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Amedee, Former ASE Master Tech
Category: Car
Satisfied Customers: 24128
Experience:  ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector
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Hi, can a clogged catalytic converter cause the engine to hesitate

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Hi, can a clogged catalytic converter cause the engine to hesitate or shut off completely?



A clogged converter can cause a extreme loss of power. However, the engine should still be able to idle.

Customer: replied 8 years ago.
So where else should I begin looking such as electrical components, grounds? I already know the catalytic converter is bad but the vehicle has twice completely shut down. Once due to the fuel pump burning up but the last time it restarted after sitting a few days on the first turn of the key.
DOes it crank over?
Customer: replied 8 years ago.
Yes, it's running right now. After driving say for about five minutes or so I'll notice it cutting in and out causing it to lerch while driving down the road. The last time it did this it eventually lost so much power that even with me on the gas, it just stalled out and could not be restarted. After it sat for a few days it again cranked right over.

Ok, when it does this, we will have to figure out what the engine is missing so we can pinpoint the problem.






All three of these are tested when the engine is being cranked over. There are two way of checking for fuel. Fuel pressure and fuel trigger. Both are very important and must be present for the car to start. Fuel pressure is self explanatory. You just hook up the gage and see what the reading is. Fuel trigger is check with a noid light. The injector gets unplugged and the noid light gets plugged in to the injector clip. With the engine cranking over, this light must blink. This is the signal to the injectors from the computer. You can have all the fuel pressure in the world, but it wont matter if the injector is not pulsing gas into the cylinder like it should! Compression tester, spark tester, fuel pressure gage and noid light are all accessible at your local auto store. All three tests play a very important part in diagnosing a no start condition. Be extremely careful when doing these tests.


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