Hey all,

I have another small thread going related to my issues with stalling in my 02 X Type 3.0. The car stalls rather intermittently at various points from highway speed to sitting at red lights. Sometimes it can happen twice in a day, other times I can go for 2 weeks without incident. I had the car in with my local mechanic who could not replicate the problem. He believes it is some type of electrical issue, but has not tested it in the manner that Thermo recommends.

Today, after reading some threads I decided to check out the Inertia Switch and sure enough it clicked when I pressed it. The car seemed to run fine, but who knows what caused it to trip and why it ran after doing so.

One thing that I do notice is the lack of a sound from the fuel pump when this issue arises. When trying to restart the car I listen for the fuel pump to kick on. It can take 3 or 4 attempts when the problem occurs and I finally know it will start upon hearing the pump when turning the key to "on."

Sorry about the rant, but I am trying to figure out what to do or who to take the car to next (hopefully not the dealer). Any insight would be greatly appreciated.

 

Also, I have codes P1646 and P1647 pertaining to o2 sensors.

 

Kev, it is possible that with hitting bumps and whatnot, that if the inertia switch is a little loose, it will work its way to the open condition. In your case, it was right on the edge of opening and simply wasn't making good contact. The ultimate solution is getting a new inertia switch and replacing the switch. Shouldn't be too expensive. Looking online, the MSRP for the new switch is $21.29. So, if you have a few bucks, I would swap out the switch and go from there.

 

Thermo, another thing that I've noticed the last few cool mornings is a hesitation, almost stalling nature after getting into gear after initial start up. The car starts fine and sounds normal. I put it in reverse and back out, then to drive and that's when it runs rough momentarily. Once I get going it runs fine. This is different than the other stalling problem which was more of just an engine shut off. Do you think the problems are related or could the rough start be due to the two 02 sensor codes being thrown?

 

Kev, based on what you are describing, I am thinking that the stalling and the hesitation is a related item. It can be something as simple as the fuse is starting to go and it is making intermittent/weak connections, leading to a reduced voltage at the fuel pump (leading to the fuel pressure to the motor being a little low) or the inertia switch is making intermittent contact which is making the ECU think the car has been hit and therefore shutting off the fuel pump, etc.

 

Kev, when you have the stalling problem, does the instrument cluster remain fully powered up or does it start to dim at all? The inertia switch takes out a lot of things in the car. So, if the inertia switch would be the issue, you would be seeing a lot of things going south. Things like your wipers, power windows, all the electronics associated with the engine, external lighting of your car (specifically the tail lights and rear turn signals), steering system controls, power mirrors, alternator charging circuit (your battery light would most likely come on), and you A/C system would act funny. So, as you can see, you can somewhat eliminate the inertia switch if these systems are acting normal when the engine decides to die. It is an all or none thing as there is a single wire running into and out of the inertia switch.

 

Thermo, when the car stalls the dash typically does not change. The oil and battery light come on in the exact manner as turning the key to the "on" position. I don't recall it ever stalling at night, so it's had for me to say if lights are dimming and such. As far as other quirky things, the sunroof one touch feature stopped working a couple months ago. I fixed it the night that it happened, and it's been fine since.

 

Kev, from the sounds of things, you have a problem with the fuel pump or the wiring associated with the fuel pump. As for which way you want to jump, that is going to be something you will have to take a leap of faith and go from there.

 

I know you may not do this. But check the alcohol content of the fuel. Anything around 20% will cause what you describing. Especially at start up, but also while driving. Anything about 10% is too high.

 

Were is the inertia switch located???
Eric