Car dies while braking

Updated from previous thread where car would just die out once I started driving…I used to start the car, and it would idle high and fluxuate idle, and once I started driving the car would die about a block away. Fast forward to now (almost 2 months later).

So the car is ALMOST done. The engine was missing the PCV valve, and a few other vaccum lines. Set the timing correctly, tightened the timing belt, new plugs, wires, and bled the cooling system. Also got the idle to steady out (I’m sure it was the vaccum lines and PCV valve) at 900rpms.

BUT, there is one small lingering issue. The car stalls ONLY WHEN BRAKING now. If I sit at idle and press the brakes, the rpms dip from 900 to about 600. When braking while driving though, as soon as I get to a stop, the car dips too low and dies. It fires right back up and I can continue driving.

So the issue of it just dying while driving is now gone…now it just dies while coming to a stop. I thought the brakes being applied should raise the rpms, no? Like when sitting at idle and you press the brakes, shouldn’t the rpms go up 2-300rpms, then level out again?

So progress is being made, it’s just this last final hurdle.

Could it be a bad brake booster? Or a vacuum leak in the braking system? what about maybe a bad brake booster check valve?

It basically does this EXACT thing.

http://www.youtube.com/watch?v=08ueD7vvWsQ&feature=youtu.be

If I dance from throttle to brake while braking, I can keep the car running.

There is another thread about the lights dimming and radio cutting out and also weird idle. I posted to that thread about that it could be a ground because I had a similar issue with the radio cutting out when I hit the brakes. I narrowed it down to being a corroded negative terminal on my battery. It seemed like the brakes lights used up too much energy to light up and it would cut out my radio for a split second and my rpms would act up. It might not even be close to your problem but it’s worth a shot to check all your grounds.

Already removed, cleaned, and tightened all grounds. I don’t lose power when this happens. The motor just dips too low and dies.

Make sure your injectors are not leaking any fuel. I THINK this was my problem (although still not sure, as I’ve done a lot of other things in the meantime). Also might want to check fuel pressure and make sure it’s within spec

fuel pressure should be fine if the car is running shuts off n starts right back up…a leaky fuel injector would not cause the car to shut off… it sounds like when you brake there is alot of voltage being used …i would get the alternator tested at a shop usually they do it for free…check your brake booster vaccum line as well

Yeah tonight I’ll be testing the brake booster using my Helms. I’ll report back.

I don’t think it has anything to do with electrical, I’m almost certain it’s fuel delivery related… I forgot to mention that I replaced my fuel pump too, it got to the point where it was priming, but just with no pressure. What would be ideal would be to buy a fuel pressure gauge (B&M makes one), and somehow record the gauge while braking, this would rule out or verify my fuel related hypothesis.

check your engine vacuum.
the booster pulls vacuum from the engine. if vac is low already, the booster will kill it.
the brake lights do draw a lot of current. to cancel out an electrical issue, remove the brake light bulbs. see if it changes things

[QUOTE=welfare;2253392]check your engine vacuum.
the booster pulls vacuum from the engine. if vac is low already, the booster will kill it.
the brake lights do draw a lot of current. to cancel out an electrical issue, remove the brake light bulbs. see if it changes things[/QUOTE]

I’ll try that. I’ll just remove the fuse.

Just want to update this. I ordered a Walbro 255 pump, dropped it in, adjusted the idle, and have had ZERO issues since. She idles great, doesn’t dip, and runs like brand new!!! So fucking happy!

i know this is an old thread but having the same problems too. how hard was it to swap out that Walbro fuel pump?

the walbro is a direct fit repacement.

to do the swap you will ave to pull out the lower back seat cushion to get to the access port at the top of the fuel tank.

i just read on another forum that 2nd gens need to drop the tank. is this correct or can i do it from the inside?

drop tank, yes. the access hole is for the sender only. not the pump