Just bought my first big bronco.
90 FS bronco, 351w, auto. small lift, 31's, soon to be 32's.
I only paid 900 for this badass truck, guy gave me 2 bf goodrich mud terrains with it. im the third owner, truck has 73k original miles.
I have a few questions about it though......
1. the alternator seems to be super weak, any decent/cheap upgrades, im not afraid of the junk yard, and would like to get more than 75a out of it.
2. it has developed a lil hiccup problem as well, with plenty of fuel, and a new filter, it spits and trys to die while driving sometimes, usually at low speeds. idea as to what it could be?
3. will a major tune up help this maybe...plugs, wires, etc.
4. check engine light on....put on code reader, says tps sensor, and temp sensor, but the gauge on the dash still works?

any help or ideas would be greatly appreciated. the only other bronco ive had was a bronco II, and i loved it. i have always wanted a big bronco, and when i saw this one, i couldnt resist.
here a link to a video of it.
YouTube - The New Project.........

 

Welcome to FTE and the Big Bronco Forum. We will do our best to get you the most accurate info we can.

The ECT sensor has nothing to do with the temperature sending unit for the gauge. The gauge has its own highly unreliable sending unit. The ECT sensor is mounted near the water neck and is what gives the ECM/PCM engine coolant temperature information. I am assuming you got codes that refer to the ECT and not the ACT sensor. The ACT measures the temperature of the air coming into the intake.

With the alleged alternator issue, before assuming the alternator is weak, have it AND the battery tested. I battery with a bad cell will put a constant draw on the alternator. Check the negative battery cable and the connections to the frame as well. Loose or corroded cables, clamps or corrosion and dirt will weaken the system. The Stock alternator in a vehicle that has no serious additional electrical loads added should be producing more than enough electricity to handle the system requirements.

With the stalling/sputtering issue, clean the IAC (Idle Air Control) valve. This is a valve/solenoid assembly mounted to the driver's side of the throttle body. They tend to coke up along with the throttle body and the idle suffers greatly. When you clean it be CERTAIN the any cleaner you use is safe for "sealed" or "coated" throttle bodies and safe for O2 sensors.

 

thanks greystreak....
i did clean the battery terminals, put new ends on the cables(the old ones were corroded), used some intake/carb cleaner on the IAC valve, and then tried it. Works much better now. Still got the CEL, but now it only says two codes......63 and 98 on the running test, and only 63 on the off test. it says in my little code book that 63 is the TPS sensor low voltage, and 98 is a hard fault code?
the truck runs worlds better now that the intake was cleaned a bit, and the battery/alt seems to be working much better, not a huge draw on it. i am still going to take it in to get it load tested though. when i rev the truck hard, the CEL goes away, and as soon as the idle comes down, it comes back on. like i said, the truck seems to run great though.
here another vid to show it running after all that i did to it.

YouTube - Bronco Cold Start up and Revving

thanks again for your help and warm welcome.

 

You could clean the connector between the TS (throttle position) sensor and the harness and see if it helps but I'd be willing to bet the cure is going to require replacement. I'll update this post when I get a minute to have a look at some reference information on Code 98.

 

i will try that tomorrow then and see. thanks again for the help.

 

dayum! flashed it up past 5 grand....

900 dolllars?!

 

lol, yep. $900, and with 2 bf goodrich mud terrains comin with it, i couldnt turn it down. she isnt without her little issues, but i knew it was a steal. and she runs pretty good. i call her bellona, the roman goddess of war. shes loud, shes belligerant. i couldnt think of a better more fitting name, lol. hopefully she leads me on some fun adventures, my last BII did.

 

replaced TPS, CEL is gone, truck runs better than it has since ive had it. kind of a pain in the ***, but for 36 bucks, fixed it. now on to the fun stuff. lol.

 

go to Ford Fuel Injection and look into a 3G alt swap. there is a couple links once you get there to purchase a harness, 160amp or larger alt and soforth.

also isnt that odometer a 5 digit readout? if so how do you know its really not over 100k or 200k miles?

 

thanks for the info and links. def gonna be lookin into that. i do eventually want to put a serious sound system in it.

the mileage was verified through dmv. being im the third owner, it wasnt hard for them to look back and see when/who reg'd it, and mileage. i carfax'd it as well, but didnt come back with anything from that.

 

congrats on the low mileage

 

thanks. i feel like i won the bronco lottery. everyone thats seen it says, wow, the insides really clean for a 90. hahahha i almost, almost thought about doing a resto on it, but they werent bred to be pavement pounders......

 

where in oregon are you located?

 

eug/spfld area, more specifically, off of 32nd st in springfield. lol.

 

sorry, but whats the CEL?