Cold start tuning question?

[smug]

Can anyone explain to me that my car with a XP cam will not idle on a cold start with out chugging and stalling out? It has been doing this for a very long time but because I dont drive the car in the winter I have never tried to fix it but it is just something that I would like to take care of.

I have noticed that upon cold start it will lean itself out and start chugging really badly until it stalls out. If I hold the throttle around 1500 rpm it will be fine until the ECT reaches 70 to 80 degrees then, it will idle normally.

I tried to raise the idle for cold start to 1400 rpm and it does not make a difference to I returned that back to stock. I also adjusted my good fuel spark table back to stock from 1400 rpm down.

Major engine mods are that would affect this

XP cam
E85
60lb injectors
N* throttle body
LQ4 MAF
AFC
DHP tuner

Click to read more...

 

[Turbocharged400sbc]

comanded afr vs ect

 

[Turbocharged400sbc]

you have to experiment to find what it likes but eventually you can sort it out.

thing is to make your wideband power up/warm up fully before a datalogged cold start inducing a small vac leak can give you a temp lean condition to do a quick test if it wants to idle better leaner than your current settings, alternatly you can use a propane torch to add fuel temporarily.

once the countdown timer puts you into closed loop youll have to play with other tables but the iac idle speed vs ect is quite handy...its amazing what just a 25-75rpm bump will do

 

[Xfirez51]

Cold Start needs an AFR ~ 12.5:1 then lean out as Coolant Temps rise. Plus additional Spark Advance. I'm not familiar w Honda calibrations but a motor is a motor.

 

[Turbocharged400sbc]

 

[smug]

wait what honda

 

[Turbocharged400sbc]

the one with the xp cam

 

[10sec]

Get to work on your junk WaGN!!

 

[TommyGloves]

With E85...its going to be a PITA in cold weather. Like James mentioned.... commanded afr by coolant modifier table. Try adding a little bit more....maybe 5% richer and start from there. Until the engine warms up...the fuel will not fully evaporate for combustion. Unburnt fuel will show lean on a wideband.

Keep timing stock.

How old is the e85 in the tank?

 

[Xfirez51]

wait what honda

Oops! Read Honda in the sig.

 

[smug]

With E85...its going to be a PITA in cold weather. Like James mentioned.... commanded afr by coolant modifier table. Try adding a little bit more....maybe 5% richer and start from there. Until the engine warms up...the fuel will not fully evaporate for combustion. Unburnt fuel will show lean on a wideband.

Keep timing stock.

How old is the e85 in the tank?

Right now the e85 is from last fall. My low fuel light is on so a fresh tank will be soon

 

[Turbocharged400sbc]

:retard:

 

[1quick]

My turbo car would legit not start at all under 35* it would crank until the battery died, has a little to do with the vapor pressure of e85 vs gas/ In the winter they blend butane in the gas to raise the vapor pressure and make cars start easier ethanol has a lower vp than regular gas so starting is even harder, mix new stuff in ASAP last year I left the car sit with e85 and I tested it in the spring the car wouldn't even start on it it absorbed so much water over the winter the test wouldn't come out it was so bad

 

[Turbocharged400sbc]

it started... what.... like 40 times?








:trollface:

 

[smug]

My car acted the same way in 93 pump gas last year during the winter, so...

 

[Turbocharged400sbc]

its broked

 

[smug]

3800 garbage

 

[1quick]

It's find put a little bit of 93 in with the e85 and it will start easier, or just wait till it's warmer out to start it

 

[Turbocharged400sbc]

the TR cold starts like shit unless i piss into the turbo inlet

 

[DEEZUZ]

Mine starts and dies when below 30 and the Motherfucker is stock...

 

[smug]

I set the commanded AFR to 12.5 and set the idle to 1100 rpm in my problem area and seems to be doing a little better. I have to let it cool down and try again.

 

[AjL227]

I have a similar issue with my junk.
I prime the pump twice, then crank while adding a bit of fuel.
I prime the pump a few more times, then it usually starts right up.
I've just dealt with it. 3800 garbage indeed.

 

[shaferz]

Holy shit - kinda proud of my GTP after reading this thread. Fucker loves cold weather (other than rusting brake lines lol)

 

[RICH17]

You definately need to throw some 93 in there before winter smug.

 

[GTPpower]

Does it fire off right away? Just has trouble running once it's already started?