B13 Turbo install O2 Sensor

[AnthonyB13]

I have a question reference O2 sensor placement when adding a turbo to a SR motor. The car that I picked up had an O2 sensor bung on the down pipe (turned out it is a 12mm thread post cat sensor from a 200SX) and of course the GTIR jpipe has a bung in it as well. Since the B13's only are wired for a single one and I am not running a secondary wide band monitor where would be the best placement for a sensor and should I use the normal B13 one? I am going to end up getting a new down pipe anyway since the current one is a bit messed up, so should I get one with an O2 bung in it or use the one in the Jpipe?

[ErixSEL]

j-pipe is to close, the sensor is suppose to be 36 inches away from the turbo on a turbo car and like 12 for the head on a N/A car i believe

[AnthonyB13]

Well that answers the question, I appreciate it bro.

[ErixSEL]

yup NP

[Jason@JGY]

you mean an aftermarket o2?

if so, we put them under the firewall right behind the motor
that is where mine is on the blue dragon
you need to run the factory one in the J pipe

[AnthonyB13]

Factory O2 sensor is the one that I am talking about. I was mainly curious as the down pipe on the car I picked up had an O2 bung on the down pipe but the guy was only running an AFR gauge, not a wideband. He "misplaced" the jpipe he originally had on the car so I could not tell if he had it plugged or not. But either way I will be calling you later on Jason to get a down pipe among other things.

[Jason@JGY]

cool
just don't forget, that I'm not on the phone much, it's better I'm doing other stuff for all our sake :-), we have several installs that are needed to be done

[AnthonyB13]

No worries, every time I call I get the info I am looking for and quick service so whever I talk to it works out in the end.

[AnthonyB13]

Ok new problem has cropped up. I can start the car, but only by giving it gas, if I let off it chokes and dies. When I give it a good amount of gas everything seems to run ok other than a miss here and there which I believe to be tied to the problem I am having while starting. Also the AFR is all over the place bouncing back and forth from lean to rich while I try to keep the engine running. The tach is still acting crazy though it does settle down and start to read once in a while, but I think that is mainly just a wiring issue after talking to you guys on the phone. And just to clarify I am trying all this without a down pipe until I can order another one. Any ideas?

[Jason@JGY]

huh?

while playing with the gas, the AFR will be all over the place........so that's cool

what ECU tune do you have?

[AnthonyB13]

Ok the ECU is JWT flashed for the current setup I am running, T25, 370cc injectors Walbro fuel pump etc.

Her is a total breakdown of the current problem, while cranking the car the only way to get it to start is to apply throttle, otherwise it will turn over and then the RPM's immediately drop and the car dies. Once the engine is running if the throttle is released to go back to idle the engine sputters and dies. I understand the AFR will move around while applying and releasing throttle but it jumps erratically and drastically from one end of the spectrum to the other. I really need to get these issues addressed as while I am currently on leave, once I return to work this car has to be up and running for me to get to and from my office.
I have done a ton of research and if I understand the various threads it could be IACV, TPS, CTS or any combination of the three, or none of them. I was curious to see if you guys had ever come across anything like this before and if you had a solution. That way I get it solved right the first time instead of spending a ton of cash on parts that I don't need right now.

As for the tach problem, it does not read then it springs to life bouncing all over the gauge even pegging itself when the RPM's are no more that 1500 to 2000. Once in a while it will start to read normally, but only for a short time then it begins acting erratic again. I talked to you guys on the phone about this and at best guess it is a bad wire somewhere between the tach and the ECU. This is totally secondary as I can shift by ear easy enough and plan on installing an after market tach in the long run anyway.

[AnthonyB13]

After reading the BoV thread, I do have a Greddy Type S in there, would that be causing the idle issue? If it could be the culprit is there a way to find out if it is?

[NathanM]

It's a possibility, can you get the car to idle at all?

[AnthonyB13]

I wasn't able to get the car to idle, but today I solved the problem. I did a ton of searches in the past couple days on the problem on various forums, and no one really addressed the total issue. I did get a few ideas and went on a hunt to figure it out. First thing I tried was I disconnected the TPS and started the car and it immediately ran a ton better. I shut her off reconnected the TPS and started her again and it appears as though that did the trick so that has pretty much solved the idle problem. To be honest it suprised me, as my normal luck would have me chasing ghosts for days before I figured it out. Right now though I am at a sticking point as I await funds to get some more parts to see if I can get her to the point where she is ready for the road. I appreciate all the help guys, it really came in handy trying to get answers to my questions.

For the moment my next project is the hood I picked up from the junk yard to replace the rusted out one with the WRX scoop. I have a very small scoop that I am going to mount off to the side of the hood, directly over the air filter. Aesthetically it will be good in my opinion, smoothed into the hood and of course painted to match when I get the hood redone. I will post up pictures as it progresses.

[NathanM]

Do post pictures it sounds interesting. My initial reaction is that it will look kinda funny but hey if you can pull it off. I'd also be a little worried of rain with it positioned right over the intake.

[AnthonyB13]

I thought about that and I am working a way to alleviate any problems, though I don't have a hard solution as of yet. I may just end up placing a rubber flap in there the way the WRX scoop has it with a water channel leading away from the filter, but I don't know as of yet. I know it will look a little strange at first to most people, but hey if it was about pleasing the rest of the world all of our cars would look the same lol. The scoop itself is relatively small, only about an inch to an inch and a half tall and only about 6 inches wide.

[Jason@JGY]

I'm not a fan of hood scoops and vents. It makes stuff get wet and rust. Cooling the air before it goes into the turbo doesn't do that much either.

[AnthonyB13]

Well right now I still doing design, haven't really finalized anything as of yet. My main goal with the scoop was a little bit of aesthetics and increased airflow into the engine bay. But like I said, all ideas at the moment.

[jholman]

So your TPS was acting weird?