AEM EMS cold start problem.

Joined
8 September 2009
Messages
182
Location
EL PASO
AEM EMS cold start problem. FIXED!!!

Hi since I got my car AEM EMS installed and running had a cold start problem, it will start only after 3 or 4 tries every time. After starts the problem goes away and it will start fine, but if engine cools down like overnight then the problem comes back.

I was told and also read on the AEM forum to increase fuel at the warm up enrichment map, I wanted to try the AEM warm up enrichment map which shows more fuel than mine but not really sure if this is the best route to take.

Does anyone has a warm up enrichment map that will solve this or suggestion for this problem?
I thank you in advance for your comments.:smile:
 
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Thanks for your help a combination of some settings from other people inputs and my own setting gave me the correct setting to start my car right away during cold start stage in the mornings, is just wonderful to see and hear your car starting strong the first time with the AEM in cold weather.
Thanks Tinker219 :smile:.
 
Today had a chance to test mt cold start settings, we have snow here in El Paso and temp dropped to 33 degrees, I know is not very cold but my car starts right away like the OEM :).
http://www.youtube.com/watch?v=9pp4sTZEbaU
 
Yes Mike it really did, :smile:thanks like I said it took a combination of settings included yours, Tinker219 and mine, what I did basically is just every morning I made one try on each different change on the "cold stat settings" and at the same time study the sequence of the start up procedure, till I got it to a very close point then I made a change that got it to work as the OEM cold start (well very close):cool: but I thank you both guys for your help, I understand that for this part of the tune is no the same as the main fuel mapping, since you guys (Tuners) only have 1 or 2 days to get it right, and in some cases just hours and like in my case "email tuning" :redface: is even worst.
 
Yes Mike it really did, :smile:thanks like I said it took a combination of settings included yours, Tinker219 and mine, what I did basically is just every morning I made one try on each different change on the "cold stat settings" and at the same time study the sequence of the start up procedure, till I got it to a very close point then I made a change that got it to work as the OEM cold start (well very close):cool: but I thank you both guys for your help, I understand that for this part of the tune is no the same as the main fuel mapping, since you guys (Tuners) only have 1 or 2 days to get it right, and in some cases just hours and like in my case "email tuning" :redface: is even worst.

It's running a CT supercharger too?!? Thats awesome! Do you have a link to a build thread or anything?
 
HERE
Is kinda of long since I started more than year ago :smile:
 
I know that every car needs a different Mapping, but for anyone having cold start issues with the NSX my cold start setting might help, like people that are located in very cold areas.

My mods are low boost CTSC, 440cc injectors, and external fuel pump rated up to 500HP.

These settings makes my car start on the first crank like OEM at 23F after sitting for 3 days in cold weather also starts right away on warm weather after engine has reached normal operating temperature.

If anyone wants to use these settings for cold start and modify to your mods and engine needs you are welcome to use, I have posted them in the AEM forum, HERE is the link.
 
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I initially had cold starting problems since the car was tuned, well, at 85F in California.

Took it down to Mike, he tuned it based on gut and experience, and now she starts every time. Awesome.
 
I'm bookmarking this page.

My car's cold start is brutal, and I've livd with this issue for over a year. Took it to my local tuner who originally set up my aem to run in warm 70-85 weather and he said there's nothing that can be done for it since it's an aftermarket ecu.

I'll try out the posted map this spring when the nsx comes out of storage, keeping fingers crossed.
 
I'm bookmarking this page.

My car's cold start is brutal, and I've livd with this issue for over a year. Took it to my local tuner who originally set up my aem to run in warm 70-85 weather and he said there's nothing that can be done for it since it's an aftermarket ecu.

I'll try out the posted map this spring when the nsx comes out of storage, keeping fingers crossed.
I understand your frustration, I'm also noticed that a lot of tuners and AEM users think that cold start is impossible to achieve with aftermarket ECU's, just try those settings and see if they work for you.
Some even switched to other brands cause there's the assumption that AEM is bad on the cold start.
 
Ok I have couple of questions for you.
Will the car need to be tuned again after I adjust all these setting you have posted?
My NSX has two issues, first it takes about 2 to 3 turns for it to start, then once it starts up when cold I have to keep my leg on the gas peddle till it warms up or else it idles rough and dies. But once it's warmed up it's perfect, idles fine and drives fine with no issues.

My set-up
3.0 stock motor
BBSC 8 psi
rc 550cc injectors
stock fuel pump
Science of Speed BBTB
custom ported intake manifold and removed VVIS
Top speed headers
DC exhaust
test pipes
Car made 400whp, drives and runs perfect. Only issues is cold start and cold idle.

Thanks
Rahim
 
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I don't think so, unless your present settings are close to pig rich and you change the "FUEL ENRICHMENT TABLE" will get you to pig rich in certain temperatures but I honestly don't think so, since you only play with the "cold start settings" you actually don't change anything on your main fuel table.
Its very safe to change some of the cold start settings but ANY CHANGES YOU DO, ARE DONE ON YOUR OWN RISK.
 
I'm bookmarking this page.

My car's cold start is brutal, and I've livd with this issue for over a year. Took it to my local tuner who originally set up my aem to run in warm 70-85 weather and he said there's nothing that can be done for it since it's an aftermarket ecu.

I'll try out the posted map this spring when the nsx comes out of storage, keeping fingers crossed.

Wow , get a different tuner...
 
Some tuners don't have enough AEM NSX tuning experience, and some don't even have cold weather to learn to calibrate for very cold weather start, and on top of that they don't have the time since you only have one chance every morning.
 
Some tuners don't have enough AEM NSX tuning experience, and some don't even have cold weather to learn to calibrate for very cold weather start, and on top of that they don't have the time since you only have one chance every morning.

That explains why my BBSC with the AEM Fic starts so good in the cold. Cody from LoveFab, who tuned mine, lives so far North he doesn't see green grass until July:tongue:
 
I know that every car needs a different Mapping, but for anyone having cold start issues with the NSX my cold start setting might help, like people that are located in very cold areas.

My mods are low boost CTSC, 440cc injectors, and external fuel pump rated up to 500HP.

These settings makes my car start on the first crank like OEM at 23F after sitting for 3 days in cold weather also starts right away on warm weather after engine has reached normal operating temperature.

If anyone wants to use these settings for cold start and modify to your mods and engine needs you are welcome to use, I have posted them in the AEM forum, HERE is the link.
I know this is an very old thread. But is there any way you can send me the link or files for the settings. My car wont start when its 26° or lower out. TIA
 
I know this is an very old thread. But is there any way you can send me the link or files for the settings. My car wont start when its 26° or lower out. TIA
Have you received a response? If not, reach out to Mike @ Autowave...he may be able to help you.
 
I have the same issue with my Infinity. Works great when warm but when it's 40 degress or colder, it doesn't want to start. Any pics or info on what on updating the start up maps would be great.
 
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