6']['9

iTrader: (2)

like the title says. when i come to a complete stop the idle goes from about 1100 to 500 then if i dont keep the idle up it dies. Its been doing this for some time. I a MS4 with the LS6 heads & a TSP tune. I replaced the 02's, & the MAF, & the TPS then cleaned out the TB, im thinking its going to be either the spark plugs, wires, or maybe a vacuum leak but i dont know where to start.

Also early in the morning itll i can start it then it dies, start it again itll surge then die. Then about the 4th or 5th time it may catch then stay at about 1100. When i leave for work it drives fine but at times it will drive then feel boggy and if i press the gas it just goes. I really dont think its the tune cause its been fine and just started this around april or so. I have EFI live but have no idea on how to use it and the EFI live site isnt very much help on what to do. So id appreciate any suggestions

thanks

OUTLAWZ RACING

iTrader: (9)

Sounds like fuel pressure how long ago have u replace the fuel filter? Is the pump making noise?

6']['9

iTrader: (2)

i replaced the fuel filter about a month ago, and ive never replaced the pump. the pump only makes the initial noise when you turn the key then it goes away after a few seconds.

OUTLAWZ RACING

iTrader: (9)

Check for vacume leaks use carb cleaner around the intake and vac hoses and listen for a change in RPM.

Bird-Of-Prey

iTrader: (23)

IAC motor working?

LS184

iTrader: (7)

have u checked your fuel pressure?

5.3LJimmy

iTrader: (10)

Could also be an exhaust leak.

massls1guy

iTrader: (9)

Did you ever get a real (not mail order) dyno tune?
https://ls1tech.com/forums/showthrea...306&highlight=

After my cam install I got a good tune. We went out for a ride, I was in the passenger seat holding the laptop, he drove and watched the graphs on the screen. He pulled over maybe 4 times and adjusted the tune for my setup at part throttle, full throttle, etc and really dialed it in.

LS1Formulation

iTrader: (13)

My car has the same problem... my IAC was maxed out. When cold, the engine could not get enough air to keep the car running. Cracked open my throttle blade a bit and problem solved.

6']['9

iTrader: (2)

ill try that.

6']['9

iTrader: (2)

should be i replaced it a year ago when i did the HC install dont know how to test it tho?

i have not tested the FP cause i dont have a gauge where the billet fuel rails are. I never purchased one and now im wishing i did.

It could be an exhaust leak as well but i dont know how to find that either.

As far as the mail order tune, thats all i have. I didnt want to fork out another 500 for a dyno tune. But even after i got the mail order tune the car ran like a champ for months. now its doing this.

Man i need to learn how to multi quote.

6']['9

iTrader: (2)

how did you do that?

Lt1Porsche

iTrader: (6)

well an exhaustleak wont cause that problem. id bet its either a vacuum leak or your iac. fuel pressure wont cause that problem either

eamador11

i agree, your tune is all messed up; plus its possible they sent the wrong tune file. Contact Charlie@RPM Motorsport; hes the best mail order tuner that can tune anything and get real close without seeing your car. he charges 150.00 i believe.

6']['9

iTrader: (2)

well if it was the tune and i got that done over a year ago why would it start doing it now. I dont even see how a tune thats in the computer would just go bad. Im going to check the IAC and maybe try looking for a vacuum leak.

Patrick G

iTrader: (14)

Your PCM has learning adaptives. Your short and long term idle trims will eventually try to get your IAC counts where they should be stock. When this happens, you'll have dying and other nasty stuff.

Try this, zero out all L-trims, then start drilling your TB blade or cracking it open until your IAC counts are between 30-60 at idle with the AC off (engine fully warmed up). Once that's done, you can start dialing in your running airflow in gear. Trust me, getting the IAC counts in that range is key to good running.

6']['9

iTrader: (2)

pm sent

DaddySS

As Patrick says, there's a good chance you just need to get iac correct. If you have efi live, step one would be set up a scan including iac, throttle position, and stft. You'll have a much better idea of where you and what you have to do.