Stalls when braking

[man of la manche]

I had the front end jacked up for a couple of day while I took the coil springs out to cut then down a bit and now it stalls when I am braking.

 

I can start it and let it run/idle for half an hour and nothing happens, if I drive at a slow speed I am fine when braking, but once I am up around 2nd gear or higher the engine just dies when I brake and it starts right back up, I did a search on "engine stalling" and came up with a few things to check out later today, sensors, fuel pump ballast etc... I am not sure it is the fuel pump as I can rev it high in the driveway take my foot off the gas and nothing happens when I tap the brake, its only a problem when the truck is actually moving and it wasn't a problem before I jacked up the front end.

 

Any other suggestions as to what to look for when I get back at it tonight?

[chicofuentes0224]

My VW used to due that. It was the idle stepper motor. (I think that's what it's called). It's the one next to the TPS. on the throttle body.

[Eagle]

My guess would be a vacuum leak in the brake booster, but I don't see how working on the springs could cause that.

[man of la manche]

My guess would be a vacuum leak in the brake booster, but I don't see how working on the springs could cause that.

 

you never know what is going to come loose, it looked like the p.o. tried to cram springs for a 6 inch lift while only having what seems to be parts for a rough country 4 inch lift up front, when I say I had to jack it up, I really had to jack it up, even with the spring compressors I had to cut part of the bottom coil out of each spring to get them out, so needless to say I think I will give all the lines a once over before I start checking sensors, and I think I will start with the brake booster and then move on to the IAC

 

thanks

[Pete M]

Last time I heard of a similar event it turned out to be a problem in the big vacuum line that runs to the brake booster.

[man of la manche]

checked the brake booster, nothing seemed out of order, however one of the clamps on my fuel filler hose was too rusty to reuse when I put the bed back on and I just forgot about replacing it until today. I got a new clamp and put the vent hose back where it should be on the filler neck, then I turned the key into the on position for a few seconds to let the fuel pump prime and maybe pressurize the tank, it started with no problem and I was able to drive it around the block without the stall returning, I think I will look into a new gas cap this week (it can't hurt)

 

hopefully this was all that was wrong, but I will check the other sensors out on the weekend along with a more thorough inspection of the brake booster vacuum line

 

I already dumped a can of throttle body cleaner down its throat last month, paying close attention to make sure I hit the sensor side of the throttle body, so hopefully that rules out needing to clean the iac, those torx bolts piss me off and I would rather avoid removing them if possible

 

thanks for the suggestions!