Car Stalls after about 45 mins to 1 hr of running

Question

This is a challenge for mechanics. No one seems to know what's going on with my vehicle which is a 2007 Toyota Isis.

If I turn off the car sometime it won't start again and i would need a jump start. Vehicle also stalls after 45 min to 1 hr of non stop driving.

Signs and issues before it stalls

 Right after starting when I am about to move or come out of a corner, it 
 feels like its about to turn off but by pressing continuous gas a puff 
 sound comes from the muffler 

 Rattling in the engine

 Steering Wheel gets tighter (the steering is no longer loose)

 You feel a bubble grinding sound on the floor right before it stalls

After engine cools for about an hour or two car sometimes would restart. If it does not I would need a jump start. I can also jump start it after it cools for at least 15 mins and it runs a little while longer to get me further to my destination. This has been happening for a few months now.

It seemed like an issue with the battery so I started charging it before I start the car "once it has cooled down". I also got the battery tested. The test claimed that the battery was fine but the voltage dropped when I turn on components like the light and AC.

I do not use light and AC during the day so why was I stalling out after about 50 minutes.

Is it the Alternator?? When the negative terminal was taken off the battery the car stayed on??

The car continue starting once the battery was charged but started to drag as it started.

Yesterday the car did not start. I replaced the battery but the car still did not start. I was then told it was the starter "brushes".

It was fixed today and starts right away. I am able to turn the car off and turn the car on with no problems.

Was my issue related to the starter all this time or perhaps there is an issue with the alternator as well.

I know I should have waited until I tested the car performance but wanted to post this now. I plan to test the car driving and performance to see if my stalling issue still exist.

If anyone had the same experience or can shed some additional light I would love a comment....

Answer 1

Probably a catalytic convertor that is defective. The output of the cat maybe partially blocking which might explain the loss of power and the puff sound you hear in the muffler. A damaged cat would make a kind of bubbly grinding sound in the floor as the melted pieces are being jostled about by the exhaust flow. Are they any codes being flagged? Other issues such as an over rich fuel mixture could result in unburnt fuel being sent into a hot cat which then acts as a secondary combustion zone melting the elements inside. Once the output of the cat gets completely blocked the engine will not start at all.

As the for the electrical issues it is probably a side effect of being overtaxed by an engine struggling to remain running under load.

Answer 2

I've had this before when by fuel tank breather was blocked. A car which would start and run fine but after half an hour at motorway speeds, it would die. The roadside fix was the remove the fuel filler cap. Doing this with your ear close to the filler and you'd hear a "whoosh" as air rushed back in to neutralise the vacuum in the fuel tank.

There is a possibility that what you hear prior to the engine shutting off is that fuel pump working hard against the vacuum in the fuel tank.

Answer 3

Maybe check the serpentine belt. Slipping might cause power failure & steering failure unless they're separate belts