Hi, I have an '89 740 wagon (non-turbo) that won't start due to it flooding the cylinders with gas. If the car sits for a couple weeks, it will run for 20 seconds or so before it floods out. Once it's flooded, it won't run again until it has a chance to dry out.

Code indicated mass air flow or O2 sensor. Sensor is new, swapped out mass air flow and no difference. Tried different ecu. New fuel pressure regulator just installed.

Fuel injectors' ground was checked, and pulse is appropriate. Injectors are all functioning OK. Mechanic pulled plugs and cranked the motor. He said it's pumping too much gas, but that it's not "just pissing it into the cylinders".

I'm sure I'm forgetting something. Timing belt and tensioning pulley are brand new. Recently tuned. Brand new plugs, which have been cleaned a few times now. Compression is fine. Car runs great until it floods out. starts immediately after sitting for weeks, but then dies.

Is there some component in these cars that may have gone haywire, some sort of throttle control or something? I've already spent too much money on this. Up until this point car always started and ran great. It's been pampered with Volvo parts and top notch service. I've got 2 mechanics scratching their heads over this one. Any suggestions would be very much appreciated.

I don't believe it's mechanical, that's been thoroughly checked. I think it's more likely an electronic component somewhere.

If we can't get it going, I'll be looking to sell this car to anyone believing they can get it going or for parts. Still looks very good, loads of new parts I won't list yet. I'd much rather git it going.

Thanks for any help.

Scott