hey people i still haven't got around to those bearings yet but here is question for the books..my 1986 bII 4x4 5 speed runs great around town at ilde and in thew woods but if youi take her on the interstate and get her up to say 70 or so for about thirty minutes of holding a steady speed she starts to run like poooooooooo!!!! finally it will get so bad that she is will only go about 45 to 50 mashed to ther floor!!!! then if you pull of and let her sit for about thirty minutes she i s good for another thirty mile sprint i have taken her to the ford garage and had her looked at and they replaced a sensour and said all was well but next time i drove at 65-70 for 1/2 hour same thing!!!!!!

i took it back the said they could not make my truck do this ( i know they just didnt drive it the way i am talking about ....thirty minutes of a steady speed of 65 to 70 an flat open road) and looked at me like i was nutz!!!! this truck starts to run like it is has on three plug wires off!!!!!im not talking about a slight miss i mean 45 is about top speed!!! and a klunky 45 at that

so i take the ole bronc to my friendly shade tree mechanic he thought worn lifters and so he replaces the lifters this seemed to help for about a month then same thing....

i have replaced plugs wires and dis.cap

i live in a small town in tennessee and i hardly ever drive at a steady speed for thirty miles the roads are all curves and hills so i only see this problem if i take my truck out of town so this problem is a really easy one to forget about until you want to take the 4x4 on a trip .....and a mechanic doesn't seem to want to spend the time to drive this thing thirty miles away to try and get it to act up... so there you have it my truck is trapped on this town which really annoys the hell out of me.....

this truck starts on the first hit 100 degrees out or 25 rain snow or sun. the truck runs great driving it all day around town ,on the country roads, or crawling around in the mountain trails..... it does not use in oil it does not smoke it does not knock or nothing it does have that typical bII lifter rattlie sounding v6 thing going but i have never heard one that does sound a little loud out front plus my truck has glass packs and a not so tight seal where the exhaust manifolds meet the pipes( looks like some one skipped the donught gaskets but i don't care about the noise i sorta like it)has no vacum leaks and has good oil pressure.......does anyone have a clue... ilove my truck and i think is sucks not to be able to take it where i want.... what the hell could cause this problem.......





help please

 

Get a fuel pressue gauge and hook it to the fuel rail. Run the hose under the back of the hood and tape the guage to the hood where you can see it. Then take it out on the highway for a cruise and see if the pressure drops off. If it does, could be a weak fuel pump, clogged filter, or a poor ground to the tank. Start with the cheap fixes first. Run a ground wire from the lip of the fuel tank to somewhere on the frame. (Just make sure you don't drill a hole into the tank!) Check the filter next. I'll bet you'll find it somewhere in the fuel system.

 

Get a fuel pressue gauge and hook it to the fuel rail. Run the hose under the back of the hood and tape the guage to the hood where you can see it. Then take it out on the highway for a cruise and see if the pressure drops off. If it does, could be a weak fuel pump, clogged filter, or a poor ground to the tank. Start with the cheap fixes first. Run a ground wire from the lip of the fuel tank to somewhere on the frame. (Just make sure you don't drill a hole into the tank!) Check the filter next. I'll bet you'll find it somewhere in the fuel system.

 

&'s right, sounds like a fuel thing similar to what mine used to do. I found a broken power lead to the low pressure (in tank) pump. I repaired the wire, replaced the pump and sending unit and replaced the filter and she ran like a raped ape untill I lost my second tranny in as amny months so I sold it to a guy in Texas for a parts truck.

 

Also try pulling the codes. FYI, an exhaust leak there can cause the O2 sensor to read lean from the fresh air being drawn into the system.

 

It could also be a clogged cat converter,that could also be why you have the exhaust leak.Is the exhaust leak before the cat converter?I am an import tech so I am not that familar with fords.But I have had some of the imports loose power from a clogged and then after the pressure would bleed off they would be fine.Also the guy I got my BII from said he had a bad fuel pump relay that would act up intermidantly,I might try a relay first since they are so cheap.

 

thanx everyone i ll check pressure filter and all the ground connections....some brush or debri could have broken something under there easy... but i still dont under stand why that would let it run good except for after thirty minutes of 70 on cruise control....

i can drive all day long starting and stopping and 30 to45 to 35 to 55 to 65 to 70 ,then stop at light ,then slowing for the curve ,then back to 70 then slowing for the slow poke granny then speeding back up or running the heck out of it in the mud... all day long in the woods but get on the road for 30 miles on cruise at 70 ( or off cruise just holding a steady speed of 65 to 70)

why would low pressure to fuel cause this? why would new lifters fix it for a while?
could the lifters back off and cause something like this.... if so can i adjust em up.... my lifters have that bar thing that hold the rocker arms on you know all the rocker arms are on this bar looking thing that runs the lenght of the head .... i guess i need a chiltons cause i dont know what any of this stuff is
even called.... i used to be able to fix anything on my '73 gt ranchero 351 cleveland....but it was not infested with gremlins .......

does anyone have a bronco II that does not have that rattlie loud sound out front. all of them i have been around have that lifter chatter loud clickie sounding engine.....as i said before i don't care about the rackett ( i used to run around with uncapped headers on my camed to death 351c) but i was just wonering why all these 2.9 sound so loud i have a 4.0 v6 '96 winstar and it is quiet as a kitten ... whats the deal on these 2.9s???

oh where/what is the o2 senser... what is all this talk about pulling codes? please forgive my ignorance....how/ what / then what do ya do with them... i know its on board computer stuff , right??? can i go to auto zone and have em hook it up?????i don't have any electronic gadgets to read this stuff....so clue me in what do i need and what do i do with it please.....



thanx

 

oh almost forgot the cat. converter is long gone. i have staight pipes into glass packs.........no inspections here!!!!!!! shes loud and she breaths free...who ever put on the exhaust didn't do the best job on the front. where the pipes join the manifold there is lots of play. is there not supposed to be a donut gasket or something there... mine is just a loose pipe to manifold connection...i have tried to tighten this but the bolts are really stuck and really hard to get to.....

i just got home with my new front wheel bearings.according to AutoZone there are two for my truck and no way to tell dif. without trying em on so i got em both so thats the project for tomorrow....any tips?



peace people

 

It is on board computer stuff. Your engine uses a computer to control fuel mixture, timing, and other things, rather than mechanical controls. BII's engine management system is designated EEC-IV (to distinguish it from EEC-I, II, III, and V). EEC-IV codes don't require any fancy gadgets -- a paper clip and a test light/voltmeter work well. See "tests" at www.dalidesign.com/hbook/eectest.html Be sure to follow the instructions.

 

I never had a lot of noise with mine with over 120,000 on the poor old 2.9 except once when I was on the road and the oil level got low. If you don't want to use the old jumper wire trick to get codes Autozone and several others carry a code reader for about $35 if I remeber right and it just plugs in. You have to count the flashes but that's it.

 

thanx $35 sounds like a deal. I'll pick one up......ias to loud out front dont mean alot of noise just that distinct 2.9 whirl, chatter maybe my lifters are too loose i am going to review past post and see if you guys have all ready covered this........




thanx people

 

The O2 sensor is in the down pipe on the passengers side, top side of the pipe.

The 2.9s don't have a good top end oiling system so any decrease in oil pressure seems to get the lifters ticking. Have you checked the oil pressure? If you have the valve covers off you can check/readjust the valve train, some manuals will tell you 1.5 turns but 1.75 is the prefered number. You can modify the shaft and rockers to get some more oil up there if you up for that kind of work.