RomRaider

Hi guys, I'm 67 years old, rebuilt my first mgb engine at 16, done jags, z's, and na forester since then. I entered the turbo world rebuilding, and then manual swapping my 06 obxt. After finding a similar model tune on romraider and flashing it onto my ecu, the car actually runs pretty well. However, after using the romraider maf scaling tool numerous times, even when my compensation is less than 5%, I cannot get my afr's to stay at 14.7. They always go rich, around 13.8 to 14.1. I know the tune was not made for my car, especially since I've decatted the up and down pipe, have 3" exhaust and cold air intake, but I can't even get the idle afr right. I have a boost gauge and wideband and have logged some data but can anyone tell me what to look for? or what table could be preventing me from attaining 14.7? Thanks for your help. Please be nice, I could be most of you all's grandad.

joe.

are you able to post the rom, a log showing what's happening and the result of hitting the LTV Info button in romraider saved as an image? This info should be enough to try and offer some useful advice.

Thanks a ton. I hope this is what you needed.

joe

OK so you can see straightaway your IAM has dropped. This value should be 1.000 after a small amount of driving - the starting value in your tune is 0.500 and from your LTV info the ECU has dropped this to 0.375 in a response to heavy detonation. You've only logged fine learning knock - you should really be logging feedback knock as well to get a better idea what's going on.

Personally i'd say some areas of your map have a bit too much timing in there especially in the 1.0 g/rev area but looking at your LTV info it seems the worse of it is concentrated in the low RPM area and below 0.8 g/rev. As a starting point you could try pulling 8 degrees off your entire base timing table and see what that does for you but its also possible something is rattling about in the engine bay (and the ECU picks it up as knock) or possibly the thing rattling is one of the pistons...

For your fuelling - you've not logged final fuel base or MAF volts, which you'd want to be using to get your MAF scale correct. But your not really ready for MAF tuning yet as you need to clear up a LOT of that knock correction so that your IAM climbs up. Once you go to an IAM 0.3500 your ECU will switch to the primary open loop fuelling FAILSAFE map. Normally this map is richer than the main primary open loop fuelling table as a means of protection for the engine when something goes a little wrong. However in your case it will actually lean the car out a little as your failsafe map is asking for less fuel than your main fuel map. As it stands if your wideband is reading correctly then your far far too rich - but once you start logging the right parameters and get the MAF scale dialled in better then it should start to clear up.

Then lastly your boost - your asking for 0.85bar but your only making 0.6bar - once you get the timing and fuel sorted then you can revisit this. Could be a boost leak, could be just tuning, could be not all 4 cylinders are providing exhaust gasses to spin the turbo.

Thanks man. Learning knock control is like being back in freshman calculus. I'll log the right parameters and adjust the timing table. I rebuilt the top half of my engine along with rings, but didn't do pistons or short block. I have all the parts thinking "someday." We'll see after I do these things first. Really appreciate your analysis.