I installed a BBK 65MM throttle body today. Now for some reason my idle is 1400 ish. The throttle is fully closing is there a reset that needs to be done on the TPS or computer?

 

Went out and disconnected the battery for a bit and now it's at 1250. One thing I forgot to mention is the throttle seems to lag. When you get off it the rpms hang for a couple seconds than drop off.

 

The latter symptom indicates sticking.

 

I'm going to have to pull the intake tube again and look. I didn't observe any sticking when I tested to make sure it wasn't hitting anything

 

The TSP sensor and idle stop screw on the OEM throttle body are sync'ed.

I dont recommend larger throttle bodies unless you want an extra few HP between 95% and 100% WOT, but you will need a custom program to use it because in open loop the PCM assumes the OEM throttle body is in place and does not add more fuel to account for the extra air a WOT. Closed loop is a different story as MAF can let PCM adjust air and fuel. At WOT.....(OPEN LOOP) the PCM ignores O2 sensors and the MAF I think.......I digress

Here are the BBK instructions....did you do these steps?

From BBK
Set the idle speed by using the following
sequence:
• Turn the ignition switch to the OFF position.
• Turn the throttle plate hard stop screw control 5
turns clockwise from the fully closed position.
• Disconnect the idle speed control solenoid
connector.
• Run the engine until it is at operating
temperature.
• Turn the throttle plate hard stop screw counter
clockwise until the factory idle speed setting is
obtained.
• Increased idle speed may be required if the
engine has been modified.
• Turn the engine off and reconnect the idle
speed control connector.

Turn the ignition switch to the ON position but do not start the engine. Using a digital volt/ohmmeter, measure the voltage between the DG/LG and BK/W wires. Be sure the voltage is between 0.8v and 1.0v. If necessary, elongate the mounting holes on the throttle position sensor to obtain this specification

 

I have the 5 star tunes that take into account the new throttle body and CAI. Later I'll be adding headers and exhaust with retuning to take that change into account as well

I missed the disconnect IAC I will give that try in the morning thanks

 

OOPS!

We have an IAC not a idle speed solenoid.
Turn off all accessories remove negative battery cable from battery and make sure all learned idle is deleted by attaching a wire from disconnected negative battery cable to positive cable on battery. leave that way for 30 min. Or if you feel more comfortable just remove positive and neg battery cables and connect them with out the battery hooked up at all.

Its idling high because the PCM thinks the smaller TB is on there and this bigger one is letting a little more air in than PCM is used to.
I recommend:
https://lib.americanmuscle.com/files/56052-manu.pdf

 

Wondering if just doing the tune would correct it. Or make it worse

 

Tune will not help an idle issue. It will only calibrate for more air at WOT.

The larger TB will add nothing until you hit the cfm of OEM TB, which is about 90% WOT for the BBK.

Did you adjust the idle stop screw?
Do you have a SCT device that will show you what the IAC is doing?

If not download SCT livelink on a computer it's free and will let you see all of your sensors and what they are doing.

https://derivesystems.helpjuice.com/...earch=48465455

I assume 5Star uses sct?

 

Unmetered air getting in was the problem. The plug was missing on the throttle body.

I had adjusted both and the TPS was within spec.

I went with the SCT X4 so I am currently learning all the cool stuff it can do.

Thanks for the help.

 

I'm glad to hear you found the issue.

Let us know how you like the BBK.

 

So far I'm really liking the improved throttle response.

 

Are you running a stock air filter?
Thanks

 

I currently have a K&N drop in filter in the truck. Waiting for the Cold Air Intake setup to arrive from 5Star

 

I am glad that you like your new BBK twin 65mm throttle body, and how it has improved your driving experience. That is what really matters.
I just want to let people know the details on the OEM throttle body which is twin 57mm.

A twin 57mm will flow about 1100 to 1200 cfm (Stock)

A ford V10 at 100% efficiency will suck up 621 CFM at 5200 rpm. Ours probably cant do this because of the restrictions in the stock intake manifold.

413 CID divide by 2 = 206.5 Cubic Inches per Revolution
There are 1728 cubic inches in 1 cubic foot.
206.5 cubic inches per rev DIVIDED by 1728 cubic inches = .1195 Cubic Feet per Revolution of the crankshaft

At 5200 RPM:
.1195 CF per Rev X 5200 Rev per Min = 621.4 CFM

The stock throttle body will flow:
1100 CFM DIVIDED by 621.4 CFM = 1.77
Stock TB will flow 1.77 times the air a V10 could possible suck into itself.
So at WOT the stock unit has the ability to flow about 500 CFM more than the engine is asking for.
Basically the stock throttle body could feed a 700 Cubic Inch Motor.

Please note I have been quite conservative with my flow numbers. The dual 57 mm throttle body is probably closer to 1500 CFM than 1100.