Another "My car doesn't start" problem

[Richard930]

Was running great yesterday. This morning I hopped in and started it up and it ran for 10 - 15 seconds and then died. Turns over fine though.

Pulled the metering switch wire behind the fuel head, pushed the metering plate down and the pumps are not coming on as they should. Checked the fuel pump fuse and it's fine (cleaned it up just to be sure), replaced the fuel pump relays with known good ones (brand new), as well as the one in the engine compartment (which clicks when I depress the metering plate with the switch hooked up) and still no success. Overboost sensor is hooked up and seems to be fine though I haven't grounded it to be sure.

I kinda find it hard to believe that both fuel pumps would crap out at the same time so I'm thinking its something simpler - anyone got any suggestions for something else to look at? I've searched the sticky but haven't seen anything that looks applicable to this particular problem.

Thanks in advance

[Richard930]

Kept searching and it looks very similar to a problem Mark Houghton had, so I will try jumping the yellow relay to see if that turns the pumps on. On my car the yellow relay isn't yellow - its the same relay as the fuel pump relays up front; been working fine for the last 7 years though.

Even if that works though, I don't really consider that to be a real fix so I'm still looking for suggestions.

[JFairman]

You said you havn't tried grounding the white wire on the overboost switch to see if the pumps run. That's easy and you have to do it to see if the speed relay under the driver seat is good and the overboost sensor works right.

It's a good idea to mount a male spade terminal to a grounded surface nearby the overboost switch so can pull the female spade terminal/whire wire off the overboost sensor and slide it onto it to check things and maybe save a tow charge.

[Richard930]

OK - I'll try that first and then try jumping the "yellow" relay. Luckily the car is in my garage and I've got alternative transportation, so I'm really hoping to solve this one myself with some help from my fellow 930 pelicans to avoid any towing / shop charges.

[Richard930]

Solved! Grounded the overboost sensor and she fired right up, so I guess its time for a replacement.

Thanks to everyone who has contributed to this forum for helping me save tons of dough on maintenance & towing costs (which gets to be spent on fun stuff like turbo, headers, muffler, etc..)!