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I need to lean out the cold start idle A/F. being rather new, I'm not seeing a cold enrichment table, but the car is commanding .6 Lambda on start up, and I believe that is causing my cold start surge.
once it gets to .8 or leaner, it calms down and idles perfectly..
Thanks
the open loop (gas/gear) tables control the commanded until the trims take over
Hmm... All of mine stock and in my full tune, every cell is 10.00
i think they are 10.00 and the "IVT gains gas" is the decimal so the 10 multiply by IVT should be your OL commanded ? they were a bit different the e40
Following this thread, same issue here though with an E38. EQ is pig rich over commanded up until about 200F IVT where it falls back in line, which is about 2 minutes of idling from a 35F cold start. Drastic changes to the IVT chart do not seem to have an effect at all. I would think that any richness hanging over from the startup would have more than cleared out by then.
My injector tip temp chart doesn't even start until 176F, and stock it is all 1's anyways. Not sure where else to make changes.
5ft24, what does your IVT multiplier chart look like?
My stock open loop tables go as high as 3.??, and my IVT table is a low of 1.0, and going up to 1.387 at colder temps/higher loads. I was making drastic changes to lowering my IVT chart to even get the actual down to commanded (it was waay richer), then realized I was hitting a wall in the EQ Ratio Min chart, under Fuel/Open Loop-Base/Misc. I had to fudge that to allow more fudging of the IVT chart, to the point that it is commanding above 1.0 in the low IVT temps just to get it down to, say, 0.8 lambda actual on the wideband. Feel like I'm missing something or somehow my injector data is waaay off, but only in low IVT's. Everything is nearly good at 200F IVT and up, and perfectly fine at 300F, where everything in the cal is calling for lambda. Deatchwerks 72 lb injectors with their supplied data, in Whipple's manifold, on a stock long block.
I have an E38 for whatever it is worth.
Whether this is the only way to adjust it or not, it is a pain. You cannot just use a histogram of EQ Error in the software to copy/paste special, as you have to jack up the commanded EQ to get it to where it would have originally been commanded. I might be commanding an EQ of 1.1 to get the actual to run at 0.8, when it is at an IVT of 50-75F, for example. You always hear about someone "raping the VE", which is of course bad. But is it ok to "rape the IVT"?
here is my IVT gas table
Attachment 106239
just made a little correction to the IVT table. Pulled 10% from -40 to 132.8 deg then interpolated.
not quite as rich. I'll see how this goes for the week. Here is the modified table
Attachment 106242
Are you actually running AT the commanded EQ, and you are just trying to lower commanded? Or is it running lower(richer) than commanded as well? Also my wideband will only read down to about 9:1 (1.6 EQ Ratio).
My issue is that it runs WAY richer than commanded (and it commands very rich). I don't know how rich it really needs to be for a cold start and initial running. Here are my stock charts, interestingly different approach by GM with the figures
Attachment 106254
Attachment 106255
i did have a point where cold start was bang on not sure where i lost it tho, now WB reads leaner then commanded but still stays up n runs fine, gets to about 40c ect where the fuelling equals commanded then it's good from there, i think it's the right combo of all the OL, IVT, ITT tables to get it right