NSX won't start after header install

[M. Scott]

This weekend I replaced the stock headers with a set from Taitec. Since wrapping up the install the car will turn over but not start. I have read countless threads regarding no start conditions and am at a loss. I will list the steps I have taken thus far:

Spliced in Bosch O2 sensors
Jumped fuel resistor
Replaced main relay (bought 2, tried both)
Replaced Bosch O2 with Denso brand. (Not spliced, plugged into engine harness but not installed into headers. I thought my original splice job was the cause of the failure.)
Checked ignition switch and cleaned. (Lights on cluster work when switch turned to position II)
Pulled ignition coil and plug verified plug is sparking.
Checked fuses.

With the Bosch spliced in I pulled codes 41 and 42. With the Densos it only threw a 42. I swapped the front and rear O2 and the code followed to the other bank (threw 41). I checked to make sure all connectors and grounds were attached in the engine bay. I didn't disconnect anything other than the O2 as required to complete the header replacement.

I would be grateful for any information on my next step or perhaps something I have missed.

- - - Updated - - -

I pulled the banjo fitting for the line coming off the fuel filter to the rail. Tried to crank and no fuel passed through the system. Not sure if this will help to narrow down the problem.

 

[Aluminsx]

Just a shot in the dark but could it be a bad ground? Lots of stuff gets moved around when you fiddle with the exhaust so it could be that simple.

 

[M. Scott]

In my research for this issue I noticed a trend that in most cases the OP fails to return to the thread and discuss their solution. After several days of troubleshooting and replacing parts my problem has been resolved. I have a background in aviation maintenance and as such I feel it is important to share the information. In my case accept some humility while doing so.

As I stated in my original post I determined I was not getting fuel. Since I was doing the 60k service I replaced the fuel filter and ruled that out as a possible cause. During this endeavor I also replaced the main relay, fuel pump relay, and pressure regulator. I was at a loss and started tossing around the idea of swapping the NSX for a 911. After some soul searching I decided to carry on and put 12v to the fuel pump, got nothing. I had at this point called the dealership and ordered a new fuel pump accepting my fate.

I began to research dropping the fuel tank and replacing the pump. It was during this time that I learned of the fuse box in the driver's foot well. I am out of the country most of the year and maybe get to drive the NSX for 2-3 weeks a year. I never knew that such a fuse box existed. I discovered the 15A fuse labeled "Fuel Pump" was indeed blown. Replaced it with a spare and the car started immediately. I must have incorrectly applied the 12v to the pump. Had I done it correctly I would have known the pump was not the issue. In the end I felt like a big idiot but can rest assured that a very thorough 60k service was done, considering all the new fuel components. I definately learned a bit about the car and am glad I dealt with all this one my own. In aviation we have the acronym K.I.S.S. which means Keep It Simple...Stupid. I will keep that in mind from now on.

 

[Nefarious]

Everyone has done it. I'm glad you figured it out and didn't make the switch to a P car.

 

[brettowen]

You're absolutely correct! There certainly is a trend where the OP fails to share their solution. Thanks so much for completing the loop! Hopefully, this too will be a trend!