Maybe I'll swing by on Saturday I need to see Jon anyway.

I would like to meet you Baer! That would be sweet. I will be there around 3. Jon said that he's tuning a TTG37 that day before me.

The G will take a while to do,maybe I'll see you there.

Here are the codes that put me in limp mode: p0420 and p0430. I cant wait for my tune!

O2 sensors? Wouldn't think that would put the car into limp mode. But yeah, that tune can eliminate those inputs.

I didnt thik so either. But its both the primary and the secondary o2...so maybe thats what triggered it.

No, I don't think so.

question....this happened after putting on test pipes yes? What kind of gasket sits between your test pipes and headers? O-ring gasket, or regular flat gasket?

I have the Z1 metal gaskets. I used to have cnt hfc and they were leaking between the headers and cats. That leak also caused more leaks down the whole exhaust. But I got them all fixed. But yes, I did get the codes after install...which I thought that it might happen.

I have what sounds like the exact same power loss on a 2013 370z Touring AT. The problem only turns up during temperature extremes... either very cold <15F or very hot >95F. The issue is always resolved by shutting off the car and starting it back up. Sometimes it takes 2 or 3 restarts for the problem to go away. Symptoms include 1-2 second throttle delay as well as dramatic loss of horsepower. The most significant HP dropoff is in 3rd gear. When in full automatic mode (i.e. Drive), the car refuses to downshift on its own. I can floor the pedal and only sometimes will it aggressively downshift with extremely high revs... but the car hardly accelerates. No error codes are thrown at all... so the issue is impossible to reproduce or be fixed by the dealer. As it stands, I need to wait for the problem to re-occur again and then take it directly to the dealer without shutting it off. The problem does not resolve itself without shutting off the vehicle and restarting. Very dangerous problem because if it happens suddenly in the fast lane, it can be very difficult to get out of the way of the car behind you!

Baer, can you please elaborate on the Uprev problem you experienced? What was the explanation and fix?

I had an issue very similar to this and it turned out that it was the wire harness that connected to my driver's side throttle body was loose and had a bad connection. When I finally got the code to come up it was an easy fix. The hard part was the diagnosis. Good luck. Hope it's something simple

Update... I'm still having this damn problem. My car sounds like it's going to bog down and clunk out but has only shut off once like that. Other times the traction control light comes on and goes into limp mode. Of course this never happens when it's at r/t tuning which is who tuned me and they said unless it replicates while it's with them it's impossible for them to figure it out. I know it has something to do with the throttle bodies or tps but I can't have Nissan do a relearn because of my custom tune and when r/t tuning had me do a manual relearn it just seemed to make it worse. I'm getting really tired of this issue. Also now my wide band is staying at either 10 or 20 so I'm guessing my idle air control valve in conjunction with the tps or maf sensor location is the culprit but I'm stuck because r/t tuning is 4 hours away from me and they said only Nissan can do the relearn so I guess I would have to drive it up there have r/t remove the tune then tow it to the closest Nissan dealership up there so they can do the relearn procedure then tow it back to r/t for another tune.... Ahhhhhhhhh