I've been dealing with this problem for a month or so now and it seems to be getting worse. The car starts fine in the mornings and on cool days. If it's been sitting in the hot sun, or I've driven it somewhere, shut it off, then tried to start it again is when the problem occurs. A couple of times it's died while driving down the highway and takes multiple attempts to restart. Here's what I've diagnosed so far:

1) The fuel pump works fine and kicks on every time.
2) I've pulled the code and get 9 longs flashes indicating the "No 1 Cyl Position Sensor" according to Troublecodes.net
3) I performed the ignition switch test with the following results
3a) The car stays running if I slowly move the key to start while the engine is running
3b) I get a buzzing noise from beneath the dash just before the starter is engaged while the engine is running and key is being turned
3c) If the key is slowly turned VERY slightly toward the off position with the engine running the car will die
3d) With the engine off and the key in the on position I can make all the dash lights flicker by wiggling the key

I know the above seems like I've pinpointed the problem to the ignition switch, but I want some good SOUND advice before I start replacing parts.

Thanks!!!
-rob

 

Problem has earmarks of Main Fuel Relay, but you say the fuel pump always comes on.

To be sure it's the ignition keyswitch assembly, you should notice whether the CEL and Alt light come on when car won't start. If not, the ignition switch is likely. Another method is to rig a small 12v tell-tale light to the Blk/Yel wire at the distributor and bring light into the cab where you can see light every time you attempt to start. If light is not on w/ keyswitch in On or Start positions, then ignition switch is at fault.

The ignition switch is easy to replace and costs < $50.

good luck

 

Where does the ambient temperature come in as a factor? The car starts every time but dies instantly and all the lights are operating.

 

If the inside of your car is very hot, it can cause the main fuel relay to stop working properly. Its a common problem with bad solder joints on the MFR's board.

The temperature in your car may also affect bad contacts in your ignition switch, but not to the same extent as the MFR.

It really sounds like you will have to replace the electrical portion of your ignition switch. Key shaking/position + flashing dash lights/stalling = bad ignition switch IMO.

 

Those 2 items sound like a bad ignition switch. Sounds like the engine switches OFF a little too close to the ON position. Does that happen in a very consistant position?

Maybe if you look at how the electrical part of the switch is mounted, it can be adjusted slightly? Or maybe it's just loose?

 

I'm almost certain it's the ignition switch now...

Today I didn't let the key return to the on position on its own but would slowly release it after the car was started. It stayed running every time.

 

That's a CLASSIC symptom of a bad switch.