Ecu/ loom question.

1. Jack_Norris Regular Poster Joined: Feb 2012 Canvey Island Posts: 383 2 16'v Saxo vtr's

   #1 10th August 2018, 14:05

   Ecu/ loom question.
   
   If you didn’t know I did my vts swap last year it’s a 2000 3 plug VTR and I fitted a 2003 3 plug vts lump. For whatever reason it would not fire on the vts ecu, sent it off to be unlocked and tried a different ecu and still nothing. However is runs perfectly on the original VTR ecu and I’ve since done 14k miles on the VTR ecu running the 16v engine. Only thing I’ve noticed is it’s only revs to 6.2K so presume that’s down to the VTR ecu.
   
   I’m looking to fit cams so would need to be remapped but I’m unsure you could plug the vts ecu in, get it mapped and be all good. Or mapping the VTR ecu to run the cammed 16v engine.
   
   Alternatively I have a complete spare engine with a single plug loom and ecu so I could convert the engine over to a single plug and go from there.
   
   Any ideas on why the vts ecu wouldn’t work can only presume it’s something in the loom as the car has run for over a year on the vtr ecu.
2. Chipwizards Frequent Poster Joined: Nov 2009 Posts: 576

   #2 10th August 2018, 22:02

   You can't use a VTS (Magneti-Marelli) ECU on a loom for a VTR (Bosch) ECU because the pinouts are very different.
   
   You'll be lucky if you haven't damaged it.
   
   Likewise, you really really shouldn't run the 16v engine on the 8v ECU for several reasons, the fueling will be rich at low and mid-range speeds where the 8v has better volumetric efficiency, and then it will be lean, very lean, at high revs where the VE of the 16v is better and you won't be getting the full range of performance because the rev limit of the VTR ECU is lower.
3. Jack_Norris Regular Poster Joined: Feb 2012 Canvey Island Posts: 383 2 16'v Saxo vtr's

   #3 10th August 2018, 22:37

   Quote:

   Originally Posted by Chipwizards You can't use a VTS (Magneti-Marelli) ECU on a loom for a VTR (Bosch) ECU because the pinouts are very different. You'll be lucky if you haven't damaged it. Likewise, you really really shouldn't run the 16v engine on the 8v ECU for several reasons, the fueling will be rich at low and mid-range speeds where the 8v has better volumetric efficiency, and then it will be lean, very lean, at high revs where the VE of the 16v is better and you won't be getting the full range of performance because the rev limit of the VTR ECU is lower.

   Thanks for the reply its was a full swap so a vts loom had to change a few pin locations to get the gauges to work but its a vts engine and loom but a vtr ecu and interior loom. was getting fuel and a spark would fire once and die. But on the vtr ecu fired up straight away and runs perfectly fine.
   
   Knew the vtr ecu would have some downsides but i've ran it like this for over a year now get good mpg