I know this has been discussed many times and the issues have had some resolution. In building up the 94170715 rom I made a small "discovery" if you will.

Looking at the Injector Cranking Enrichment IPW (Main) it appears that the colder the engine is the more pulse width is added, thus more fuel.

So....in theory all that needs to be done to guys with e85 and starting issues is to raise the values a smidgen.

I also noticed that 9417 values are much higher than 9653 which would explain why 9417 does not have the cold start problems of 9653 because more fuel is dumped in in the 9417.

Make sense???

 

All i do is turn my ignition to on (but not crank for 15 seconds) then crank it. Works for me, ill have to look at these rom values and see what i have.

 

You might want to look to mrfred's advanced fuel control options thread for more descriptive names for this stuff; mrfred went to a lot of trouble to document this properly, and it would be good to give ourselves a common language to refer to it with.

(We've named and renamed these particular tables so many times at this point as people figured out the side effects through trial and error that it's hard to tell what table you're talking about, so including a table address would be helpful. I mean that as a general thing, I don't mean to single you out on this; a ROM ID and table address combo tell disassemblers a lot more than just a textual name.)

Depending on the address you're referring to, it could either be the one mrfred referred to as "UCOMP", or "Cranking Primer Initial Pulse". If it's the latter, that's a pretty well-known table for fixing E-85 cold-start issues; you didn't discover anything new, I'm afraid. If it's UCOMP, you might be better off leaving that table alone. (It's more of an internal bookkeeping thing; I suspect the results of changes to that table will be somewhat non-deterministic. They'll have an effect, but not as repeatable an effect as changing the proper cranking pulse table.)

 

Thanks for the clarification Ed.

I've not gotten too into e85 tuning yet. There just isn't many pumps in my neck of the woods. I just though that this might help being that the common trend with e85 is cold starting.

Here is the xml for the table for 8653 and 9417....

 

Ah, okay, that's what mrfred referred to as "Cranking Primer Initial Pulse". It's the map of choice for improving cold starts on E-85. In fact, so much so, that tephra made it an alt map.

(Although, I should point out that the address for that coolant temp axis of that map in 96530006 should be 69D8, not 69BE. The address you have for 9417 is correct.)

 

So I was correct in my "theory"....cool beans.

My 9653 is the v7 version that was posted in the v7 thread. Acamus also said there are some other addresses that seem to be wrong too.

 

Here's my fuel settings for the cold start doesn't get much below 20F here though so I dunno how much it will help. So far one crank and fire no matter how cold or long it sets.

 

Yup been using the cranking IPW adder table for almost two years now so that my personal Evo 8 cranks first time on E85 even in these conditions:







- Bryan

 

^^^ Why not park in the garage in front of you? lol Sorry just point it out


Respectfully,

Evan Smith

 

Probably because there are other cars in there!

Logically,

Scorke

 

The point of this thread was to highlight the solution to e85 cold start issues. I knew when I posted that the problem has long since been solved....I just wanted a place to put the solution because searching can sometimes prove difficult.

Thanks for the input.

 

lol I know there had to be a logical reason but what other car could be more important than your evo? Unless GST was just trying to work on the extreme cold start issues


Evan Smith

 

Did mrfred define the table that deals with fueling for the few seconds after the engine starts? I think there was one before it hits open loop, I don't wanna sound like a tard haha.

It starts fine for me and when it warms up its fine, but the time after it starts up it goes really lean and makes the idle drop to sub ~400rpm and then jump back up repeatedly. I'm currently on SD and I'll re check/adjust my idle afr's in open loop when its warm just to make sure, but I'd like to know of that other table just in case.

 

anyone have those xml's for the 8859?

thanks in advance

 

<table name="Cranking Enrichment IPW Adder (Main)" address="52b2">
<table name="Coolant Temperature" address="6ff8"/>
</table>

The def for the alt map is different.....the one above is the normal 8859 which is already included in the stock xml/bin

Here's my IPW tables and I have NO issues with cold starts what so ever.