My f150 4.6 wants to die when put in reverse, I changed plugs, fuel fliter, and one coil pack with a used one. The tac is really low when put in gear, otherwise idles just fine any ideas.? Thanks

 

Clean or replace your Idle air control.

 

Hey I did try to clean it but it did not help. I looked at buying a new one but they want 120.00 for it. What if it not the idle, but maybe the throttle control?

 

I've used the autozone one in both my trucks with no issues. That part is about $45 it most likely is the IAC

 

hey thanks ill just have to try a different auto store. Live in a small town with no parts stores.

 

you could order it online. I'm sure rock auto has them cheap. They have shipped quick when I've ordered from them.

 

Hey thanks again. I checked online and there is an auto zone about an hour away. It is about 47.00 so i think i will try it. Thanks.

 

Ok now 50.00 bucks later and still same results. Truck die when put in reverse and drive if it warm then it just idles really low and has no power. Maybe fuel pump or throttle control? Anybody had the same problems.

 

I had the same problem last winter. When I put the transmission in reverse the pickup would either die or idle real low. I had just had a transmission fluid flush and change. It turned out my new tranny fluid filter was loose, put in a new one and the problem quit.

Good luck,
Shawn

 

Check for vacuum leaks. Look at the pvc elbow at the back of the throttle body. Make sure its not leaking.

 

Did the check engine light come on? If so, go back to Autozone and get the codes read.

 

No the check engine did not come on. I see no vacuum leaks but will check again. Thanks everyone.

 

Well another day and more money spent trying to find the problem. I had it checked and found out my check engine light does not work but it was codeing o2 sensor, so i put a new one in and it does seem better it does not die now but kind of sputters then kicks in when driving, maybe it fouled a plug or it does need wires?

 

Did you disconnect the battery and turn the lights on to reboot the computer after all this. if not you should do that.

 

Ok. When I put the new o2 in it I did the battery. Had it coded again today and number 6 plug misfire so I checked that out and it had a lot of water in it. We had some big snow drifts last week. So I'am putting new plugs in later tonight and see what that does. Thanks for your help. It is getting better slowly.