Engine Performance problem
1998 Chevy Truck V8 Two Wheel Drive Automatic 110000 miles
Saturday my truck wouldn't start, I had good battery, spark, and thought fuel pump was out.I couldn't hear pump buzzing when turning key to on, but could feel relay clicking when turning on key. Would rotate, rotate, not turn over. Same thing on Sunday when trying to start truck. This morning truck starts up fine, first turn of key, I drive her around, come home, turn off, starts up. Wait till engine cools down, try again, starts right up. And I can hear the fuel pump buzzing now(priming) the fuel pump is 2 yrs old, replaced 2006. Anyways, I have no idea what caused truck not want to start. Anybody got any ideas?
Test the coolant temperature sensor and the fuel pressure-
May, 15, 2008 AT 5:24 AM
When you changed the fuel pump in 06 did you change the fuel pump chassy wiring harness connector?
Do you have a PASSLOCK system on your truck? PASSLOCK is a factory passive security feature--If you have it there will be a security light that lights up breifly when you turn the key.
May, 15, 2008 AT 8:51 AM
I had a shop replace the pump in 06. I'm guessing the pump came with a wiring harness? And hoping they would have replaced it. They charged me 464$ for pump I think it was. I have an aftermarket security system installed(prestige) with a starter kill on it, but I rarely ever arm it since i've moved to the burbs and park in the garage. I've had a couple of people tell me I could have a bad female receptacle in the fuse box where the relay plugs in. It looks ok although there is less resistance to me pulling a male end out on one of the receptacles.
May, 16, 2008 AT 4:32 AM
I am assuming that you tested the coolant sensor and the fuel pressure and didn't find a problem. A Passlock system is not a security system, it is an anti-theft system. A security light will light up in the dash board if your truck has it--I'm pretty sure it does. Anyway--the passlock system relies on a certain cranking resistance, in the ignition switch circuit, to start your engine. The ignition switch has a resistor in it that provides this resistance -and- this resistance value is unique to your truck. Sometimes this resistor goes bad--especialy when there is an aftermarket security system installed--because (usually) an aftermarket security system is spliced into the passlock system in some way. A loose connection or something like that, in your security system can cause the problem your having. The fuel pump connector has been a problem for quite some time. The fact that the engine has run fine for two years does not always rule out this connector problem, but it is less likely. The connector problem is--loose pins inside of the connector. Another problem area is the ground for the fuel pump. The ground corrodes where it connects to the frame. This very common and in my opinion one of the most overlooked fuel pump problems. This ground connects to the frame cross member, just before the gas tank. It's a black wire coming out of the wire harness for the fuel pump--just before the tank. Clean up this connection, or better yet, cut it off, crimp a new connector on the wire, and connect it to the frame with a stainless steel nut and bolt.