ECMlink Hard Start After Shutting Down a Couple Hours

[90 TSI FWD]

I posted this in the link forums, but it doesn't hurt to ask here, too!

Ever since I switched to SD and E85, I've been having a problem with "warm" starts. I say "warm" because the car could be cold... okay, let me elaborate.

My car will start immediately in the morning, OR after it's been sitting <1 hour or >~10 hours. I don't know what is causing this, so I'm hoping someone here would have a good idea.

I first thought this could be a warm start issue, so I adjusted the CrankingFuelAdj to both ends... like super high and super low. Nothing changed the way it started. I also messed with the InjBatteryAdj around 10V (starting voltage) both up and down, but that did nothing. Then I changed both Coolant Temperature Sensors, just because. That did nothing. I changed the spark plugs - nothing.

I thought this maybe could be a temperature issue, but the problem still happened after work one day when the car was cooled down a lot (<20 deg F outside).

My next shot was perhaps a leaking injector. I sent my 1600's to FIC and after a cleaning, it passed their tests. Then I thought maybe the fuel pump wasn't turning on. Since I had no one to watch my AFPR, I recorded the gauge while I cranked the car and it jumps up immediately when and where it's supposed to.

I'm hoping I missed something that maybe someone can see. I hardly drive the car just because it's kind of embarrassing holding the key on start in public places.

Bytheway, you'll notice I hold the throttle when it starts because it'll shut off. I've had to do this ever since I removed the FIAV years ago.

 

[luv2rallye]

Sounds like vapor lock. See here: http://www.dsmtuners.com/threads/vapor-lock-hot-start.217349/#post-1821514

 

[tmoney20g]

Running FIC 1100 hi-z, and having pretty much a brand new setup, I'm starting from scratch w/ motor/v3 SD setup. I have a rough start condition when cold, so my "tuner buddy" and I have made some adjustments to the coolant temp fuel adjust in the DA tab. I did notice a difference and well, upon my final start-up last night, I had a cold-lean condition, so we have to dial that in. I did have an overly rich start-up condition, so at least I know it is making adjustments and reacting.

But, typically that table reaches zero as the coolant temp rises. But with your bigger injectors, just take a look at what the coolant temp is when your problem condition happens, could need some adjustment to this same table as well.

We didn't touch my cranking adjust at all.

 

[gofer]

Hard cold starts are something you've got to deal with running E85, there are a few things that ECMLink controls that can improve them though. Not fix, improve.

You've already played with the coolant temp tables, I recommend turning those back to stock and using the below methods since the coolant table applies fuel adj. based off coolant temp all the time and below only controls fuel settings while starting.

• Engine Priming Squirt - Let's you adjust the initial fuel squirt of the injectors after each attempt at cranking the motor and, in my experience, the more fuel in the CC the better when cold starting. This is something you can play with though, 0 disables fuel prime and 100 is full stock prime. Just click the link below to download the file you need to install the DA file...
  • 1g DSM
  • 2g DSM
    • Here's the Wiki procedure to help you install/set it up properly --> DA Access Changes
• Cranking Fuel Adj. - I read that you've already played with this but this table is great, sucks it didn't work for you but maybe it's a combination of things. I recommend you increase fuel across every temperature range, my car seemed to like an increase of ~60, i.e., the 46F cell from 80 to 140, etc.
• SD VE Table - Capture a log of you cranking the car trying to start it, then use the track data log feature to see which VE table cells are being used while it's cranking. Increase the value of those cells to richen up the fuel mixture while cranking.
• Use the gas pedal - When you open the throttle completely using ECMLink it enables fuel cut to the injectors. I've noticed that if I pump the gas pedal, similar to starting my dad's old carb'd Ford pick-up, while I'm cranking (with all of the above done too) the car starts up on the first cranking attempt even when it's 32F outside.

Try the above and see how it works out for you.

 

[90 TSI FWD]

After the struggled warm start, the car will start right away for the next hour after if I shut it off again. It doesn't sound like "vapor lock" described in that thread, especially because this problem happened in cold weather 8 hours after the car shut off. Thank you for the suggestion though!

Gofer, I think you mixed both mine and tmoney's issues together. I don't have a cold start problem. The car starts right away when it's cold; sometimes in less than half a second of cranking.

In the Engine Priming Squirt, it looks like that only functions after attempting to start more than once. That wouldn't help the problem during the first crank, which is what I'd like to fix.

For the CrankingFuelAdj, you can see I already tried adding fuel. I also tried taking it away. I still had the warm start problem.

I actually thought about increasing the cells in the VE table. How much should I increase it by? Or maybe I should decrease it? I have my doubts about this doing anything, but it's worth a shot.

My Global injectors are dialed in about 5% more than suggested. Could this cause the issue?

You can also see from the logs that I do use the gas pedal while I'm cranking. While pumping, should I pump 100% to cut fuel for a second?

Again, my problem is warm starts and not cold starts like I think you may have been thinking from your post above. Thanks for your input!

 

[gofer]

You're right, I did misread your issue but the engine priming squirt DA table is worth a shot. It controls the INITIAL squirt of the injectors during the initial crank of the motor, not after... The first crank of the motor meaning, when you turn the key it controls the initial fuel squirt of the injectors into the CC for that cranking evolution. Once you cycle the key (assuming the car didn't start) and start cranking the motor over again it will effect the first fuel squirt of the injectors again. Worth a shot...

1. If it's a warm start issue then maybe your CoolantTempFuelAdj table's your best bet, I'd keep a notepad (on paper or on your tuning computer) and start recording your coolant temps prior to attempting to start the car. If it seems coolant temp related, i.e., hard starts "warm" between 80* - 150* CT's then play with the fuel adjustments between those two values experimenting with adding/subtracting fuel from the mix. Instead of generalizing "warm" hard starts it might be helpful to find out if it relates to coolant temperature, figuring out that window (if there is one) of where CT's are when it starts hard and where CT's are when it starts right up.
2. You're saying the car starts when it's cold (>10hrs) and hot (<1hr) of running but, once you finally do get it to start when it's "warm" (even though it starts hard) have you ever tried shutting it back off and starting it again? Just curious if it still hard starts since it's "warm" or does it start right-up since you got that initial hard start out of the way...
3. It might seem completely unrelated but you might do a quick compression check.
4. You're saying you did two things to your car prior to running into this warm start problem, switching to E85 & SD. Switching back to running a MAS would be a PITA but try filling her up with a full tank of 91 and see if the problem persists, eliminating if it was the SD upgrade or the fuel switch.

Sorry I didn't look at your logs because the computer I'm on doesn't have ECMLink, if this goes unresolved I'll pull out the laptop and take a look tonight.

 

[90 TSI FWD]

Just to give a long-awaited update: It wasn't until recently that I decided to try and fix the issue again. I came across this thread on DSMTalk: http://www.dsmtalk.com/forums/showthread.php?t=234599&page=3

I added a LOT of deadtime to the 10-12V batter range, which is where the battery voltage drops to during cranking. So far this fixed the problem, but if it returns, I'll update this thread. I now have a new problem I'll be creating another thread for. Thanks for everyone's input!

 

[enriquez2000]

I actually had to decrease my coolant temp adjust dramatically on e85 for some reason. My car would try and idle at 9afr.. and choke. Now it fires up at 10.5 and quickly drops to 12 until warm. Never can i get it to start 1st try.. usually takes 3 attempts on a cold colorado morning.

But my point is sometimes you have to go the opposite way to get things to work right.