5.0 in an 87-94 bronco?

[rjewkes]

if it matters i can get the actual year on the bronco for you.

The question is the 5.0/302 in this beast has a bad injection system. it is efi what i am asking is will the intake from a 72 302 carb fit on this engine and work?

[70shortwide]

i think he means will it work for his bump. yes it should. you will need an electric fuel pump, maybe more. some will know exactly what it will take

[Dragon]

A basic engine scan can tell you what cylinders are getting too much fuel a common problem on older engines and a major mileage destroyer. If it tells you cylinder 2,5 and 8 is weak it probably is a bad fuel injector. You then drill down to a compression check and if that passes you have bad injectors. They can be so bad as to cause hydrostatic lock breaking the motor.

[rjewkes]

ok just trying to see if a bronco on the tow lot would be worth fixing. the boss could probably take it outa my check for a while.

[70shortwide]

o, gotcha. i was wrong

[willowbilly3]

oops, double post. Why does it do that? I hit submit and I am still at my typing window, thought I hit preview or something so I submitted again.

[willowbilly3]

Why was it towed? What did the previous owner muck up before he abandoned it? Like Dustin said, the system is fairly simple once you get the hang of it but often some unknowing "enthusiast" will mess up way more stuff than he fixed and you have to find all that.
Often it isn't anything with the computer, just plug wires and stuff. Key it and use a small screwdriver to poke down the schrader valve (looks like a tire valve in the shiney fuel rail pipe thingy) If you don't have good pressure there, like 40 psi, then the pump is shot, filter plugged or no juice to pump. Then you can use a test light across one of the injector plugs to see if the injectors are pulsing. So, if they are pulsing and have pressure you have the basics of the fuel system.
for example, I got on in my shop once that had a head job and would never idle down, went through all the flow charts and was scratching my head. I finally put on the breakout box and found they had switched the connectors from the coolant temp sensor and the air charge temp sensor. A broke one is easy to fix, a monkeyed up one can be a hundred times worse. My bet- one in a towing yard is the latter. Although I did see a really nice late model Bronco get towed from the airport once, still had the lady's purse in the front seat and they never did find her.

[FordTruck]

if it matters i can get the actual year on the bronco for you.

The question is the 5.0/302 in this beast has a bad injection system. it is efi what i am asking is will the intake from a 72 302 carb fit on this engine and work?

What part of the EFI set up do you need I think we have a whole EFI stuff on the motor in the 95 van we have the motors locked up but I'm shure all of that stuff would be ok. Let me know

[averagef250]

WB's right. Start simple. Check spark first. The ignition system sends the tach signal to the EEC. If the EEC doesn't get a tach signal, no fuel is going to be sprayed. After you establish spark verify fuel pressure. Faulty fuel pumps are common on the earlier EFI trucks. If you have fuel pressure check to ensure the injectors are firing by using a test light to check the ground side of the injectors (the injectors are always hot, the EEC grounds them to fire).

If it starts or tries to start, but coughs and smells extremely rich check the MAP sensor. If the vacuum line or the wires to the MAP are unplugged the engine will run rediculously rich. If the engine starts but will not idle check the IAB. If the engine runs, but the throttle is erratic, RPM's hang or the thing dies for no reason at a certain position of the gas pedal the TPS is at fault.

These are enough to get you started. The EEC has it's own diagnostics as well that will help you figure it out if you run a self test. Fiddle with the thing and you'll start seeing just how simple this EFI stuff is.

Also, don't spend a fortune on replacing sensors you think are at fault. U-pullit is chock full of ford EFI cars and trucks and the interchangeability of the sensors is huge. TPS, IAB, EGR, etc are the same for a huge number of cars and trucks from the mid 80's through the late 90's. Spend $20 grabbing a handful of each sensor and you've now got an EEC-IV troubleshooting kit.

[rjewkes]

Ok Boss bought and it ran but stopped sending the ignition pulse one day so he towed it there, his mechanic buddy is saying carb it.

Is this ignition pulse he speaks of the same as the tach pulse? or are they different? i can see on the rear drivers end of the manifold an unplugged plug it is grey with two wires on it. didn't see the wire colors though.

[Ranchero50]

Usually I'd say TFI related. Go out and loosen the ditributor, turn the key on and move the dizzy back and forth. You should hear the injectors pulse and the coil fire a spark. Two minute check that tells you a lot. If the coil fires and the injector pulse the puter should run the engine. If it doesn't, do a junk yard TFI swap or complete dizzy.

Most problem with those engines were the crappy hard vacuum lines that break everywhere.

Jamie

[willowbilly3]

Maybe look around the yard for a similiar equipped vehicle. If you don't have any test equipment (volt/ohm meter and test light) you can try swapping other components. TFI ignition module is a pretty easy swap and the fast way to test it is try a know good unit. Most are right on the distributor but I noticed my 92 351 has it mounted to a finned heat sink on the drivers inner fender back by the hood hinge. I think those are the same from escorts to 460s for may years.

[rubiranch]

The first thing I would check is the ground wire that either attaches to the negative battery cable or bolts to the radiator support, it is the main ground for the PCM and every sensor except the O2 sensor. If this ground becomes corroded and looses it's connection the engine will either not start or run very poorly after it does start.

O2 and MAP sensors were the two most common sensors to fail, very few coolant temp sensors failed and most ACT sensors just got contaminated from being exposed inside the intake and can be cleaned off with MAF cleaner.

I can't remember what year they changed from a speed density to a MAF.

I would fix the EFI long before I would ever convert it to carburetion.

[willowbilly3]

The first thing I would check is the ground wire that either attaches to the negative battery cable or bolts to the radiator support, it is the main ground for the PCM and every sensor except the O2 sensor. If this ground becomes corroded and looses it's connection the engine will either not start or run very poorly after it does start.

O2 and MAP sensors were the two most common sensors to fail, very few coolant temp sensors failed and most ACT sensors just got contaminated from being exposed inside the intake and can be cleaned off with MAF cleaner.

I can't remember what year they changed from a speed density to a MAF.

I would fix the EFI long before I would ever convert it to carburetion.

Good advice. I have seen those on the inside upper lip of the drivers fender too.
If the O2 or Coolant temp sensor craps out it will still run, just rich/rough. I only ever owned one Mass Air Flow system and never had a lick of trouble with it, those were only 95-96 I think