My 4.9 just died and will not start
#1
Junior Member
Thread Starter
Join Date: Jul 2011
Location: iowa
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
My 4.9 just died and will not start
I have a 1996 F-150 with a 4.9 it has always been reliable no matter what the conditions, but 2-weeks ago I pulled it out of the driveway and went 1-block before it just died and had to be hauled home. I am stumped! i have gone through the ignition system and it has a good spark. I have put a pressure gauge on the rail and it reads 49 pounds. The only way I can get it to kick is to inject gas into the plenum and it barely runs for a second. I cannot find any bad fuses, I do not know what to try next, any ideas!!!
#3
Sounds like a fuel pump to me.
When you checked the pressure was the key at the on position? Maybe it was putting out pressure but when the engine is running it can not keep up.
Same thing happened to my sister about 2 weeks ago. Driving her car home from work.. gets to a red light and glug glug glug... dead. Car would turn over but would not start.
She called me, I drove down there with a can of ether and lightly sprayed some in the plenum.. Car ran great (until the flow of ether stopped).
Replaced fuel pump and fuel filter and it runs like a dream again.
An easy way to check is to put the key in the ignition and turn it to on. When you turn it to on ( but do not start it) the fuel pump will run (sounds like a buzz). If you dont hear that maybe you have a bad pump.
I could be wrong... like you said you have fuel pressure at the rail but is the pressure consistant?
When you checked the pressure was the key at the on position? Maybe it was putting out pressure but when the engine is running it can not keep up.
Same thing happened to my sister about 2 weeks ago. Driving her car home from work.. gets to a red light and glug glug glug... dead. Car would turn over but would not start.
She called me, I drove down there with a can of ether and lightly sprayed some in the plenum.. Car ran great (until the flow of ether stopped).
Replaced fuel pump and fuel filter and it runs like a dream again.
An easy way to check is to put the key in the ignition and turn it to on. When you turn it to on ( but do not start it) the fuel pump will run (sounds like a buzz). If you dont hear that maybe you have a bad pump.
I could be wrong... like you said you have fuel pressure at the rail but is the pressure consistant?
#4
Senior Member
Sounds like a fuel pump to me.
When you checked the pressure was the key at the on position? Maybe it was putting out pressure but when the engine is running it can not keep up.
Same thing happened to my sister about 2 weeks ago. Driving her car home from work.. gets to a red light and glug glug glug... dead. Car would turn over but would not start.
She called me, I drove down there with a can of ether and lightly sprayed some in the plenum.. Car ran great (until the flow of ether stopped).
Replaced fuel pump and fuel filter and it runs like a dream again.
An easy way to check is to put the key in the ignition and turn it to on. When you turn it to on ( but do not start it) the fuel pump will run (sounds like a buzz). If you don't hear that maybe you have a bad pump.
I could be wrong... like you said you have fuel pressure at the rail but is the pressure consistent?
When you checked the pressure was the key at the on position? Maybe it was putting out pressure but when the engine is running it can not keep up.
Same thing happened to my sister about 2 weeks ago. Driving her car home from work.. gets to a red light and glug glug glug... dead. Car would turn over but would not start.
She called me, I drove down there with a can of ether and lightly sprayed some in the plenum.. Car ran great (until the flow of ether stopped).
Replaced fuel pump and fuel filter and it runs like a dream again.
An easy way to check is to put the key in the ignition and turn it to on. When you turn it to on ( but do not start it) the fuel pump will run (sounds like a buzz). If you don't hear that maybe you have a bad pump.
I could be wrong... like you said you have fuel pressure at the rail but is the pressure consistent?
#5
Junior Member
Thread Starter
Join Date: Jul 2011
Location: iowa
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Pressure gauge at the rail reads 49lbs and holds it there, it will not start, it has a new fuel filter and I can hear the pump run when the key is on. Multimeter shows 12.6 volts at the injector with key on "on" but it drops to zero when engine is cranking, is that normal?
#6
Senior Member
Pressure gauge at the rail reads 49lbs and holds it there, it will not start, it has a new fuel filter and I can hear the pump run when the key is on. Multimeter shows 12.6 volts at the injector with key on "on" but it drops to zero when engine is cranking, is that normal?
Trending Topics
#8
Those relays under the hood are supposedly interchangeable too so when you find the relay, just replace it with maybe the A/C relay or something insignificant just to see if it starts. If it does, you know that's the problem, If it doesn't, it saved you buying a new relay THEN finding out it wasn't the problem. Replace all relays in proper position before driving obvoiusly.
#9
Senior almost
I dont have my manual in front of me so it maybe off base but check to amke sure the fuel injectors are working both fuel and voltage, if all else fails check compression on number ine cylinder and find top dead center, verify distributor is pointing at one and that you get fuel from injector at one to verify you did not jump timing ...
#10
Gotta do it cheap!
Join Date: Sep 2011
Location: Texas
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
Honestly sounds like a computer problem, get the codes read, if there a whole bunch of codes thrown, its probably the ecm itself. They dont go bad very often, but it happens