My son decided to put a Throttle Body on my v6 2003 mustang while I was away for the weekend. The only non-stock ad on was a cold air intake I had on it. Well surprise the car runs like crap. I went through all the steps with him to see if he did something wrong but everything looks OK. Do I need to run a diagnostic to get it running right after such an ad on? Any help would be great before I have to run it to a shop.

 

Make sure there are no air leaks at any of the hoses or sealing points. If your check engine light is on, with lean codes, you have an air leak. If your check engine light is not on and the car is running like crap, it should come back on. Check the Cold air intake for leaks as well. You can disconnect the battery for a bit and re-connect to see if the car runs better after at least 20 min of varied driving.

 

As above. I`m assuming it was new? Just the throttle body? No Plenum? If it was a used TB it could have been adjusted for another car. I`ve just put a TB and Plenum on mine. How big was it? Bear in mind the main pipe to the TB itself might be for the standard size TB and if your is upsized its a right pain to get on correctly so there `might` be an issue there.
What about the gasket from TB to plenum? I`m assuming that was added new too? Sometimes the supplied bolts must be used as opposed to the stockers.
Not trying to pick holes in your sons work but was the throttle position sensor damaged during the change or put back correctly?
If no to all of the above bang a code reader on it and go from there.

 

Zigzagg321
The check engine light was on; so I did disconnect the battery and the light went off. After about an hour the light came back on. At this point I did check for leaks but couldn’t find any; doesn’t mean there not there. A friend said I needed to retune the car due to more air coming in. If there aren’t any leaks would that be necessary?

 

Bigkeeko
It was new from American Muscle BBK 65mm Throttle body for 01-04 models. At least he did that right but the car runs like I said on the above post idling high and drivable but with no power at all. The check engine light keeps coming on even after I disconnect the battery. I hate to take it to the shop figured I could fix it with the right direction?

 

can you post pics of it? we could probably see if there is anything wrong

it might be just a line disconnected or something because when i installed my TB i had not problems and it didnt need a tune

 

Found out my TPS sensor was bad; replaced it runs great!!
Thanks guys for the help