Anyone who is having Cold Start Issues

maiku · Post by **maiku** » Sat Oct 10, 2009 4:17 pm

I have a GReddy turbo kit which I used to run on the 370cc injectors at the 370cc tune. Since I upgraded to 650cc injectors and the 650cc tune, the car is very hard to start when it's cold.
I live in FL, so it's not even cold outside. (80+deg)
Needs to be cranked for approximately 7-10 seconds before starting, and when it does start it barely comes to life. It'll putter for a few seconds then run at a high RPM till it warms up and calms down.
I tried taking away fuel at startup and that seems to have made it worse so next time I'm going to add 30% to see if that helps. It's at -15% now and it seems worse.
I didn't look at the coolant temp where it gives problems, but it's about 80-90 deg in the garage where it gives me issues and the time interval where the issues return I'd estimate at about 1.5-2 hours before it gets tough to start again and probably 3-4hrs before it's full on PITA to start.

It happens no matter how full my tank is. It's done it every time since I upgraded to the 650cc injectors.

When I get around to changing it again to add fuel at startup I'll post back and let you all know how that went!

COMplex · Post by **COMplex** » Mon Oct 12, 2009 8:53 am

Hondata wrote:In your case a return to stock comparison is not possible. A datalog and calibration would help though.

Sorry for the delay. I datalogged my starting issues, and have yet to get them uploaded to my laptop, but as soon as I do I will post them along with the calibration.

If it helps, my tuner used the CT Stage 2 base calibration as a starting point for my tune.

Cold start issues started immediately after that, and he and I played with the cranking trim but nothing seems to make a difference.

Post by **Hondata** » Mon Oct 12, 2009 2:29 pm

I've added a section to the help file with more information about the way cranking fuelling works. See http://www.hondata.com/help/flashpro/tu ... g_fuel.htm

Looking at the datalogs, I think the cranking fuel is too low when cold. Here are some changes to test out:

- Return the cranking fuel trim to 0%
- For Race calibrations only, alter the water temperature compensation cranking to:

This should work for both stock and aftermarket injectors.

COMplex · Post by **COMplex** » Mon Oct 12, 2009 2:42 pm

Hondata wrote:I've added a section to the help file with more information about the way cranking fuelling works. See http://www.hondata.com/help/flashpro/tu ... g_fuel.htm

Looking at the datalogs, I think the cranking fuel is too low when cold. Here are some changes to test out:

- Return the cranking fuel trim to 0%
- For Race calibrations only, alter the water temperature compensation cranking to:

This should work for both stock and aftermarket injectors.

Do you think this will work in my situation as well?

Post by **Hondata** » Mon Oct 12, 2009 3:02 pm

I suggest you make the compensation tables changes, and then look at issues specific to E85 & your injectors.

COMplex · Post by **COMplex** » Tue Oct 13, 2009 4:45 pm

Hondata wrote:I suggest you make the compensation tables changes, and then look at issues specific to E85 & your injectors.

I will try making the changes you specified above and see if it helps the cold starts. I have also attached my calibration. I'll try and post my datalog of starting up soon.

The car runs and starts fine once it's warmed up and has been running great with the attached calibration.

Thank you!

soxfan143 · Post by **soxfan143** » Thu Oct 15, 2009 1:54 pm

I'm not having any cold start issues at all so I figured I would post up a log and calibration for Hondata to use for comparison. I hope this helps.

I'm running a modified GReddy kit with RC 650 injectors and a Walbro pump for a fuel system. I have a couple cold start logs.

soxfan143 · Post by **soxfan143** » Thu Oct 15, 2009 2:26 pm

Just to see what would happen, I just changed the ECT/cranking table to what Hondata suggested in this thread and did another cold start log and this time it fired even quicker. Within a half second to second it was fired. Starts better than ever. Great job again Hondata.

COMplex · Post by **COMplex** » Fri Oct 16, 2009 6:12 pm

Hondata wrote:In your case a return to stock comparison is not possible. A datalog and calibration would help though.

Please see the attached cold start datalog to go along with my previously attached calibration.

Let me know what you think... Tonight I will test the changes I just made to the compensation tables and report back.

Thank you!

Pir8pete · Post by **Pir8pete** » Fri Oct 16, 2009 7:28 pm

Hondata wrote:I've added a section to the help file with more information about the way cranking fuelling works. See http://www.hondata.com/help/flashpro/tu ... g_fuel.htm

Looking at the datalogs, I think the cranking fuel is too low when cold. Here are some changes to test out:

- Return the cranking fuel trim to 0%
- For Race calibrations only, alter the water temperature compensation cranking to:

This should work for both stock and aftermarket injectors.

I'm going to try this out aswell i'll let the car sit over night as it's -5C here now, and see what happens!

COMplex · Post by **COMplex** » Fri Oct 16, 2009 8:33 pm

Compensation table changes (per the tables above) didn't seem to make any difference for me :(

fuel trim is currently +25%
cranking fuel trim is +10%

rc 650cc / e85 / walbro 255 / 50~F ambient temp

hmm...

Pir8pete · Post by **Pir8pete** » Sun Oct 18, 2009 5:09 pm

did the added changes to the map without any success :( well it made it start a hair sooner but the problem is still very bad, heres my datalogs. I have included all three from that day cuz I can't remember the one cold start log.

Post by **Spunkster** » Mon Oct 19, 2009 10:06 am

You must post the calibration as well

Pir8pete · Post by **Pir8pete** » Mon Oct 19, 2009 11:38 am

Spunkster wrote:You must post the calibration as well

here you go

maiku · Post by **maiku** » Fri Oct 30, 2009 7:49 pm

I did this to mine with no luck as well. I'll try to get datalogs of it tomorrow!

edit: I got sick.. will do it when I get more time. x__x