SteveSprint

Mickey Thanks for the welcome. On further investigation it appears the 14CU and 14CUX main connection pin layouts are the same except for the serial port ground, see pages 101 and 102 http://www.remap-14cux.uk/14cux-docs/1314CU_14CUX_Systems.pdf . The 14CU had a separate serial ground wire on pin 37 that was later combined on the 14CUX’s ground on pin 27, therefore you would have to ground pin 37 in the 14CUX loom. The 14CUX serial port ground is highlighted in this diagram http://www.remap-14cux.uk/14cux-docs/14CUX_diagram_1993.pdf . If RoverGauge did successfully connect to a 14CU it wouldn’t show the fuel table correctly as RoverGauge is designed for the 14CUX prom layout with the 5 fuel maps, where as the 14CU only has one fuel map. However I still live in hope 14CU serial port would connect to RoverGauge and read/save the prom chip but there is no guarantee it would work. The only other way to read the prom chip would be to cut out the chip and solder the legs back on. I’m personally interested to see a 14CU prom file especially to see if the 14CUX map 0 (limp home map) has the data structure as the 14CU’s single map, sorry I don’t get out enough in the winter. I’ve also just noticed the 14CU & 14CUX injectors are mechanically different but electrically and the flow rates are very similar, see page 68 http://www.remap-14cux.uk/14cux-docs/LR_Fuel_InjectionSystems.pdf You are always welcome to help yourself to the tune chip files here http://www.remap-14cux.uk/bins/ where you’ll see I have three 4.2 tune files to choose from, however as you’re running a non cat map (3) without cats I suggest R3116 as it the only 4.2 chip file that actually has the 4.2 fuel table in the non cat maps 1,2 & 3, where as R3361 & R3834 non cat maps contain 3.9 fuel table and data. To quickly identify the fuel tables in each map see the “Map” and “Main Fuel Scalars” rows in this table http://remap-14cux.uk/LR-TVR-settings.html . I would be happy to add any additional maps if you have any. I’m sure you realise the main advantage running the non cat maps is you can remap for the following AFRs 15.5:1 Motorway cruise 13.5:1 Smooth idle 12.7:1 full load/max power Fridge Sorry I don’t have any GEMS ignition maps, I’m sure you know GEMS has knock sensors and the fuel and ignition is self mapping, however here's a good guide for TVR ignition timing https://www.pistonheads.com/gassing/topic.asp?t=828064 Cheers SteveSprint

mickeyw I’ve just spotted this thread and if you are still interested I can confirm your PRC6999 ECU dated 0189 in the picture is a 14CU and not a 14CUX, it doesn’t have the 14CUX’s MVA5033(KA) square chip and therefore the tune chips are not compatible. 14CUXs manufactured in the first year of production have the MVA5033 chip and all later 14CUXs have the MVA5033KA chip. The MVA5033(KA) chip contains extra “Random Access Memory” and the interface to the OBD fault code display plus some extra functions that go over my head. From a Land Rover Manual 13CU (1987-88) 14CU (1989) 14CUX (1990-95) Have you tried connecting RoverGauge? The 14CU use the same pins 9 and 18 for the serial port but I doubt all the diagnostics would display correctly as the 14CU doesn’t have 5 maps like the 14CUX. I live in hope RoverGauge connects just to download a copy of the tune map as I’m very interested to investigate the differences between the 14CU and 14CUX in more detail. Cheers SteveSprint