Hi

my uk spec 300zx keeps cutting out when it reaches warm temperature after about 45 minutes of running. Then I have to leave it for it to cool down in order for it to restart. 
 

many ideas what the issue is? 
 

Thanks in advance 

Welcome to the Club!

Is that a clean (sudden) cut out or missing/stuttering beforehand? Any other symptoms ie fuel smell?

Welcome Wahid and look forward to updates on your UK 300zx.

Welcome to the club Wahid - and that fault sounds like the PTU.....

Common problem, owing to its proximity in the engine bay making it susceptible to heat over time. Assuming it is the PTU, your best cure is to buy a series 2 PTU (and wiring harness). The series 2 version is less vulnerable to failure ?

Richard

It seems to happen everytime it’s ran for over half hour and the engine is hot 

no smell of fuel or any other cutting off issues.
 

Richard has suggested that it could be the PTU. Anywhere know of where I can purchase one and is it simple to do by a normal mechanic? 
 

many thanks guys 

If you have an early PTU fitted (left in picture) then they are prone to failure from heat and vibration. The symptoms being missing

and/or complete failure after getting hot.  Nissan produced a replacement PTU (right in picture) which fixes the problem. It is also worth

upgrading anyway to the later PTU as a preventative measure. Also check the PTU connectors for corrosion and clean if needed.

a

The replacement kit is available from here (example supplier) and is plug and play replacement:

https://conceptzperformance.com/nissan-infiniti-nissan-oem-power-transistor-unit-ptu-series-2-kit-nissan-300zx-z32-22020-97e25_p_605.php

Edited December 10, 20214 yr by AndrewG

Amazing! Thank you for the information. I will purchase this and see if it fixes the problem. 
fingers crossed it’s sorts the problem. 
 

thank you once again 

 

This information on how to read the ECU fault codes and resolve common faults will also be useful to you:

http://www.twinturbo.net/nissan/300zx/forums/technical/view/1105629/The-Ultimate-Guide-to-ECU-Diagnostics.html

You can also use the Conzult diagnostic software running on a windows PC to display the ECU fault codes and real time

sensors and signals.

https://conzult.com/products.htm

a free Windows version is available to get started and covers most of the stuff needed (engine related)

https://conzult.com/downloads.htm