The thread about the guy throwing in the towel made me think maybe I'll just ask here for some input... can't hurt... its not boat related, but thats what this thread is for right?
Ok, so I have a 1989 Ford F250, with a 5.8L (351w), automatic with AC and cruise (not that all that matters, but better to have all the details).
Truck also has dual gas tanks with electric switchover.
Truck only has about 50k miles on it (was my grandfather's before he passed and he barely used it).
I inherited the truck and have done all the maintenance on it for the last few years... regular tune-ups, oil changes, plugs, wires, filters, etc. I am an ASE master tech, so know what I am doing, but this one has me stumped...
Here is what happened...
My dad had the alternator changed on it when he borrowed it from me... the place that changed it, was too lazy to remove the bracket the proper way, and so when they changed the alternator, they just used a torch to cut the bracket off the back... in doing so they let the vacuum hoses, and wiring for the EGR valve lay against the EGR tube coming off the exhaust manifold, and it burned the hoses and wires... the check engine light came on, and was throwing EGR codes...
Drove it like this for about a week or two, becuase I had no time to research it and even with the light on, it wasn't running that badly... Then all of a sudden the truck just suddenly lost all power... I can't even get it up to 30mph, and pardon the term, but it has no balls at all anymore... when you try to drive it, it starts to lose power over about 2k RPM, and it is also losing engine vacuum as the RPM increases (a lot more than it should), because the brake pedal gets hard from loss of vacuum to the power booster...
First thing I did was to scan it for codes for the CEL (check engine light)and it popped a bunch for the EGR system... I have replaced the EGR valve (failed vacuum test), replaced the vacuum lines that were burned, replaced the pig tail for the EGR valve that was burned, and the EGR position solenoid (was rotted). Now, no more check engine light or codes at all, but the truck still has NO POWER... so even though these things occured at around the same time, I don't think they are related... and more of a coincidence...
Around this same time as the power loss, it also sprung a small coolant leak in a bypass hose under the intake manifold, this was spraying coolant up into the TPS, and After running some more tests, the TPS failed its volt range test (Thottle positions sensor). I thought that maybe it wasnt advancing the engine after idle, and hence loss of power. I have also replaced this, and the coolant bypass line.
I found 2 burned plug wires at the boots where they may have been arcing spark, so new set of plugs, plug wires, cap and rotor just to be sure.
Still wont go...
Checked the backpressure and unbolted the exhaust prior to the catalytic convertor, and its fine, no problems, but still no change, truck wont go.
Check the fuel pressure to the injectors, also within specs so its not a fuel starvation issue... (checked the injectors themselves one by one too, and they are fine also).
The truck will crank and start right up just fine, and runs fine under 2k RPM, but past that it starts to chug and bog down and the power loss kicks in...
I have run a compression test, and all 8 cylinders are within specs too...
I was thinking it was the distributor not advancing the timing, but that tested ok as well...
So at this point I am out of things to test and out of ideas as to what may be wrong... I have never in 20 years of fixing cars had something I can't repair, and this one is just got me totally stumped! (Even worse its my own car and not a customers!). Sadly I dont have a full engine scope where I am at, just a snap on scanner and standard testing tools, but I have run the gambit on anything I can think it might be... its acting like fuel starvation, or lack of timing advance as the engine RPM's increase...
I too am ready to throw in the towel on it and tow it to ford to check it out... but I dont have the money for this, so I thought I would run it by you guys for any last minute ideas...
So summary:
New EGR Valve, EGR solenoid, EGR pigtail, EGR position sensor
New TPS (Throttle position sensor)
New cap, rotor, plugs, wires
New coolant line
New vacuum lines
Replaced fuel filter
Tested Fuel pressure and injectors
Tested Distributor and timing/timing advance
Tested exhaust backpressure
Truck starts and runs fine up till around 2k RPM, then goes bleh...
/edit - Forgot to mention, it doesn't matter which gas tank its switched too, it acts exactly the same on either tank.
So any thoughts on this one? I am about to drive it into the river (slowly if I make there LOL), and call it a day!
Ok, so I have a 1989 Ford F250, with a 5.8L (351w), automatic with AC and cruise (not that all that matters, but better to have all the details).
Truck also has dual gas tanks with electric switchover.
Truck only has about 50k miles on it (was my grandfather's before he passed and he barely used it).
I inherited the truck and have done all the maintenance on it for the last few years... regular tune-ups, oil changes, plugs, wires, filters, etc. I am an ASE master tech, so know what I am doing, but this one has me stumped...
Here is what happened...
My dad had the alternator changed on it when he borrowed it from me... the place that changed it, was too lazy to remove the bracket the proper way, and so when they changed the alternator, they just used a torch to cut the bracket off the back... in doing so they let the vacuum hoses, and wiring for the EGR valve lay against the EGR tube coming off the exhaust manifold, and it burned the hoses and wires... the check engine light came on, and was throwing EGR codes...
Drove it like this for about a week or two, becuase I had no time to research it and even with the light on, it wasn't running that badly... Then all of a sudden the truck just suddenly lost all power... I can't even get it up to 30mph, and pardon the term, but it has no balls at all anymore... when you try to drive it, it starts to lose power over about 2k RPM, and it is also losing engine vacuum as the RPM increases (a lot more than it should), because the brake pedal gets hard from loss of vacuum to the power booster...
First thing I did was to scan it for codes for the CEL (check engine light)and it popped a bunch for the EGR system... I have replaced the EGR valve (failed vacuum test), replaced the vacuum lines that were burned, replaced the pig tail for the EGR valve that was burned, and the EGR position solenoid (was rotted). Now, no more check engine light or codes at all, but the truck still has NO POWER... so even though these things occured at around the same time, I don't think they are related... and more of a coincidence...
Around this same time as the power loss, it also sprung a small coolant leak in a bypass hose under the intake manifold, this was spraying coolant up into the TPS, and After running some more tests, the TPS failed its volt range test (Thottle positions sensor). I thought that maybe it wasnt advancing the engine after idle, and hence loss of power. I have also replaced this, and the coolant bypass line.
I found 2 burned plug wires at the boots where they may have been arcing spark, so new set of plugs, plug wires, cap and rotor just to be sure.
Still wont go...
Checked the backpressure and unbolted the exhaust prior to the catalytic convertor, and its fine, no problems, but still no change, truck wont go.
Check the fuel pressure to the injectors, also within specs so its not a fuel starvation issue... (checked the injectors themselves one by one too, and they are fine also).
The truck will crank and start right up just fine, and runs fine under 2k RPM, but past that it starts to chug and bog down and the power loss kicks in...
I have run a compression test, and all 8 cylinders are within specs too...
I was thinking it was the distributor not advancing the timing, but that tested ok as well...
So at this point I am out of things to test and out of ideas as to what may be wrong... I have never in 20 years of fixing cars had something I can't repair, and this one is just got me totally stumped! (Even worse its my own car and not a customers!). Sadly I dont have a full engine scope where I am at, just a snap on scanner and standard testing tools, but I have run the gambit on anything I can think it might be... its acting like fuel starvation, or lack of timing advance as the engine RPM's increase...
I too am ready to throw in the towel on it and tow it to ford to check it out... but I dont have the money for this, so I thought I would run it by you guys for any last minute ideas...
So summary:
New EGR Valve, EGR solenoid, EGR pigtail, EGR position sensor
New TPS (Throttle position sensor)
New cap, rotor, plugs, wires
New coolant line
New vacuum lines
Replaced fuel filter
Tested Fuel pressure and injectors
Tested Distributor and timing/timing advance
Tested exhaust backpressure
Truck starts and runs fine up till around 2k RPM, then goes bleh...
/edit - Forgot to mention, it doesn't matter which gas tank its switched too, it acts exactly the same on either tank.
So any thoughts on this one? I am about to drive it into the river (slowly if I make there LOL), and call it a day!
.
