Xemeth

No no no no no... Never disconnect the positive and leave the negative. ****ed up battery FTL.

ezerojas

Don't bother with disconnecting the battery. You'll just have to reprogram all your radio presets, the old lady's presets, and your ECU will act all virgin again for a while until it relearns your driving habits. Ford tells you to do this everytime to protect themselves against guys who set the alternator terminal down on a bracket and weld the thing to the bracket or create sparks and set their gasoline soaked rags on fire and file a lawsuit against them saying they were never told to disconnect the battery. In other words, just the fact your read the instructions tells me your smarter and safer than the average bear.

Nice choice on theAccufab tb/plenum, BTW.

RedfireStang03

Does anyone know how long it takes the car toadjust itsltft?

cliffyk

Youshould disconnect the battery to reset the KAM (Keep Alive Memory) any time you modify intake related anything. This will cause the PCM to relearn short and long term fuel trims, idle speed, etc.; it would eventually adapt, however allowing the KAM to clear forces it to learn NOW.[/align][/align]The long term trims are continuously updated, however they do become relatively stabilised after a time--how much time depends on operating conditions such as amount of open/closed loop operation, load, and a number of other factors. It's difficult to pin down and exact duration; 40 minutes to 40 miles probably gets things to 90% of where they will end up...[/align][/align]Oh, as others have said--always disconnect the negative terminal first.. There is no electrical reason for doing so, howeverdisconnecting the negative postmeans that the chassis is no longer "ground" and inadvertantly shorting the positive terminal or other "hot" source to the chassis will not create sparks, blown fuses, et al...[/align]

97targa

You don't have to since there aren'e any power wires to arc. However, with the Accufab T/B it is a good idea for your computer to relearn the idle since it flows much more air. When you do start your car let it idle for 1 minute then turn the A/C on max for 2 minutes and then turn off. This helps your computer learn better. Revving up will do nothing to help.

ezerojas

Lot's more airflow at idle? More airflow in open throttle positions and WOT I can believe, but at idle? Idle flow is governed by the IAC, no?

As for your LTFT and KAM and all that, sure the battery reset will wipe the slate clean, but either way, how soon the computer relearns anything is based on what happens next, battery unplugged or not. In other words, you could clear the KAM, and then not drive it enough or in enough "ideal" conditions that the ECU relearns the trim any sooner. But we are really splitting hairs here.

My suggestion: swap out that plenum and drive the **** out of it, and blow some Chevy tail in the weeds while you're at it.

99GTvert

Some funny replies here.

Do I really need an impact wrench?

Also, I recieved four screws with this, of two diffrent sizes. Is one set for the IAC valve? What about the other, longer screws?

AJ06GT

You're correct, at idle the butterfly valve is completely closed and the air is controlled through the IAC, so a TB and/or plenum swap wouldn't affect idle. It will however affect how much air is delivered to the engine while in the throttle, so I'd still disconnect the battery to reset the computer.

To clarify a little on what everyone is saying, some people are thinking battery is just so there isn't any power to shock yourself or screw something up, but those people are forgetting that disconnecting the battery makes the computer relearn all it's air/fuel ratios and such. When you change anything that affects performance, air supply, or fuel supply on the engine, I'd unhook the battery. It may or may not make very much difference to the computer at all, but it's not hard to reset your clock and radio for a just in case.

As for an impact wrench, you never really NEED an impact wrench, it's just sometimes extremely helpful. I've never changed a TB/plenum on my car, but I can't imagine they are torqued enough to need an impact wrench. Just see what you can do without one, and if you need, get a breaker bar if you don't have an impact wrench, just be careful not to round off the bolts.

Can't help ya with the screws though, like I said, never changed one.