1996 GMC w/ 305 cold start prob.
Question:
Turns out the fuel pump was going bad.
Response:
Could be that one of your temperature sensors – manifold air or coolant temperature – is going out, and giving incorrect readings.. — Robert Hancock Saskatoon, SK, Canada NEW Home Page: http://members.home.net/hancockr
– Hide quoted text — Show quoted text -> Hello, > I thought I would throw this out there before I take my truck in (to get an > idea of what to expect). Lately, the truck is taking longer and longer to > start when cold. It used to be that the thing would fire immediately when > turned over, cold or hot. Now, it is taking longer and longer to start when > cold. The strange thing is that the "longer and longer" is like clockwork. > It takes probably 2 seconds longer to start it, each time I start the thing > cold. I’m to the point now where it takes more than one turn of the key to > fire up. At least I know exactly when its going to start (2 seconds longer > than the last time!). > Thanks, > Jason
Response:
Hello, I thought I would throw this out there before I take my truck in (to get an idea of what to expect). Lately, the truck is taking longer and longer to start when cold. It used to be that the thing would fire immediately when turned over, cold or hot. Now, it is taking longer and longer to start when cold. The strange thing is that the "longer and longer" is like clockwork. It takes probably 2 seconds longer to start it, each time I start the thing cold. I’m to the point now where it takes more than one turn of the key to fire up. At least I know exactly when its going to start (2 seconds longer than the last time!). Thanks, Jason
Response:
Jason, Here’s a thought. I recently read that a lot of the GM fuel injection systems route a second path for fuel pump power through the oil presure switch. If the fuel pump relay fails the pump will still run once oil presure comes up. That explains a longer crank period, but probably not a 2 second add on every day, unless your weather is rapidly warming up. Just a thought. Bruce Prigge, North Branch Mn – Hide quoted text — Show quoted text – > Hello, > I thought I would throw this out there before I take my truck in (to get an > idea of what to expect). Lately, the truck is taking longer and longer to > start when cold. It used to be that the thing would fire immediately when > turned over, cold or hot. Now, it is taking longer and longer to start when > cold. The strange thing is that the "longer and longer" is like clockwork. > It takes probably 2 seconds longer to start it, each time I start the thing > cold. I’m to the point now where it takes more than one turn of the key to > fire up. At least I know exactly when its going to start (2 seconds longer > than the last time!). > Thanks, > Jason
Response:
Makes sense, but wouldn’t the behavior be the same hot and cold in this case? Mine is only when cold… – Hide quoted text — Show quoted text – >Jason, >Here’s a thought. I recently read that a lot of the GM fuel injection systems >route a >second path for fuel pump power through the oil presure switch. If the fuel >pump relay >fails the pump will still run once oil presure comes up. That explains a longer >crank >period, but probably not a 2 second add on every day, unless your weather is >rapidly warming up. Just a thought. >Bruce Prigge, North Branch Mn
