Rarely starts when it does it shuts off then it starts

JASON FERNANDES

MEMBER
1992 PONTIAC GRAND AM
3.3L
V6
2WD
AUTOMATIC
107,678 MILES

A few hours later it will not start. I ran the odb codes. 13, 31, 34 and 42. O2 sensor, MAF sensor, ignition control module and PNP switch. I replaced o2 sensor, MAF sensor and the ignition control module. But I'm still getting codes for the o2 sensor and ICM. I didn't replace the PNP switch so that's also coming up. What the heck is going on. I mean it does start from time to time. I can hear the fuel pump running. When it does run there is no misfires happening. So I tend to believe there is spark and fuel getting to the engine. Does anybody have suggestions?

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,755 POSTS

Hi,

To help narrow down possible causes, here is what I need you to do. When it won't start, check to see if there is spark and fuel to the engine. Chances are there will be one missing. Once we determine that, we will have a focus.

Here are three links you may find of interest. The first is how to repair a crank no start condition. The next two explain how to check for spark and fuel pressure.

https://www.2carpros.com/articles/car-cranks-but-wont-start

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/how-to-test-an-ignition-system

The easiest thing to do if you would rather not to the tests above is simply see if it starts for a couple seconds when using starting fluid. If it starts for a couple seconds and then stalls, we have a fuel related issue. If it doesn't even try to start, then it's ignition related. Most likely, the crankshaft position sensor.

Take a look through this link and see if it seems to mirror what you experience.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

The crankshaft position sensor in at the front of the engine near the crank pulley. I suspect we will find it is either that or the digital electronic ignition. I attached a pic below and circled both.

Let me know what you find. I will watch for your reply.

Joe

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