i have a 90 5 speed 22re, was wondering on a good header choice for this truck. Also, is it OK to run this truck with no cat until i can afford to add it? does it affect engine performance? this truck has a downwind (after cat) o2 sensor, do all efi toyota trucks have that?

 

do i answer this and be a nice guy because the kid is new? or do i be a dick and just tell him to "search"

hmm... welcome to yotatech. a good header an LCE..... wait....why dont you have a cat on your truck?

 

A good header is indeed the LCE unit.

You CAN run without a cat, but the 22re has such small displacment that its really not going to net you any gain, you will probibly lose a little low end power. Plus you will be pulluting more.

You need an o2 sensor, every EFI truck has one (or two) but they need to be working correctly.

 

sorry guys, i did search the headers sorry to beat a dead horse. I know i need an o2 sensor, i meant do all toyota trucks have downwind o2 sensors. I dont have a cat now because when i bought the truck the exhaust had broken off at the manifold and there was nothing left. just wondered if i would lean it out by not running one until i can afford to get a proper exhaust done, also wondering if i could move my sensor up on the header.

 

yes, you can run without a cat for a little while.
But I wouldnt move the o2 sensor anywhere but the stock location.

 

How long ago did you buy the truck and did you buy it from a private party or used car lot ?

If the exhaust was broken off as you say, it's illegal to be sold in that condition.





Fred

 

after cat O2 sensor... hmm i was pretty sure they were right before the cat? I dont recall seeing any after...

and No don't move it anywhere else.. it was designed to get its readings where it is.. unless sumones already moved it to its location after the cat

 

On two O2 sensor vehicles, one is right in the exhaust manifold and one is right after the cat.
What good would it do to have it before the cat ?




Fred

 

I don't know the differences in terms of what the 02 sensors read, but mine wideband is pre-cat.. Measures fine.

Dyno shops can run them post-cat to get A/F for dyno runs, so either position must work.. I don't know what they measure that is different.

 

Out of curiosity, what benefit would one gain from having a second o2 sensor pre-cat? I ask because I've had to replace my exhaust from the manifold back because the front pipe was leaking, there was no cat, and the muffler was a rusty piece of junk. The old pipe had no pre-cat sensor, and operates only on the sensor in the exhaust manifold. The new pipe I've got has a pre-cat sensor bung, however I've got no sensor, and no idea what I would need to do to wire it in, so I was just going to bolt on a blocking plate in place of the sensor.

I figured since the truck was running fine now with just the one sensor, I might as well save the $60 and the time of wiring in a second sensor pre-cat. Would I notice any difference with a second sensor, or should I just leave it the way it is?

 

The post cat sensor is to determine if the cat is in fact working.






Fred

 

pre cat o2 sensor reads air to fuel ratio and is critical. if you only have one that's what it does. if you have 2 the second placed after the cat is tipicaly for newer vehicles and reads your emisions. you only need the one to run and that's the air fuel. as far as a 02 sensor in the manifold that's the egr not 02 it may be right after but I've never heard or seen one in the manifold itself.

 

I have no pre cat o2 sensor, nothing in the manifold, nothing in the pipe as far as i can tell, the pipe itself was gone but there were no plugs or wires hanging anywhere that i can see, is that normal?

 

do you guys know what wires go were on a bosch 02.

 

if you have two o2's it's most likely a California model