Table to tune out fat hot restart.

[albersondh]

What I have noticed. I went from OE pump to 255, cold starts are fine (E85), hot restarts just as heat soak has temps rising (2-3 min shut down) I would go fat enough to get mis-fire codes. Jump ahead and now Im on a 400lph, Weldon FPR and -8, the hot restart richness is even worse.... Im looking for a table to trim it back but cant find any that look like they would address the issue. Pulled cranking fuel above 194F back in the 2D table, but that realy does not address the issue. Is there a table for pulling fuel for warm-up enrichment above x coolant temp?
Have not logged this event but AFR's are 10-11:1. Does the pump run 100% during warm up? Any ideas for how I can tune out my hot restart problem?

Thanks.

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[NSFW]

My LGT's ROM has 6 tables to control cranking fueling, and all but one of them has an axis for engine coolant temperature (ETC). I would be that your ROM does too...

[albersondh]

All my warm up tables are zero above 154F. The only one I can think of that would cause this is "non-cruise warm up enrichment", and its zero well low enough that the extra fuel could not be coming from that table.

Ill get some shots of the tables I have to work with. I have been scaling my CL MAF, especialy the very low end. Today I did a long idle, 1st, 2nd, 3rd, and rescaled accordingly. Parked the car and attempted to replicate the fault with a 1-min shut down/restart, 2-min, 3-min, 5-min, and a 10-min cool down. I couldnt get the fault to replicate. Loging shows the fuel pump is 100% for the duration that it was previously going ubber fat, but now its compinsating quickly to keep me at sane warm up enrichment levels? Havent loged it yet but I imagine the car is in OL during warm up period? Maybe for the duration of 100% fuel pump?

[Cefaln452]

my car does this... not to the point of misfires, but starts up ****ty when hot

[NSFW]

Originally Posted by albersondh

All my warm up tables are zero above 154F.

Have you looked at the "Fueling - Cranking" tables?

[albersondh]

Originally Posted by NSFW

Have you looked at the "Fueling - Cranking" tables?

Yea thats the first place I looked. Pulled cranking fuel above 194F back in the 2D table. Didnt help at all, its a warm up thing, or at least a OL warm up thing. The issue lasts about the full duration that the pump is 100%. I bet this duration is all OL as well, since the possibility of running fatter than 11:1 is so great, the OE sensor wouldnt be able to read that..... Ill log pump and CL/OL and see what the overlap looks like. A lot of speculation I need to verify.

[WRXt4cy]

The issue isn't with cranking fueling, its post-startup. There are some tables and logic that richen up the fuel targets on hot starts. From what I have learned, Cobb has these tables defined but Open Source does not yet. I was having mis-fires on my car when I swtiched to E85. Watching the AFR's I was seeing low 11's at idle for about 10 - 15 seconds after a hot start.

I ended up disabling the misfire and p0000 codes for now until OS gets these tables defined and I can tune this out.

[albersondh]

I thought about disabling the codes but I like them their and dont mind clearing. I have been doing a lot of MAF scale work and that seems to have helped. I was a bit over 6% fat AFR error on the lowest g/s end of the Learning View scale. less than 1% everywhere else. Drove around in 1st and overlapped that with a bunch of idle time. Seems to have helped a bit, still not perfect but Im happy for the moment.

Went to log OL/CL status today and it just displays 8. 8 what? I dont get it.....

[NSFW]

Originally Posted by albersondh

Yea thats the first place I looked. Pulled cranking fuel above 194F back in the 2D table. Didnt help at all, its a warm up thing, or at least a OL warm up thing. The issue lasts about the full duration that the pump is 100%. I bet this duration is all OL as well, since the possibility of running fatter than 11:1 is so great, the OE sensor wouldnt be able to read that..... Ill log pump and CL/OL and see what the overlap looks like. A lot of speculation I need to verify.

Log "Final Fueling Base" as well. That will include all compensations, including undefined ones. If it turns out that this parameter is not actually going rich, then the problem is elsewhere.

If the ECU is in closed loop when it happens, look at the "CL Fueling Target Compensation A/B" tables under "Fueling - Closed Loop."

If it's in open loop, look into "Primary Open Loop Fueling Compensation (ECT)" under "Fueling - Open Loop."

At least, my ROM has those. Hopefully yours has similar stuff.

If none of those work for you, try starting at thread at RomRaider.com in the ECU Analysis forum, and include a log that shows the problem (including Final Fueling Base and OL/CL status).

[WRXt4cy]

Originally Posted by albersondh

I thought about disabling the codes but I like them their and dont mind clearing. I have been doing a lot of MAF scale work and that seems to have helped. I was a bit over 6% fat AFR error on the lowest g/s end of the Learning View scale. less than 1% everywhere else. Drove around in 1st and overlapped that with a bunch of idle time. Seems to have helped a bit, still not perfect but Im happy for the moment.

Went to log OL/CL status today and it just displays 8. 8 what? I dont get it.....

I wouldn't worry too much about the first fuel trim range as it can fluctuate quite a bit. It is the most sensitive area. As long as it stays below 5 - 7% it should be fine. I try to keep it on the negative side so its pulling some fuel.

CL/OL status will read 8 in closed loop, 10 in open loop and 7 during warm up or if your front o2 sensors has an issue and your ecu is refusing to run in closed loop. I think there might be some other status values but I can't recall what they are. These are the main ones you'll see.

If you log final fueling base as NSFW is suggesting, you will probably see it shooting for AFRs in the low to mid 12's. I think that's what I see. My wideband shows mid to low 11's during this time and I suspect that is due to the hot start enrichment table modifying or adding to the injector pulse width. With bigger injectors, the ecu is adding even more fuel that it means to.

[albersondh]

^ makes sense. If those tables are currently undefined then I would be going fat as per the OE table recommended values. Had a lot of cold start issue below 35F before applicable tables were defined and added to current RR revision..... My injectors are by no means huge (910cc) but enough to account for the fat hot re-start. Looks like Im hot starting in CL thanks for clearifying that. Ill try logging CL Fueling Target Compensation A/B. Appreceate you guys taking time to read and helping out a newb, thanks.

[Bamofo]

Ive been hounding Merp to look into this for me as well. Have multiple cars that need it. Soon i hope!