car dies when I hit the breaks

[VSOphof]

I own a 95 lesabre and for the past few monthes, when i hit the breaks the motor with just die. Does not do it every time. All the electrical will still be on but the motor will just die. If I put it in to netural and turn the key, it will start back up. Luckly I have not been in a wrek because of this as of yet. But I was almost in one when it died as I was going around a sharp turn. Any ideas to why this is happening? It only happens when I hit the breaks.

[maxwedge]

Welcome to AF. I'd clean the throttle body and remove the iac and clean the unit and passages also, throttle body cleaner is used here.. Then go from there, see how it is .

[Bassasasin]

Just from what you have said its likely your engine is having trouble with the idle at low rpms.

No real expert here but idle issues are cleanliness, injector efficiency, sensor readings, air flow (filters, etc)

Could go into ignition but you say it runs well above 1200 rpm so for now, not thinking there.

It wouldnt hurt to get the codes checked for free at a parts store.


I had a 94' that randomly quit at different speeds.... turned out to be a CRANKshaft sensor.. was somewhat tough to troubleshoot.

Good Luck

[VSOphof]

My check engin light does come on from time to time but never stays on. I have a code scanner for this car, but always the same problem. Link Error. My 95 lesabre has the OBD II link conector on it but I think that it is wired differently from the standard becaue I have used my code scanner on other OBD II cars and it works fine. Also, if it was something having to do with the throttle body would it not idle a bit ruff when just sitting still or at real low speeds? I have no problems in that area. It never dies when I let off the gas, only when I apply the break. Could a short in the elctrical for the breaks cause the motor to die?

[Bassasasin]

This is mysterious.

Does it stall in the driveway when you hit the brakes?
Is it stalling after driving it and its warmed up and you just came from a higher speed?
Im thinking of the vacuum is pulling it a bit down possibly a vacuum leak.

To determine if its electrical you may need to try disconnecting the brakes electrical such as brake lights fuse, or ABS, one at a time.


Good Luck

[HotZ28]

This is very rare, but I have seen a leaking diaphragm in the brake booster cause this kind of problem. It usually is not a problem until you hit the brakes! Also check the check valve at the booster and vacuum hose. Electrical problems are not likely to be the problem here!

[VSOphof]

It only stalls when comming down from a higher speed. I will try pulling fuses and see if that does anything, but this is a problem that only happens every now and then. I don't know if this is related but I do have a strange problem that causes my ABS light to come on. When I try to roll down the passenger rear window with the switch on the drivers door sometimes it will cause my battery gauge to drop while my ABS light comes on. It only happens when that window is rolled down from the drivers door. Again, this is a problem that does not happen all the time. Do you think these two problems are related?

[Bassasasin]

My

There are possibilities you do have a system voltage/current problem.. or even a possibility your TPS is irratic at that range.

If your alternator is not producing enough current when the engine speed drops down it then draws from your battery. If the battery circuit is poor the voltage continues to fall below a devices functional range and all possibilities can happen.

I would think your system could be tested with all electrical turned on possible such as headlights, heater blower, and then try to roll all windows down at the same time while watching a voltmeter.

It could be something as simple as a loose connection or a bad alternator or loose belt or even the belt tensioner.

See if you can try watching the voltage under a load with a Digital volt meter.


Good Luck

[VSOphof]

Alright, thanks for the info. I will test those things this weekend and let you know what I find out. With anyluck it will be something simple. Thanks again.

[VSOphof]

Here is the up date, I cleaned the throttle body and the problem with the car dying was fixed. But I have another problem. While I am in the gas my car vibrates. I notice it most around 50 mph. It completely goes away when I give it full throttle or when I completly let off of the gas. But when I am driving normaly ( regeular accerlation or steady speed) it vibrates. I notice it between 35 and 80, but like I said, it is most noticeable around 50mph. Any ideas????

[Bassasasin]

I sugest you start another post.. it gets better attention.. and beter forum ettiqette.


Bass