I have 95 F150 with 300 inline 6. Smog pump locked up so I bypassed it . Truck ran better than before. A couple of weeks go by and since I've had a small radiator leak all summer and already had pure water in it I tried sodium silicate which seemed to stop my leak. A few hours after this I flushed radiator and refilled with water. Drove truck 2 weeks with no issues and no leaks. Before it was to get close to freezing last weekend I again flushed radiator and filled with 50/50 antifreeze and water. The next morning it was very hard to start truck. It just kept turning over and it finally fired. It runs great after starting and restarts easily until it sits overnight and it again is difficult to start every morning. Some mornings the key on 2 seconds and back off 5 times helps other mornings it doesn't. I can hear fuel pump on and sometimes smell gas when trying to start. I have seen post about possible coolant sensor as well as fuel pump relief valve. I do have multimeter for testing but don't know where either of these are located or test procedures. Any help would be appreciated