I'm sure that this topic has gone around more than once, but I had trouble finding a post on point in the archives so thought I had better check. The car is an 83 240 turbo, that started showing some symptoms of fuel check valve failure on cold starts, but not consistent at first. Some mornings it would do it and some it wouldn't. Over the last month or so, the initial priming of the main fuel pump also started getting sporadic; i.e., no buzzing from the pump. And it stalled once at a traffic light. I checked the fuel pump fuse (#7) (it was OK) and replaced the fuel pump relay. The new fuel pump relay seemed to improve things a little when first replaced. Now, there is no response from the fuel pump when the key is turned to the aux position, and it takes 3 cranks to get the engine going without stalling. Voltage at the fuel pump: about 10.9 V. I'm wondering if fuel pump problems might cause a partial relay failure. Whether I need to replace the pump, not just the check valve.