Intermittent no start

start
intermittent
pontiac
bonneville

#1

My 1998 Pontiac Bonneville will run fine for a few weeks, then all of a sudden will not start. It cranks healthily, but will not start. If I let it sit for anywhere from a few hours to a few weeks, it starts fine, and will for a few days to a few weeks, then all of a sudden won’t start again. This has been going on for almost a year now. We have changed the fuel pump twice, so we don’t think that that is the problem. Has anyone else had this kind of problem, and what do you recommend?


#2

What happens when it does not start. We need more to work with.


#3

Be sure to respond to Beads question.

Making an assumption about what is happening: Does it do it more when the humidity is high or after it was driven in the rain? How old are the plugs and plug wires? Has anyone checked BOTH ends of any wire connected to the battery?


#4

It cranks healthily, but does not start.
It sounds and feels like it is not getting fuel, which is why the fuel pump was changed.


#5

You need to narrow it down to spark or fuel. Is it associated with rainy or mornings with a lot of dew? If so spark plug wires would be a prime target


#6

Okay, I just found out - when it is going to start there is a noise when you turn the key indicating that the fuel pump is turning on. When it refuses to start you don’t hear that noise when the key is turned.


#7

Humidity has no effect on it.
The battery cable is good (both ends).


#8

It seems to be a fuel problem.


#9

Most cars have a fuel pump relay that controls the operation of the pump. Your description, that you can’t hear it run, describes a faulty relay. Under the hood or on the firewall under the dash is a box containing relays, which should be labeled. Replacing a relay is a simple matter of unplugging the old one and plugging in a new one.


#10

Thank you! I will look for it.
I am told, however, that there are several relays - do you know about that?