Extended Crank on 1994 Nissan 300ZX

I have a 1994 300zx non-turbo. Over the last 6 weeks, the vehicle has had an extended crank, when the engine is cold. I have tried some basic repair myself, but have been unsuccessful thus far.
I have changed the
fuel filter, spark plugs, battery, and the fuel pressure regulator. I recently read the codes that the ECU has and it 32 and 34, which is a knock sensor or a EGR valve/solenoid.

Any ideas or thoughts would be greatly appreciated.

Asked by for the 1994 Nissan 300ZX
i had a similar problem on my 1990 300zx, i had just replced the cambelt ,tensioner, idlers and water pump, i reassembled it and it took a long while to start from cold, it never had this problem previously. i discovered the temp sender connection near the themostat housing was loose, after carefully fixing the problem it started immediatly and has done so ever since.
2 answers
These problems are very hard to fix, I've even seen it caused from the type of fuel used. Did you find out what was causing it in your vehicle?