94 Buick PA - Braking & Electrical

Hello to all Automotive Masters

I have a 94 Buick PA with 132000 miles. I purchased it in Nov. 2005 and the only thing major I had to do was a tune up. I've driven it from Houston, TX to Phoenix, AZ and change the fuel filter regularly. I just purchased a new battery from Walmart and changed out the entire positive wire and cut off most of the corroded negative wire and coupled it with fresh new wire. The issue is, most of the time while I'm in transit (in motion) and in moving traffic, when I step on the brake pedal , the car shuts off and immediately comes on again. When I'm at speeds of 50-70 mph it does the same thing, but it comes back on immediately. Now it doesn't happen all the time, if I gently step on the brake pedal, but it happens when I step on it in the normal way. I've had the battery and alternator checked by AutoZone and everything is still good. I haven't changed the alternator since I've had the car, and they said it was still a good alternator. No loose wiring and the connections on the battery are sealed. I was thinking of having a diagnostic test done but I want to check with you guys first b4 spending the money if it's not necessary. You guys have steered me well and right every time in the past and I thank you. Please help.

SOS

WWHZD? (What would Hot Z do?) First off, when you say the car "shuts down", do you mean the engine, or does everything shut down like you just pulled the key out of the ignition? This will help in finding where to start looking for the problem.

Thanks Hot Z.

U R correct. It's like I've taken the key out of the ignition and the car is completely off, everything, but it comes right back on. The time that it's off is about a half a sec to a second. It happens so fast but it's noticeable if the music is playing and the ac is blowing. U can feel the sudden lost of power leave and then instantly return. If I'm rolling I never have to come to a complete stop when it happens because it happens so fast. It's like flicking the light switch off and on, off then on, or on then off.

Sorry, the other poster was not me; however, you should check the battery cables for corrosion, then clean, lubricate & tighten them. Side post terminals are notorious for causing this sort of problem.

Thanks HotZ28, and bradybsw,

yesterday it completely stopped and shut down on me. it appeared that it was having a electrical meltdown at the time. all the lights and warnings on the dash was going crazy. then i waited a few minutes and it stopped. i tried to start it and it came on but it was sluggish, and then it stopped. after that it didn't start again. it would crank (turned over, when I turn the key in the ignition) but it wouldn't start. i checked the battery's acid department and it was low in all six holes, so i put a little water in it. turned the key in the ignition, it crank or turned over, but no start. i figure, it has 132,000 miles on it, i haven't had any major repairs on it since 80,000 miles, it must be the timing. well i had it towed to the nearest AAA auto shop and learned that it's the fuel pump and fuel system. the repairman quoted me $1,300. HotZ28, is that reasonable or can it be done by a novice as myself? I've done a few minor things on the car like changing the battery, alternator, fuel filter, fuses, etc, but is this changing the fuel pump a thing for a mechanic? the car is currently at the shop and i've stop them from dropping the tank. awaiting your reply.

Many thanks.

Did they check the fuse & relay, or if the pump is running, test the fuel pressure to determine that the fuel pump was bad, or was that just a "best guess" estimate? I know you are in a tight spot without a way to move the car and the villains at the shop know that, but $1300 for just a fuel pump, is outrageous! If I were you, I would do some shopping around and get some other opinions from some reputable shops. If you have basic mechanical skills & tools to do the job, you can do it, it's not that bad. We have plenty of threads in the PA or LeSabre forums with some detailed instructions on the procedure, do a search. Did you check the battery cables & battery under load? What is the battery voltage? Can you here the fuel pump run for 2-sec when you turn the ignition on? Personally, without being on-site, I think you have electrical problems! If the fuel pump is not running, that could be a result of the electrical problems and not the only issue. Do some more research and let us know what you find. Good Luck!

I agree with Hot-Z. It sounds like you have other electrical problems that may also be causing the fuel pump to act up. The problems you describe would not be the result of a bad fuel pump. If you have already checked your battery cables, check the fuses and relays for corrosion or loose wires. Like Hot-Z said, its hard to help with this one with out being on site. :banghead:

It is possibe that one of the posts (positive or negative) in the battery is bad. I had a fairly new battery which went bad because the positive post inside the battery broke off from whatever it was connected internally. I could tell be wiggling the positive terminal - it was loose.