Grunnen

A friend of mine has a Dodge Rumble Bee and when he installed a Magnaflow high flow cat his Check Engine light came one. Has been like that ever since. Anyone had that issue with a 2nd gen 4Runner?

Will it throw a code if I run a straight pipe?

yoder519

i got a 95 pickup with a magnaflow hiflow cat and it didnt throw a code or make any lights come on. youll be fine. buddy of mine gutted his cat on his yota and it made the check engine come on, but if you jsut take the cat off and put in a piece of pipe it shudnt

vital22re

iTrader: (2)

how is gutting a cat(removing the components) different from a straight pipe? I've got a magna flow on mine as well and i've got no codes. As far as the dodge goes, do you know what the code was for? could be anything from transmission to coolant temp sensors throwing codes.

abecedarian

without knowing what the code was on the dodge, discussing it is a moot point. The Dodge is OBD-II and you are barely OBD-I.

On the other hand... I don't think you'd have an issue with a Magnaflow converter even if you were installing on a California model with the sub-O2 sensor.

tc

Straight pipe or gutted cat will throw a CEL GUARANTEED.

Aside from which it's a federal offense, and is just as likely to LOSE you power/torque as it is to gain you any.

Dirt Driver

That's what I was thinking too.

If my truck was passing the sniffer, I would just ditch the rear O2 sensor and use a simulator or get a 49-state ECU.

Hayes

Besides the fact that it is illegal and that it gives our hobby a bad name.

Gutted cat would pass inspection (visual), but it will lose you power. You need restriction in order to make power. There is no point to this modification and please don't give the tree huggers anymore reason to close our trails.

Jay351

Unless you got motor, straight pipes will lose power.

Throw a hi-flow cat in there. Your engine won't throw a code, its not that sensitive.
A cat will keep the exhaust hotter thus its velocity faster. Cold pipes = slow exhaust flow= engine working harder to expell exhaust.

You can get things for newer cars that will modify the o2 sensor output and make the engine happy. I can't remember what the hell they are called though, im not that current...

Grunnen

I dont know what the code was for but when I mentioned wanting to put a high flow cat on mine he told me what happened to him. Its an 08 and the only thing thats been done to it was the complete magnaflow exhaust so I doubt it was anything else.

Dont care about restrictions or hippies I live in florida and no 1 would know except me (no inspection). But if it is less efficient to have a straight pipe then I will go ahead and get a high flow.

What is this simulator you speak of? Any threads/info?

Thanks for the input everyone.

paynemw

aight I just did the same thing... you probably had a highly efficient cat which makes the truck legal on the left coast... cough cali so when you ditch the oem cat and put on one high flow cat like i did from magnaflow or your aftermarket dealers the reading for the below threshold O2 sensor will be off because your cat is not taking out all the emissions like the original one did.... so your engine is working right but because the readings the O2 sensor is sending to the ECM are outside of the original range the check engine light is going to come one... you need to get the check engine light to go off because right now your computer thinks theres something wrong and to compensate is burning more fuel and yeilding a worse gas mileage. You can buy a O2 simulator from URD like I did or you can return spend a metric buttload of money and put your gay california spec cats back on the truck..... i chose the O2 simulator... but apparently its illegal in some states

Dirt Driver

It is a little electronic thing that mimics a properly operating O2 sensor.

http://www.mkiv.com/techarticles/oxy...sor_simulator/

I also found this:

http://www.s10forum.com/forum/f89/do...ulator-126774/

That's with Chevies, though; I don't know how the $6 method works with a Toyota. EDIT: I forgot that our trucks usually have bolt-in senors. Doh.

Hayes

Did someone edit out his ignorant "I don't care about anyone but me" comment?

Grunnen

seems they only work for OBD-II vehicles

nope you just didnt my post entirely.

my statement stands: i dont care about hippies or regulations. there are worse things happening in our world than a running no cat.

Hayes

I read your post word for word. I stand behind my statement. Someone sits in their office all day perusing the internet for threads just like this, then they twist it and use your statements against us.

Grunnen

Well I'm not going to run a straight pipe. Not because of the hippies, but none the less, everybody wins.

iamsuperbleeder

not true

no cat on my 22re, no CEL, and the torque gain was noticeable


I'm not going to argue with it being a federal offence though I'm not saying it's right that I did it... at the same rate, I've also removed the air injection and EGR system, lol

mattaway

it might be illegal, but my check engine light didn't come on, and i got a noticable power gain from gutting my cat....

Kiely

There are O2 “spacers” or “anti-foulers” that can be installed to slightly remove your O2 sensor from the exhaust stream. This is a fairly common mod on Acura RSXs (my other hobby) that have exhaust system mods (racing pipes or high-flow cats). I haven’t had to use one, my high-flow cat on my RSX didn’t turn my CEL on but from what I understand they work. But most cars with this mod have also had their fuel mapping “hardwired” so it is a bit of an apples and oranges comparison between a 2002+ RSX and a 1990s Toyota truck.

You can do a Google search for “O2 sensor spacers” and read all about them.

billkmiami

My V8 Mustang has no cats- (removed) - installed headers, slightly larger pipes with 3 chamber Flowmaster mufflers(dual) and attached dumps at the exit side of each muffler- (no pipes coming out of the back)- the power gain was very noticible - car has o2 sensors before the cats so once removed the computer did not know the difference!- less restrictions=more power- so I assume the same will happen on my Toyotas using the URD simulator with the Cats removed and a free flowing muffler installed! This also stops the dumb ass theives from ripping off hard working people who have to pay for their honesty. (Cat theft) So I say screw the Cats and let the exhaust flow!

ozziesironmanoffroad

ha, billk, ur avatar. ive done that in one of those things... in fact i did it 3 times before getting the hang of it... those things are indestructible!!!!
id say leave the cat on, whats it hurting? i like breathing AIR, not smog. im no hippie, but why would you want to contribute more than u have to to pollution?