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Hennie · Sun Jun 10, 2012 12:34 pm

PR wrote:Well, now that you're back to stock, it's done - but for other modifiers, when you remove the cat, the straight pipe you replace it with should have a place to screw in the O2 sensor. It's just a hole with a thread, and the sensor screws into it. That way you have no cat but the ECU is happy and no engine light.

Done that but it still did not work, the engine light stayed on, even took it to Jeep who tried to calibrate the sensors but to no use.

PR wrote:However, I agree with Hennie, and most modern engines get no or very little benefit from air intake and exhaust mods, because they are already designed for ultra-efficiency. Gone are the days you could pull off the air filter and muffler and pick up 10-15HP. Nowadays it's normally not worth it.

True, learned the lesson the hard way. The exhaust cost me about 12000 AED thus far, luckily it is sourted now. Could have bought a new Fj for that price, LOL

PR · Sun Jun 10, 2012 3:08 pm

Do you know if it's only one sensor, Hennie?

If that's the case then that would mean the new oxygen flow is beyond what the sensor can measure - wow - which means the stock cat must be super-effcient (or super-restrictive). Interesting.

Oh, wait, is it one sensor before the cat and another after the cat? In that case, it would be comparing the difference between them, and that's why nobody could get the light off.

I guess all we have to do is search the US Jeep forums and those guys will have debated and analyzed every angle of what I'm trying to guess now!! LOOOL

Wasif Ahmed · Sun Jun 10, 2012 3:30 pm

There are two sensors one before the cat and one after...... what you needed was an O2 stimulator in place ....but its too late now anyway

For 1.2K you probably will get a half day ride in an FJ ....LOOOL

Richard Moss · Sun Jun 10, 2012 9:28 pm

One advantage of having older Jeeps is that both of mine were supplied without emissions kit - no cats, no O2 sensors!

Wasif Ahmed · Mon Jun 11, 2012 11:07 am

Richard Moss wrote:One advantage of having older Jeeps is that both of mine were supplied without emissions kit - no cats, no O2 sensors!

How does it pass the emission test every year ?

PR · Mon Jun 11, 2012 11:40 am

Did you ever hear of anyone failing because of emissions? I haven't LOL I think the emissions tolerance parameters on the testing machines are set really high.

I've had several older trucks without cats and they go through no worries.

For excessive noise they do fail, though; I once tried to pass my Jeeper Eater with straight pipes ('83 GMC truck, V8 engine with headers, no muffler, lifted 6 inches LOL) but they wouldn't pass it even when I tried explaining it was for the desert only, etc. Had to go weld on a muffler and come back, and then cut if off again LOL That V8 sounded so sweet guys 8) I would start it in the morning and just sit there and smile while it gurgled... BTW, I do drive with complete respect for traffic rules on road so the missing muffler never bothered anyone... but in the desert it sounded GREAT!!!! 8)

Hennie · Mon Jun 11, 2012 11:59 am

They never failed it for emissions, they did however fail it for noise, when I asked them how they measure it he just pointed to his ear, LOL. Had to weld in a muffler and then afterwards took it out again.

Wasif Ahmed · Mon Jun 11, 2012 12:54 pm

Some guys in Dubai who had headers installed on thier FJ which required removal of the first set of cats have failed the emission test recently

PR · Mon Jun 11, 2012 3:30 pm

Could be they are gradually increasing requirements, as probably their plan is.

I've been in line at the testing center, worrying about my car passing, and this farm pick-up, belching black smoke, wheels a-wobbling, and all leaning to one side next to me passed with flying colours!!! LOOOL

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