Turbo Problems!!

HEY GUYS! i think i may know whats causing this to happen...confirm this for me...my first o2 sensor is directly after the turbo on the downpipe....well the open dump is on the manifold...before the o2 sensor...i believe that this is whats messing it up...like when the dump opens it thinks its going lean and dumps the fuel in..
 
The o2 sensor needs to be as close to the manifold as possible, I also have my o2 sensor on the DP but I don't have a cut out at all.
 
i mean can the dump be affecting it though? the o2 is like a inch from the turbo so i mean its close but i thought that maybe when the dump opened it was messing with the o2 readings, because the ecu is tuned for a internal wastegate, so no gas would be leaving before the o2 read it
 
i got stock turbo and im getting the same effects. i have a apexi tt and it tells me the afr in #.. usually when i hit boost it runs extremly rich and stubles, feels like im slowing down in boost. like 10.00 and it starts flashing lol. but sometime i run like 11s when in boost, and it pulls so nice!!! anyone know why?
 
HEY GUYS! i think i may know whats causing this to happen...confirm this for me...my first o2 sensor is directly after the turbo on the downpipe....well the open dump is on the manifold...before the o2 sensor...i believe that this is whats messing it up...like when the dump opens it thinks its going lean and dumps the fuel in..
This makes sense. Re-attach your dump tube to the downpipe and that should solve the problem... hopefully.
 
Its not the WG dump, something else has to be wrong with it.
If his wastegate is dumping exhaust before the O2 sensor then it's going to be reading more O2 in the exhaust than there really is and therefore cause the rich condition. Either way, the O2 sensor should be in the exhaust manifold ideally or at least before the dump.
 
ya i have the obx mani with a 38mm tial...

I believe that this is definitely the problem...because it pulls good until i hear that dump open then WHAM goes pig rich... it looks like the only good place to put the o2 bung would be on the 3rd cylinder toward the drivers side about 2 inches off the head...that way the dump opening shouldn't affect it...

But can it get a good enough reading off of just the one cylinder?
also i cant reattach the dump because it never was attached, its a custom divorced setup...plus i dont think that would fix the problem anyway
 
I'm running a primary o2 sensor on the DP and my wastegate dumps into the down pipe about 10" maybe more after the first o2.
 
I think it's the O2 location, more than the dump. Where is the O2? Can you post a pic? Custom is running a dump with a thunder mani.

This is the set up, to bad I didn't get a shot of it on his car.

turboinstalled017.jpg
 
see how the dump is kinda on a isolated runner though i think that the sensors still getting a good reading from the 2nd runner on that setup...

heres some pics..its seems as though i royally screwed up my 2nd o2 sensor last night though...but no cel has came on which is really weird...

I think a good spot to move the o2 would be on the 2nd big runner opposite the dump

PS ANYONE KIND ENOUGH TO DONATE A SPARE SECOND O2 SENSOR? POR FAVOR (I will definitely be moving it to the midpipe bung lol)
 

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If you can fit it put it as close to the collector as possible. Other wise you will only be getting a single cylinder reading.

I have my set up very similar to yours only have my secondary o2 way back on the mid pipe. You may be just having issues with the ECU running way lean from reading all that extra fuel with the secondary o2. It's designed to be further back after a cat so it's reading way to much fuel and trying to lean out. Could be your issue here, put it on the mid pipe and run a noin fouler also. That's how mine is set up.
 
^^^ Second O2 sensor does not contribute to the fuel trim of the car. It's there only to verify the catalytic converters are working properly.

Again, having an open dump tube before the primary O2 sensor will cause problems! Either move your primary O2 sensor to the exhaust manifold or other wise before the dump or have your wastegate dump reconnect with the exhaust somewhere down stream. By dumping the exhaust, the primary O2 sensor, in its current location, will read more oxygen between shifts and therefore tell the ECU to add more fuel.
 
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