88 F150 300 6cyl problem
03-28-2011, 08:14 PM
#1
Junior Member
Thread Starter
Join Date: Mar 2011
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
88 F150 300 6cyl problem
Ok, never once have a encountered a problem like this so i need some people to think outside the box. The truck cranks a little rough and has a rough idle. Thats not the problem though. From idle to full throddle, the idle doesn't change at all! At full throttle it just idles. The throttle body butterflies open as they should and all. We checked the timing belt, timing, all vacuum lines, map sensor, spark plugs, fuel pressure regulator, and a few other things. We can't seem to figure out what is wrong. If you have encountered this problem before your advice would be greatly appreciated. Thanks in advance.
03-30-2011, 08:39 PM
#2
Junior Member
Thread Starter
Join Date: Mar 2011
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
UPDATE
Replaces injectors and still no help. Its almost like it has a clogged intake and not letting the motor get above 900rpm, even at full throddle. Noid light says all injectors are getting power also. This happened spontaneously, so its no like the motor wore the lobes off the camshaft. Any ideas would be helpful!
Replaces injectors and still no help. Its almost like it has a clogged intake and not letting the motor get above 900rpm, even at full throddle. Noid light says all injectors are getting power also. This happened spontaneously, so its no like the motor wore the lobes off the camshaft. Any ideas would be helpful!
03-30-2011, 09:39 PM
#3
Senior Member
[quote=Fosgate_Fan;821818]UPDATE
Replaces injectors and still no help. Its almost like it has a clogged intake and not letting the motor get above 900rpm...
So... this just happened out of the blue? What were you doing at the time? Driving it? You just started it and it wouldn't go or were you working on it maybe? If working on it, is it possible a rag or something got sucked in the intake somehow? If not, I'd check the compression to start. If that checks out the engine is most likely OK and you can look elsewhere. I'd check the fuel pressure first then ignition I suppose. Oh by the way, your engine has timing gears not a timing belt. But maybe you meant fan belt...
Replaces injectors and still no help. Its almost like it has a clogged intake and not letting the motor get above 900rpm...
So... this just happened out of the blue? What were you doing at the time? Driving it? You just started it and it wouldn't go or were you working on it maybe? If working on it, is it possible a rag or something got sucked in the intake somehow? If not, I'd check the compression to start. If that checks out the engine is most likely OK and you can look elsewhere. I'd check the fuel pressure first then ignition I suppose. Oh by the way, your engine has timing gears not a timing belt. But maybe you meant fan belt...
03-31-2011, 08:23 AM
#4
Junior Member
Thread Starter
Join Date: Mar 2011
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
[quote=BLS;822015]
It been sitting for a while. It ran ok then the slave cylinder went out. Replaced it and it never ran right scene. We checked compression, cyl 3 is bad, but going to drive it until it blows up. all others are 150-160. It had a skip so id say cyl 3 had bad compression to start. Timing from the distributor was checked and timing chain. I know it doesn't have a timing belt, lol, must have said belt without thinking. Thought it may be a rag and boroscoped the intake, its clear. Fuel pressure is 55 at the rail. Changed the fuel filter also. This thing has me stumped!
UPDATE
Replaces injectors and still no help. Its almost like it has a clogged intake and not letting the motor get above 900rpm...
So... this just happened out of the blue? What were you doing at the time? Driving it? You just started it and it wouldn't go or were you working on it maybe? If working on it, is it possible a rag or something got sucked in the intake somehow? If not, I'd check the compression to start. If that checks out the engine is most likely OK and you can look elsewhere. I'd check the fuel pressure first then ignition I suppose. Oh by the way, your engine has timing gears not a timing belt. But maybe you meant fan belt...
Replaces injectors and still no help. Its almost like it has a clogged intake and not letting the motor get above 900rpm...
So... this just happened out of the blue? What were you doing at the time? Driving it? You just started it and it wouldn't go or were you working on it maybe? If working on it, is it possible a rag or something got sucked in the intake somehow? If not, I'd check the compression to start. If that checks out the engine is most likely OK and you can look elsewhere. I'd check the fuel pressure first then ignition I suppose. Oh by the way, your engine has timing gears not a timing belt. But maybe you meant fan belt...
04-01-2011, 08:48 AM
#5
Senior Member
Oh my... Well, since you were working on it and then it started having problems it must have something to do with that. Guess I'd start by checking all the wires and everything. Unplug every wire connection, every relay, etc. Even the ones you've already checked ten times. No cheating! And even where you weren't working on the off hand chance it had nothing to do with what you did and it was just time for it to start acting up. If none of that helps I guess you need to read the codes. The computer will know what's wrong. Good Luck!
Last edited by BLS; 04-01-2011 at 08:53 AM.