Cold start Woes...

[SEC]

Hi, i am new to this tuning aspect, but definitely not to building cars. My son and i swapped a 1st gen s10, bought a mail order tune from a respectable shop. Well it has not been fun, i filled out the paperwork for all my engine/trans. 5.3 BTR stage 4 truck cam 8.1L truck injectors, cable throttle, stock MAF, 3400 Precision stall, 4L60e, all needed. I received pcm back, put in truck, starts idles, till closed loop then i lose everything. O2's wont read, throttle does not read... found out when i purchased the credits for it, he had tuned it for a manual, 6.0L car. I tried segment swaps, nope, bought complete auto tune off repository, and it works. Never got email back from the Tuner, tried more than one email address too. Now it runs great, drives great, used the Bluecat trans tool, worked great, but now it is colder, and truck will not start below 50*F. It hits once and dead, then just cranks.
Have to feed it 1/8 throttle or so till it hits 50* then it takes off on its own. I have tried a few things i read here, but to no avail. Just hoping someone can send me down the right path.
I have them attached; hope they show up.


1st tune is the tune i got to work with the car auto and paste all engine parameters.
2nd tune is after bluecat trans tool, and me trying things i have read on here.
Then couple cold start tries.


not sure if it worked.

[Alvin]

Who are these email tuners that are just leaving customers without communication?

By the sounds of it.. this is a throttle body set up issue. With a cam or other mods. The engine needs more air than the IAC passage can provide. Really the flow around the blade and the stock hole in the blade should set the minimum amount of air the engine will need and the IAC passage will trim arond that.

Log TPS Voltage, IAC counts and LTIT and STIT (long and short term idle trims)

The big thing to focus on right now is making sure the IAC is in range.. So fully warmed you'll want it to be between 30-60ish counts at a idle in gear. If your higher than that I'd recommend taking the hole to the next size up (1/32 at a time)

[SEC]

Ok, i looked back at my logs. It shows 0 on my idle air control channels. I looked at earlier logs and it was working, i remember setting my throttle blade to get it right, then resetting tps to 0. Now it shows 0 on idle air control, could that be my problem? I know sitting with koef you can sometimes hear the iac move, small fast clicks.
I deleted the channels, added them again, i will log again as soon as son returns from college on weekend. If you all respond, i will answer as i am watching this for ideas. I know when you start it you hear the big loud sucking thru filter like iac is open, goes away as warms up, i figured it was iac. We will see i guess ...thanks to any and all who throw out ideas...much appreciated.

[Alvin]

The best way is to get it on a log so we can look at it.

[SEC]

I posted 2 logs and it shows idle air 0. Also posted 2 different tunes. The tune before I adjust trans, and tried adjusting for cold start.

[HATEHPTUNERS]

your olfa table is JACKED. You have short term fuel trims turned OFF... STFT DISABLED. Your short log is showing that you are excessively lean-which may or may not be correct as we are not sure if the fuel injector data is correct. Low octane spark table is jacked. VE table appears to be stock. The BRAF table has some really high numbers in the lower temperatures that taper off pretty drastically as the temp cells increase. I think I would find a local tuner to start dealing with as there are some serious issues that need to be fixed with that tune. The learning curve to get you up to speed... is going to be time consuming.. if you want to try and tackle it yourself; https://www.youtube.com/watch?v=423ZMUHPRu4

[Alvin]

I posted 2 logs and it shows idle air 0. Also posted 2 different tunes. The tune before I adjust trans, and tried adjusting for cold start.

Really need the other stuff I asked for logged but I spot the issue.

The idle airflow vs ECT table is too high. When you get too high in this table the IAC doesn't open at all.. in fact it closes.

This number is around 39 g/s for F-bodies. and either 34g/s or 29g/s for early trucks.

[SEC]

Ok. I see that. Thank you. I watched the video that was posted, good stuff. I’m learning, probably be learning for years, but this is so interesting and makes a guy feel like he is doing something when you can see/feel the difference. Thanks. Soon as I can get to truck I will be changing some things.