear ones do what? Verify emmissions, but still make fuel adjustments based on the data?

 

Good point wydopnthrt.

I don't believe the rear O2 makes fuel trim adjustments.

 

Rear o2s only monitor afr for catalyst efficiency (smaller amplitude switching signal @ steady state)