2000 Pontiac Bonneville stalls and hard start

Is the check engine light on? Have you checked fuel pump pressure? Also, do volts drop before it dies or while or after?

There is no check engine light on. We have not checked the fuel pressure and the voltage drops before the vehicle stalls.

If the voltage drops before the engine, it sounds like it is related to the electrical system, but that could also include an electric fuel pump that is bad. What I need you to do is when this happens, check fuel pump pressure to make sure it is working properly. Here are directions for checking it:

https://www.2carpros.com/how_to/how_to_check_fuel_pressure.htm

You will need a fuel pressure gauge. Most parts stores will lend or rent them to you.

Let me know what you find.

Joe

attached fuel gauge showing 39 psi. took off vacuum line registers 48.

Then it has to be an electrical issue. My only thoughts at this point is a bad fuseable link between the lat and battery.

Thank you for all your help. I guess its time to take it to a mechanic's shop. Any idea how much this will cost. Thanks again.

I have to be honest, it's hard to estimate how long they will take to track it down. As I mentioned, I feel it is related to a fuseable link. When you take the vehicle, tell them the battery and alt are good. You had them checked. As a result, you feel it is related to a fuseable link.

Hopefully, they will start there and it won't take as long.

Let me know what you find.

Joe

one last question, you said it might be a fusible link between the lat and battery. what is the lat?

I'm sorry... typing too fast... lat is actually alt.

Here's an update on my car. Took it to a mechanic. They said they could not locate what was wrong with it, but they did find 2 fuel leaks and they fixed them. Cost 130.00. So my son had a code reader and it read that there was a problem with the catalytic converter. Had that repair by another place which cost 238.00. Now code reader is giving us a code of po336. Crankshaft sensor is new.

There is a chance you got a bad one. Check this page out and follow the steps in checking it to see if that is actually the problem.

http://www.adriatic-company.it/matizclub/tecnica/manualeII/M31f3%20Engine%20Controls%20152-279.pdf

The PO336 is the first code and provides step by step instructions on how to check the system for that code. Let me know what you find.

Joe