This is one of the best solutions to this problem that I have seen. Paul- very well worded in your instruction. I'm going outside right now to test this out on my truck. Like most of you, I wish I would have found this earlier. Excellent.
Did any of you guys have any hesitation at idle also? I have an E-150 w/ the 4.9 I just bought from a guy and he said , it's been a good truck but it has this hesitation at road speed. It sounds similar to what you described, It runs smooth then jerks and snatches like the rear and trans are gonna fall out. I've changed the usual stuff and did notice that if I unplugged the MAP sensor it ran smooth as silk at idle but changing it didn't help.
I just bought my dad's 91 F150 4.9I6 with 68k and a 5-speed. It has been doing this forever. I am really excited to try to fix this problem. However, I am unable to find the instructions on how to do this. If anybody knows the link or how to do this please let me know.
I just made a restrictor plate yesterday and it works. I'll take a shot at explaining how I did it.
First, follow steps in Chilton or Haynes and remove EGR valve. Remember to disconnect neg battery cable (to reset computer)
1. Scrape off old gasket and clean surfaces.
2. Purchase 2 EGR gaskets and use a sharpie to trace the gasket onto the sheet metal or aluminum you are using.
3. Use tin snips to cut around the outside and then with a piece of wood underneath use a 3/8" steel drill bit for the bolt holes and a 1/8" bit in the center of the top hole where the exhaust flows through.
4. Put a gasket on each side of plate and thread bolts back through everything. I didn't use gasket sealant, but I suppose you could.
5. Tighten bolts back on truck and make sure everything looks snug and tight.
6. Reconnect everything and test drive. Check engine light should stay off and performance should be greatly improved.
i've got a 93 f150 and my problem is when the engine is idleing and i give it just a little gas the engine tries to die then continues to rev like it should. i had a similar problem with a 91 ranger only it would accually die. i replaced the tp sensor on the ranger which fixed the problem right away. i ohmed the tp on the 150 and it looks good. also the 150 chuggs it's *** off, i only notice it when taking off from a stop only in 1st gear. it might do it in other gears i just never noticed. i replaced the fuel filter the other day which i think took care of the chugging problem. it's chugged twice since rather than every time. i've still got a problem with it trying to die when i give it gas. i think i have a pretty good understanding of how the restrictor plate works. it restricts the exaust gas going into the intake. now, my question is if i eliminated the pipe going from the exaust to the egr valve wouldn't that have the same result? i'm asking because just after i bought the truck the exaust system was so rusted that the pipe coming off of it going to the egr broke off. i welded it back on and sealed it with muffler seal. if i took it back off and welded the gaping hole in the exaust pipe the gas wouldn't even be a factor, right?
I would check your vacuum lines first. Pull each line off the vacuum tree on the intake manifold and suck on it, they should all hold vacuum.
Troubleshooting isn't about thinking about what the problem could be, but is about logicaly going step by step through the basics and finding what the problem is.
This is my first post, and a big thankyou.
I recently bought a '94 F150 with a 300 and 5spd. It needed a serious tune-up and some tlc, but is shaping up. What I couldn't fix was the missing/bucking from 1700-2000rpm. Yesterday I tried the EGR pipe removal trick, and today had a transformed truck to drive! What a difference. Thanks guys. Now I need some aluminium to do the job properly.
O.K. Fellas....Here goes.
I have been following this post for some time. My truck is doing the same thing. 95 xl 4X4 with a 5 speed. Mildly Rough idle, and bucking at 1/8 to 1/4 throttle, enough to **** me off and spill my coffee if I am not paying attention...............
So I cleared the computer by disconnecting the battery, and did the restrictor thing....NO LUCK. Can't find a vacuum leak, and all the small gaskets are good. Even checked with a decent shot of propane from an unlit torch and can't get a hint of leaks.....Sent it to my buddies shop for the fuel injector cleaning service....He hooked it up and ran it until it quit running and left it like that over night......Now it is worse.
You guys NEED to eliminate vacuum lines potentially being a problem first. Simply not finding a problem is NOT good enough.
Take each line off the manifold tree and suck on it, they should all hold vacuum. Do that first.
i have the same problem 95 150 6cyl has driven me nuts so will be makeing a restrictor this day thanks for the help. know a guy who spent 600dlrs at the ford dealer with no cure,dont think i will tell him for a whie may be blood let other wise