My 1987 Bronco ll 4x4 is only getting about 8-10 miles to the gallon!I posted on a Bronco site where the average mileage acording to those owners is 18-26 mpg!You can literally watch it suck gas, ate up almost a quarter tank on a 30 mile trip to work tonight.The suggestion was a failing fuel regulator or leaky injectors.I dont smell gas though.The only thing i smell is oil from the valve cover gaskets.It sounds great.I do hear what sounds like a sputtering when i accelerate (vacuum?) but that could just be the engine.You do have to push it a little before it catches on the highway and it hard shifts but im in the process of changing the filthy fluid thats been sitting in it.It hadnt been driven it a couple years.I just put a new cat converter,major tune up,EGR valve and cleaned ports,oxygen sensot, map sensor & both fuel filters and o-ring- the canister was missing.I know it needs an air flow idle sensor,what could this be?What is the labor on a regulator?How easy is it to check?

 

I feel with you. I got a Bronco II 85 2.8l V6 carb. My gasmilage is about 12m/gal and know how bad it feels to look out for a gasstation every 100 mi. I am interested in any tips to improve that 'sucking' condition. So I'll watch this port closely to get some inputs for my truck. I'm really looking forward to hear what gasmilage other owners got. Personally I would be happy with 20 mi/gal. I hope that's no illusion. Thx for your post.

 

I have an 87 Bronco II , 4WD, automatic that gets about 25-26 around town and nearly 40 on the highway. It started doing that (getting very poor gas mileage) a couple of years ago and the problem was a bad IAC sensor, along with a marginal O2 sensor.What I did was, first run a spray can of throttle body cleaner down it's throat, then replace the IAC sensor and O2 sensor and it got back to where it was supposed to be. There was also a recall on the ignition module of these things, but that would more than likely function correctly until it failed entirely, kind of like a light bulb. Good luck.

 

hmm .. got a stupid question: what is a IAC sensor? and are they used in 85 V6 2.8l 4WD 2 barrel carburator models? after some minor adjustments and new spacer gaskets I happily improved my gasmilage from 12mpg up to unbelievable 15mpg. I know that I still got a mess in the vacuum lines and I found a book especially covering these issues. Right now I keep quiet cuz the gasprice in my area is $1.93/gal.But as anybody knowsthat will change soon again (up). Any support will find my appretiation.

 

nearly 40 MPG ????