jimmypop13

iTrader: (17)

My car seems to be doing this at random. It doesn't really do it when I first start to drive on a cold start but after a few minutes, the rpms will hang around 1200-1300rpm when I clutch in at any speed, until i've finally come to a stop. Then after that starts, it's all completely random when the rpms will hang like this or will drop closer to idle like they should. Occasionally the rpms will stay much higher(1800rpm) and occasionally the rpms will drop way too fast and almost kill the car. It's like the IAC has three modes to choose from after it warms up, open too much, just right, closed too much. I tried to show Patrick G the other day what was goin on but it acted perfectly normal when he was in the car. I installed a brand new Delphi IAC sensor since I thought that was the problem but apparently it wasn't.
It's just driving me crazy and I'm not sure if there's something hidden in the tune causing this that needs to be changed (another shop had tuned it first), or if I have some bad wiring or if I need a new ECU. I did notice the bottom ECU connector must have had some water get in there at some point bc when I pulled the connector, there was white residue all over the pins and the floor around them.
Has anyone ever experienced anything funky like this at all? It's like there's a grimlin in the car somewhere. I just don't have a clue where to go from here!

SSpdDmon

iTrader: (10)

It sounds to me like you need to do the RAFIG process again. If that was done correctly, I would then look to your idle learning being too aggressive. If it was throttle follower or throttle cracker, it would do it rather consistently. However, it seems the learning is over-correcting your base running (desired idle) airflow.

PoorMan

I had this problem after my M6 swap. If you take the load off (clutch) the throttle body needs to close some to keep the idle constant. You need to lower your IAC settings when the clutch is in. Requires playing with it since having a cam, heads, and all that will make everyone unique. I have an LT1 so the table is labled different than yours I bet.

JD

jimmypop13

iTrader: (17)

i understand that and the table is adjusted, but what I'm saying is randomly instead of performing like it's tuned to, it will do it's own thing and rev higher or close too fast. Something is keeping it from always working right and it sounds like SSpdDmon may be on to something.

jimmypop13

iTrader: (17)

driving through my neighborhood today, the rpms were holding at about 1300rpm. It's just frustrating bc it makes it harder to shift smoothly unless I slip the clutch quite a bit.
Turning out of the neighborhood, I floored it in first and a little in second gear and after that, when I would clutch in, the car would almost die and then catch itself and stay right around idle which is 850rpm. I'd much rather have that than the hanging. I wonder if flooring it caused something to change. Could traction control have anything to do with it because I turned it off right before hand.
I also had my AIR system removed at a shop, I wonder if there could be some small vaccuum leak doing something somewhere.

SSpdDmon

iTrader: (10)

AIR is completely down stream. So, it would cause an exhaust leak...not a vacuum leak. TCS has nothing to do with it either.

jimmypop13

iTrader: (17)

ugh!!

TAQuickness

iTrader: (28)

Sounds like your throttle cracker table is off. Sometimes when you let off, it goes right back to idle (these areas of the TC table are correct), but other times you let off it hangs (too much air in these areas of the TC table), and other times the car wants to stumble (not enough air in these areas of the TC table).

jimmypop13

iTrader: (17)

Anyone care to loan me $1.5k so I can get EFI Live/wideband/roadrunner???

oh well, I'll get it one day. Thanks for the help

SSpdDmon

iTrader: (10)

Roadrunner is a nice to have. Don't get me wrong, I'd really like to have one. But, my car drives great and I didn't do anything real-time.

If you're just starting out with driveability tuning, you don't need a WB right away.

So, all you need is V1 and a laptop. If you already have the laptop, then you're talking $500 or so. Get to know the software while saving for the WB. That's how I did it originally.

zapp168

iTrader: (7)

RAFIG?
Back to lurking

zapp168

iTrader: (7)

Ok Ok......do a search....read the stickys....I know I know...... That was the easiest search ever.....

SSpdDmon

iTrader: (10)

Yes! Finally! Someone did it right!

stepuptata

iTrader: (11)

my car has an idle issue like this. My car likes to hang around 2000rpm.(at times) I have to rev it up or down shift to get the rpms to drop. It also idles high @ 1100-1200 rpm. My car is a 383 cartek stroker and tuned by them. cam 230-234/.600@113lsa. I bough the car this way and I live no where close to cartek. What is the easiest software to learn as a beginner. I'm not very good at computers what so ever. Would like to start learning how to tune my car. Thanks.

81LS1Camaro

iTrader: (1)

I have the same problem

SSpdDmon

iTrader: (10)

It's never as easy as it should be. The easier software to learn depends on what you like. Personally, I liked EFI Live because the interface works very similar to Windows Explorer (folders to drill down into on the left - view of the tables on the right).

If you're not the type of person who knows their way around the computer, I wouldn't advise getting a piece of software like EFI Live or HPT unless you accept the fact that it's going to be a longer term commitment. I've been doing this for 2 years and feel relatively comfortable with tuning. But, there's still quite a bit I'll admit I don't know.