My New-To-Me F150 Was Driving Great And Now Dying: Please Help!
#12
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Update:
I inspected the dizzy and found metal shavings. I replaced dizzy and ignition module. She starts quick now. Got her on the road for first test drive and she made it to 55-60 mph with only one off-the-start hesitation. Second and subsequent test drives, she reverted back to original symptom and bogged down around 45 mph.
No, motorcraft/autolight 2150
No, single occurrence and was probably residual moisture blow off.
Fuel pump was replaces by PO and I have nominal fuel pressure reading. (did not do a capacity test)
Will be installing tonight.
I installed the dizzy and timed it at idle and ~2000 rpm.
I inspected the dizzy and found metal shavings. I replaced dizzy and ignition module. She starts quick now. Got her on the road for first test drive and she made it to 55-60 mph with only one off-the-start hesitation. Second and subsequent test drives, she reverted back to original symptom and bogged down around 45 mph.
No, motorcraft/autolight 2150
No, single occurrence and was probably residual moisture blow off.
Fuel pump was replaces by PO and I have nominal fuel pressure reading. (did not do a capacity test)
Will be installing tonight.
Sounds like carb issues, but have you timed it yet to make sure it's set correctly? Timing being a little off and a dying carb could produce a lot of the symptoms you're describing. Look at the underside of the distributor cap for corrosion. If it's white residue and crusty, might as well replace that so that it's ruled out also.
I installed the dizzy and timed it at idle and ~2000 rpm.
#14
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Well Dang, I just replaced my carb and she is still losing the ability to accelerate once she gets up to ~45-50mph until I drop the speed down or come to a stop then she can accelerate to 45-50 again smoothly then looses acceleration again.
I have done vacuum and fuel pressure tests: normal.
I have replaced the ignition module, dizzy, plug wires, and carb. I timed her, inspected spark plugs, disconnected egr-tested and reconnectedand did a simple carb adjustment.
My next thought is check for blockage in exhaust.
Any thoughts?
I have done vacuum and fuel pressure tests: normal.
I have replaced the ignition module, dizzy, plug wires, and carb. I timed her, inspected spark plugs, disconnected egr-tested and reconnectedand did a simple carb adjustment.
My next thought is check for blockage in exhaust.
Any thoughts?
#16
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OFY! plus there are different styles of cats. If you have the new honeycomb style, most of the time they just crumble to dust. But they used to have wire and stuff in them. That can be a real headache to troubleshoot.
Sunday I went to replace the tailpipe on my 86' and the muffler had holes in it so I replaced that too. The truck is MUCH peppier!(I mean as compared to a 1 BBL L6 can be) I do think that the muffler had some clogs in it. The new muffler is super quiet too. And the truck runs a little cooler.
So there might have been some blockage.
I know you have thrown some coin at this. BUT, when done you will have a nice truck. If you have a single cat it should be like $110 from Rock Auto. Inspect the rest and I would just replace the whole exhaust. It might very well be 35 years old. Looks like Rock Auto has tailpipe, muffler and cat for 201$.
Sunday I went to replace the tailpipe on my 86' and the muffler had holes in it so I replaced that too. The truck is MUCH peppier!(I mean as compared to a 1 BBL L6 can be) I do think that the muffler had some clogs in it. The new muffler is super quiet too. And the truck runs a little cooler.
So there might have been some blockage.
I know you have thrown some coin at this. BUT, when done you will have a nice truck. If you have a single cat it should be like $110 from Rock Auto. Inspect the rest and I would just replace the whole exhaust. It might very well be 35 years old. Looks like Rock Auto has tailpipe, muffler and cat for 201$.
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Update:
Took the cat off and it looked like Grecian bathhouse drain. Swapped it out for a new one and she drove good through the city streets, Took her up to the highway, got her up to 60+mph a couple of time with no issue then on the third attempt, she did the same root problem- refusing to accelerate beyond ~45-50mph the decelerating until reaching a low enough speed for her to accelerate again back to 45-50 mph and repeating the cycle. *****.
My next thoughts are: pulling the muffler (was installed within the last year) off and checking for any blockage there. And doing a fuel capacity test. What are your thoughts?
Please, the ford powers that be, help me fix me truck! Amen
Have not taken the dizzy cap off to see if I have more shaving. I'll check it out.
That is what I keep telling myself
Took the cat off and it looked like Grecian bathhouse drain. Swapped it out for a new one and she drove good through the city streets, Took her up to the highway, got her up to 60+mph a couple of time with no issue then on the third attempt, she did the same root problem- refusing to accelerate beyond ~45-50mph the decelerating until reaching a low enough speed for her to accelerate again back to 45-50 mph and repeating the cycle. *****.
My next thoughts are: pulling the muffler (was installed within the last year) off and checking for any blockage there. And doing a fuel capacity test. What are your thoughts?
Please, the ford powers that be, help me fix me truck! Amen
Have not taken the dizzy cap off to see if I have more shaving. I'll check it out.
That is what I keep telling myself
#18
Senior
Ok, I am going to throw something out. Have you checked the rubber fuel lines between the tank and the pump. could be a pinhole/loose line letting the pump suck just enough air to screw thing up under load. I know the PO told you he replaced the fuel lines but I would double check the rubber just in case.
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1967 Tempest (12-02-2015)
#19
Wow...having exactly the same issues as Nosehair. My 1990 F-150...have had several folks over several years working to try and solve the issue...no luck so far. The current fella says that it is the Fuel Tank Selector Valve preventing the truck from switching tanks. I said that "I was not switching from front to rear tanks when this occurs" (runs fine, idles fine in driveway, but put it in gear and drive is a no. Soon as it is under a load, it misses, backfires, stalls, and finally just dies. Had my truck towed home several times. Then it starts right up a few days later. Then repeats the problem) The bigger problem is that FORD no longer makes the part...dealers cannot get it...suppliers don't have it! I am told that my only solution is to only run front tank. How does this happen?
#20
1990 F150 is now a lawn ornament! I own 3 F-150's. Won't buy another
Wow...having exactly the same issues as Nosehair. My 1990 F-150...have had several folks over several years working to try and solve the issue...no luck so far. The current fella says that it is the Fuel Tank Selector Valve preventing the truck from switching tanks. I said that "I was not switching from front to rear tanks when this occurs" (runs fine, idles fine in driveway, but put it in gear and drive is a no. Soon as it is under a load, it misses, backfires, stalls, and finally just dies. Had my truck towed home several times. Then it starts right up a few days later. Then repeats the problem) The bigger problem is that FORD no longer makes the part...dealers cannot get it...suppliers don't have it! I am told that my only solution is to only run front tank. How does this happen?