Hot Rod Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
My truck has 114000 miles.Lately when starting it may turn over for 10-15 seconds before starting.Not so much in the cold but when it is warmer out.Any ideas?Thanks It is a v-8 4800 4.8? :confused:
 

·
Registered
Joined
·
261 Posts
novakidd 63

First is this fuel injected.
Second when was the last if any tuneup.
Third have you ever changed the fuel filter or sock in the fuel tank.

Just a few questions and probably the fuel filter and/or sock in the tank, may also need the injectors cleaned.

30dee
 

·
Administrator
Joined
·
18,400 Posts
I had problem where it acted like that...88 TBI.........The fuel pump relay wasnt working, so it would have to build up oil pressure before it would start.....Once it has oil pressure, it doesnt need the relay.
 

·
Registered
Joined
·
384 Posts
Sounds like it's fuel related... either the filter or the pump... change the filter first, it's cheaper and easier.
 

·
Save a horse, Ride a Cowboy.
Joined
·
5,122 Posts
Fuel pump cannot run if relay is inoperative. period.

1) Listen, is the fuel pump cycling when you just turn the key on, but you are not cranking the engine?
It should cycle about 2-3 seconds then turn off. Pump will cycle only once when the key is turned on.

(Hook up a fuel pressure gauge. Crank until pump cycles. Read pressure.= If you want to)

2) Try turning the key on and off several times to allow pump to multi-cycle. (Read pressure. Increase? Is the pressure high enough?)

3) Then crank, see if it starts immediately on cranking after multi-cycling.

If it does, you probably have a faulty fuel pressure check valve. The pressure is bleeding off with the engine not running. Multi-cycling or long cranking will restore the pressure and allow the engine to start.

The computer senses the firing cycle and runs the fuel pump continuously. If the engine ever stops for any reason, the computer will turn off the fuel pump automatically when the ignition pulses stop.

Common.

While you are there, check the fuel pressure idling with the vacuum hose on, and off. Line off should give you a higher pressure reading for full throttle operation... are both pressures up to spec?

Let me know what you find out. There is an easy way out if this is the problem.
 
1 - 5 of 5 Posts
Top