ChaoticMunky

Lately my truck has been randomly shutting off while I'm braking. Thankfully it's only happened while on city streets while approaching stop lights. The truck will lunge forward a little bit and then die. Usually only does it once or twice a day and it starts right back up.

It's been doing it ever since I had my truck at the dealer for the airbag clock spring recall and they also threw in a new battery. Any idea what might be causing this?

Truck is a 2004 F-150 4.6L with 87600 miles on it. There's also no check engine light or anything.

screw04

Throttle body needs cleaned and computer needs reset after. Unhook the battery, take out the TB and clean it up. Then afterwards hook it back up and you will be ready to rock

SuzukiRider

My father-in-laws Explorer did the same thing and it was a faulty ignition switch. Not saying thats your issue, but a possibility.

diamonbird

Do a search for your problem on this site......but I think it's the fuel pump relay thingie over the rear axle.

cterry

Mine did that and I went to wal mart and got some injector cleaner and put that in next time I filled up.... It hasn't done it since then so it's worth a try

Mod (Ret.)

Truck starts back up, so I'd rule out the fuel pump module you are refering to.

I'd steer towards cleaning the throttle body plate as already suggested. This has improvved many idle complaints from folks on this forum. It's also the cheapest fix, and will not cost you much if it's the wrong diagnosis, yet improve the idle.

With no codes stored, 87K, and no check engine light, it looks to be your best bet in diagnosis.

Also, has the fuel filter ever been changed? If not, you're way over due.

ChaoticMunky

i'll try fuel injector cleaner first since i'm due for a fill up on gas. the fuel filter hasn't been changed since i've had it, which has been just over a year. the dealer questioned the last time it was changed when they were doing the inspection while doing the recall work. i didn't have them do it because i wasn't about to pay their price for it. if the fuel injector cleaner doesn't do the trick then new fuel filter is next. thanks for all the input!!

cterry

Alright, let me know if it works

Mod (Ret.)

87K on the original fuel filter(?) is way over due. They should be changed by 30K.

Change it, even if it's not the problem.

luckythirteen13

+1, i believe the rule of thumb is 30k miles or 3 years, whatever comes first.

and with 87k on the clock, if the tb has never been cleaned, its going to be way over due. i cleaned mine at 35k and was shocked how dirty it was. just be sure to use the proper cleaner. dont half ***** it either, take the tb completely off and clean it front and back