This question may have been asked before, but i havent been able to find an answer so here goes... I have an HC3S luce which originally had a series 4 (1986ish)13B turbo in it with auto trans from factory. I bought it with no motor or gearbox, and bought an import series 5 (turbo II to you northern hemispherians) engine and manual trans and fitted. It has the Series 4 AFM and standard exhaust. Now, the engine will run, idles fine, drives ok, but it cuts out when it comes onto boost. My question is will the series 4 ecu run the series 5 motor sufficiently or do i have to wire in a series 5 ecu? I havent tested boost pressure or anything yet, i thought id see what you guys thought first. Its kind of like the ECU thinks the mixture is too lean and kills the motor till you take your foot off the gas pedal. Any help much appreciated

 

As long as you took all the electronics for the S4 style engine and put it on the S5, then you should be good to go. So if the car ran before on the S4 style engine it should run fine using the S5 block as a replacement for the S4 style block.

If the Luce EFI system is anything like the S4 (probably is almost exactly the same) then check the boost/pressure sensor and TPS.

 

Thanks for the help!!! The entire engine is series 5-block, inlet and exhaust manifolds/turbo etc. but i shall check the TPS and boost sensor. Sounds like i may have to try locate some series 4 bits otherwise.