Ok guys and gals... Ive used the search feature and it helped, but couldn't find a definative answer for my issue. First, Here's a little background. 2000 TransAm WS6 M6. Just replaced the motor myself with a fresh forged 347 mill from TSP this Jan. The Mods:

-TSP Torquer V3
-Stage 2.5 5.3L heads
-F.A.S.T. 90/90 (unported)
-RAM clutch
-Pacesetter LT's/ SLP LM

I assembled the long block myself before the install. Did everything by the book to the specs. The old motor had a stock bottom end, Torquer V2 and a set of stock type ported heads. It had approx 70k on the odometer when it took a dump. The number 7 intake valve ended up punching through the piston on my way to work, cracking the sleeve and block (Im guessing due to a bent valve that finally worked its way loose) hence the engine swap.

When I did the swap I reused the old injectors and all sensors/ wires. I had it tuned at a reputable shop in Bowlinggreen KY, on a Dyno Jet and she put down a stout 454/405 corrected but was running out of injector on the top end. I was very happy with the power and results however; he couldnt get the idle right. He kept drilling out the throttle blade hole (I thought a bit too much), it helped a little, but still she's got issues. He told me to put some miles on it, the computer will eventually learn and compensate for the new mods and if it didn't get better to bring it back and he'd take care of it.

It idles normally when cold untill the vehicle moves... Once the vehicle is moving and the clutch is disengaged the idle revs to about 2500 and stays there untill the vehicle comes to a COMPLETE stop. It reapeats this cycle until the vehicle is warm. Once warmed (about 5 min of driving) and the clutch is disengaged with the vehicle moving, it won't hold idle at all. The only way the car won't die is if you feather the throttle untill the car comes to a complete stop, then sitting still it will idle perfectly. If the car dies at any point it starts the entire process over again as if the car was cold. 3,000 miles later, I haven't been able to get ahold of the tuner. If anyone has any answers or if anyone is in the Ft. Campbell, KY area that can help, it would be MUCH appreciated. Right now im deployed and the wife is trying to drive this thing around town as her daily driver... Momma aint happy!

Sorry so long winded, just trying to get all details out on the table. Thanks in advance.

-Zach

 

Well, idle tuning is the hardest. It's hard to know what the problem is if you don't have software or know someone who can help. It has to have enough air from the TB to get IAC counts in the ballpark, idle airflow has to be right, and from there the cracker and follower tables can be very time consuming to get right, with a combination of finding the right spark. This is assuming fueling is correct. It's also possible you have a vacuum leak. Guess I'm not much help other than to say it's not a simple problem to fix and you have to have software to do it.

 

Well, im almost 100% positive its not a vaccum leak. I do remember the sensor that fits in the back of the manifold (I think the MAP sensor???) was not as snugg as I would have liked it to be. It just kinda sits in the hole. But I checked it afterward and talked with other FAST owners, this seemed to be the norm. Other than that all other lines are either capped or pluged in.... It sucks. 8 grand and the damn thing still wont run like it should. Guess I better start learning how to use tuning software....

 

i have the same problem right now with my car i have the TRAK cam which is similiar to yours and sum times it idles great at around 900 rpm and most of the time it tries to catch its tail like it goes down to 500 rpm n then up to 2000+ and back down n back n forth n then normally dies.... and then when i have to put mine in rev. it normally dies or i have to drive it like a stick n hold a foot on the gas n brake at the same time.... it pisses me off and it runs ok when we get done tuning it n then the next day its screwed up....

 

Yea, it blows.... So ANYONE in the Nashville/Ft. Campbell area that can help a brother out?

 

Do you have tuning software? I'm guessin no by your posts. Maybe time to purchase a tuning suite, and get some assistance through the internet.

 

Im selling my EFI Live if you are interested. I don't know when you will be back home, or if you have anyone who could use it to help your wife.

https://ls1tech.com/forums/showthrea...ht=efi+v1+live

 

Hey man, I can't PM on these computers. Shoot me an email with your price, i may be interested.

zach.forfang@gmail.com

 

With that MAP sensor I used RTV to hold it in place; may want to do it for piece of mind,

 

Already did that. Put a little of the black stuff on there. Seems better but still nowhere near as secure as the stock fitting.

 

If you clean it real good, and put a small bead of "right stuff" on it, around the rubber grommet, and let it cure for 24 hours, you'll need a prybar to get it off.

 

You think that could be the issue? I'd think if it was the MAP Sen. seal leaking that it would have an erratic idle all the time?? No? I'm extremely new in the tuning depo so forgive me if im completely off. You guys are the pro's not me. But im thinking Its gotta be in the tune or how he "set up" the car. I just cant believe the guy let it leave the shop like that. I mean, a "tuner" should know when the car is properly tuned... Then again I suppose its more my fault than his for taking the car in its condition. Let me ask you guys this; Is it normal to drill MORE than ONE hole in the throttle blade? Cuz I think he put like 2 or 3 in that sucker....

 

There is no need to drill at all if you know what you are doing.

Ok, let the drill fans flame away...

 

For ETC cars, I absolutely agree. For cable t-bodies, you def need to drill some of them, as you cant get the blade open far enough without running into TPS problems returning to zero %.

 

You need more air in the throttle creaker table. Less air in the start-up friction table. It is never easy to get a big cam to idle. I will say not the smartest thing I ever heard to put a cam in the car and then give it to the wifey to drive. lol good luck with that.

 

Haha! Trust me brother, she can handle it! No but seriously, she paid for it... She's got full access. I just want this thing to be safe to drive. When she or anyone for that matter is trying to turn in an intersection and the things stalls out every time, its not good.

I was thinking the same thing. Like I said, ive heard of widening the hole, but to drill two more additional holes sounded like a half *** fix to me.... Even if I purchase a tuning suite It really does me no good over here. The Army and its 15 month deployments.....

 

DITTO THAT

I have a large cam in the MS4, ported heads, 90/90, 85/85, big Kooks etc.

My idle is PERFECT a/c on or off; cold or hot driving . . . and without a wideband

It took me a while to GET it perfect though

You need tuning software. No one here can offer anything more than blind, educated guess' without YOU giving US some data on the car

BUT . . . I'll take a guess: drilled holes BAD, idle fueling is off, overspeed/underspeed tables incorrect, low-rpm spark tables are off, and IAC's are WAY out of whack (that last part is crucial).



Christopher

 

Cool guys, thanks for all the help.

 

My vote is to get that MAP secured.
Sort of a hassle to pull the intake, but that sensor is huge, don't want to leave any questions.
It's always either software or hardware, gotta make sure the hardware is solid before tweaking software.

I overdid mine a bit but the bugger isn't moving.

 

That is freaking awesome!! I'll have someone double check the MAP!

Seriously DirtyJohn, thats the coolest thing i've seen in awhile!