4.6 Grand Marquis LS 98 RPM's

[CARLOS DE LA CRUZ]

Do anyone know why when I put D in my shifter, rpm's slow down a little bit and then recover? I already cleaned the throttle body and IAC and this is the same. Anything that I am missing? Thanks

 

[anderson]

Do anyone know why when I put D in my shifter, rpm's slow down a little bit and then recover? I already cleaned the throttle body and IAC and this is the same. Anything that I am missing? Thanks

seems to me that every fuel injected car in the world does something similar that . you missing nothing as long as its a minor drop. if it just about stalls you have other issues

 

[JavierH19]

That's normal, the torque converter engages and that adds engine load then it accounts for it. Every vehicle i have does that, same with my 2021.

 

[CARLOS DE LA CRUZ]

seems to me that every fuel injected car in the world does something similar that . you missing nothing as long as its a minor drop. if it just about stalls you have other issues

Ok thanks, how many rpm's down is normal? cause it feels like it is going to turn off, but just after that recovers the rpm's

 

[CARLOS DE LA CRUZ]

That's normal, the tq adds engine load then it accounts for it. every vehicle i have does that, same with my 2021.

OK thanks

 

[anderson]

Ok thanks, how many rpm's down is normal? cause it feels like it is going to turn off, but just after that recovers the rpm's

50-150 just a small amount. cleaning the iac never has seemed to work for me id just replace it personally they are cheap for the 4.6

 

[CARLOS DE LA CRUZ]

50-150 just a small amount. cleaning the iac never has seemed to work for me id just replace it personally they are cheap for the 4.6

Ok, thanks.

 

[FastLane]

Totally normal. Dont waste your money parts you dont need. Original Ford parts are better than most junk they sell these days.

 

[CARLOS DE LA CRUZ]

Totally normal. Dont waste your money parts you dont need. Original Ford parts are better than most junk they sell these days.

where I can find original parts?

 

[Lubener]

where I can find original parts?

Look for the Motorcraft brand.

 

[CARLOS DE LA CRUZ]

Look for the Motorcraft brand.

Do you have a recommended website for this?

 

[dnewton3]

Look for the Motorcraft brand.

And also make sure you're not getting counterfeit parts; sadly common from disreputable sources these days.
Get the parts from a dealer, or a good source like ORs, AAP, etc. I find great concern in Amazon and Ebay parts from third party sellers ...
There are several online dealerships that sell/ship stuff. Tasca Ford is one I've used before.

 

[D60]

What year are we talking? Once they went TBW I thought there was no IAC.

If he's TBW then OP should wipe the memory by discharging w a jumper wire and let it relearn throttle trims as he says he cleaned the tb.

 

[CARLOS DE LA CRUZ]

What year are we talking? Once they went TBW I thought there was no IAC.

If he's TBW then OP should wipe the memory by discharging w a jumper wire and let it relearn throttle trims as he says he cleaned the tb.

Grand Marquis LS 98, I just removed the positive of the battery and after 5 minutes I installed again, no problem with that. Or this procedure is required?

 

[Lubener]

Grand Marquis LS 98, I just removed the positive of the battery and after 5 minutes I installed again, no problem with that. Or this procedure is required?

You are taking a chance by removing the positive lead before first removing the negative. If your goal is to reset the computer, you can accompish the same thing by removing the negative lead.

 

[Lubener]

Do you have a recommended website for this?

rockauto.com

 

[CARLOS DE LA CRUZ]

You are taking a chance by removing the positive lead before first removing the negative. If your goal is to reset the computer, you can accompish the same thing by removing the negative lead.

ok, thanks

 

[CARLOS DE LA CRUZ]

rockauto.com

ok, I know this place. Thanks