So I have been playing with E85 for the last few mons. 1st car was on a AEM.

What I have seen is it likes almost no fuel for cold starts. So on stock ECU the only way I can think to pull fuel for cold starts is air temp which works great on my car since I do not have a air box and the only time it will ever read that cold is when the motor is stone cold in the morning.

My only fear is if I tune a car this way that has a stock air box and thay are in freazing temps it may read to cold and make the car lean.

The only area I have to adj for a good start is under 50deg.


So has anyone ever logged intake temps under 40deg on a hot motor?

Or does anyone know how to change cold start fuel buy coolent temp?

 

In cool weather, my logged IAT will read ambient air temperature within a few seconds of starting the car.

 

Yes, it all matters if you're blocking the engine bay heat from your intake or not.

I remember logging just a couple of months ago when it was cold (below 0) and my intake temps were below 0, too.

If you have an open cone filter sucking in the heat from the engine bay, then it will obviously be much higher.


Eric

 

So Lucas and I are local to each other and meet on a semi regular basis. To fill everyone in on what we are thinking this is an E85 issue that will eventually affect anyone on E85 AND in cold weather.

E85 DOES NOT like fuel on a cold start on a cold day. You cant take enough fuel out and get it to start. You gotta crank on it and crank on it to get to light. Taking fuel out via the accel enrich table at low speed helped, cranking more timing in at idle helped, but is there any pointers to closed loop cold start fueling? Is the ECU using anything that is configurable that we already have access to or is there something not yet covered?

One thought I had was to set the Min Temp for closed loop to something like 40*C and then the car would start in open loop and you could take fuel out (I think). I do know from experience that this sets off a SES light to the affect of Min Temp Closed loop is out of range (or similar). Any ideas?

 

Really it is just the 1st start of the day. Once started not a big deal the car will bark off very easy once the car has even ran just for 2sec. So we just need to be able to remove fuel buy coolent temp.

The air temp way is working great but not the best way if you still have stock air box or cold air intake.

I dont think any closed loop stuff would work well for starting. Once started even with the air temp set to stock it will idle and run fine its just the 1st start of the day ware it needs less fuel.

The cold start seems to be about he only picky thing about E85 other than that it is way more forgiving than gas for cold runing. Anyware from 11-16sAFRS on a cold motor drives great.

 

I never had any problems with cold start other than an extra 2 or 3 cranks. This was in single-digit weather with a mini-battery. I didn't really do anything special to get it to start.

-Paul

 

I would think in those kida temps you would be on E70 we never did have a winter blind around here.

If this is on a Stroker it my need just enough more fuel than a 2.0 to not cause a problem. On my car though with the fuel pulled out out buy air temp it will fire on the 1st crank.

I have also tuned 1 AEM car on E85 and it is the same way but I can tune the AEM when cold so that car starts very well.

 

This was before the stroker. I had a stock block with HKS 272s. It probably was a winter blend that I was running, as will likely be the case with others facing similar temperatures. It usually took 4-5 cranks to get the car to fire up, but it usually takes the same with gasoline in those temperatures.

-Paul

 

Brining this back from the dead as i need some advice on cold starting adjustments to the aem.

Mine takes a good bit when cold and Sean my tuner had askes if i could get some tips and i know bot you Lucas and John B have much more experience/knowledge on the subject so i hope you guys see this.

I'll pm you if i don't hear back today or i'll give you guys a ring when i'm out of real work and at the shop this afternoon.

Everything else is great on the car except for the cold start issue.

So i take you advise to remove fuel for start up via the int temp as i'm don't run a stock air box.

 

I guess the interesting thing is that everyone here is saying less fuel while cranking, but everyone in this more recent thread says more fuel while cranking/cold:

https://www.evolutionm.net/forums/sh...&postcount=123

I'm curious too, as I used The method described in that thread and was thinking of bumping the really cold temps even more since I'm having so much trouble with the recent chicago cold bout.

 

yes the lower coolant temps you really have to bump up the cranking IPW more than you think you should.

 

Weird, my car will only start if I dump LARGE amounts of fuel when cold..

 

some of the aftermarket e85 conversion kits have temp. sensors in them and dump extra fuel in to aid in starting when cold as well. FWIW

 

Patrick,

We have been doing a dyno day this weekend so we'll back in the shop monday.

Lucas told me that you need to look at the following tables in "Engine Start"

Crank injector time table will be flat versus TPS this needs to have a big spike at about 24% and taper off toward redline for extra fuel.

Crank Advance needs to be upped to 25-30*

Then go to advanced engine start

Start extra decay and Start vs temp need dropped and then the initial crank pulse needs upped

stock computer E85 start is usually what it will be though...starting fluid...lol

 

The cold starts have been touchy for me. On E98 much under 60deg I cant get her to start with out help, E85 seems to be real hard much under 40 deg and E70 all ways starts great.

This one is flat most of the time. I like to set it up so I can crack the gas and have it bark off good. You will find the crank inj tables do alot with small changes. So I find it best to start low and go richer. To much and you can flood it out quite easy.