I have a 1985 F150 XL with the 302 fuel injected engine I had a brake booster put in 3 months ago while I was driving home it died so they towed it back and said fuel pump went bad they replaced both fuel pumps . Picked it up ran good let it sit in driveway for a couple days went to start it wouldn't start brought it to a different mechanic he suggested full tune up plugs rotor and wires picked it up ran great for a day or two then stopped again . Brought it to another mechanic he said the heat sensor was bad or something they replaced it went to pick it up only way to keep it running was give it gas until engine was warm so drove it home and all's it did was spudder and back fire the whole ride. Sent it back to that mechanic he said the wiring harness is **** so he replaced a bunch of wires now it will start and when it idles it boggs down almost stals and kicks back up to normal idle it does this for a couple minutes then idles fine but when u drive it it still spudder and has no power and back fires the whole time. Any help or suggestions would be greatly appreciated

 

Welcome to the FTE Larryh336

While your waiting on replies, I'd consider posting this in the " Regional " thread as well
here is the direct link; https://www.ford-trucks.com/forums/forum13/

The FTE has Members all over the world and most likely someone with more experience then
I have might chime in that could be of help or knows someone.

Good Luck !

 

I'd say step one is to pull the codes. Was it running fine before brake booster replacement? If so you may have a big vacuum leak from bad booster diaphragm /check valve/hose. As many guys have said before, new parts can be bad right out of the box.

 

Would you hear the leak if it was the booster ? When I changed it it was a loud air leaking sound

 

Pull the codes. Here's how to do it.

EEC IV Self Test hookup

 

Yup as franklin said pull the codes. Many of tech's today are not mechanics but R&R (remove and replace) men, as you have found out maybe that is why they call them technicians now and not mechanics lol ..
With the advent of computers in vehicles the percentage of techs that know how to properly diagnose problems it quite small and finding ones that can do it competently are few and far between.

Pull the codes and report back to us.

 

It is very hard to find a good mechanic in my area that can work on old trucks or cars . I am no mechanic but fix what I can in my driveway with the tools I have . Not 1 of the 5 shops this truck has been to did they say anything about pulling codes . Just wondering is this what I'm looking for ?
https://youtu.be/-YYQKssOEOs

 

The first CEL connected to the computer was 1987.

IOW you don't have a CEL to count the flashes, you'll need to use a test lamp or analog voltmeter.

There's a CHANCE the EMISSIONS light might function in the CEL's place but I have no verification of that.

 

As noted you will have to use a test light or an anlog meter. Back in the day dealers used the STAR (Self Test Automatic Readout later replaced with the STAR II ) to read the codes on EEC III and EEC IV systems. (these are NOT OBD 1 systems outside California)

If you don't want to mess with a meter or test light. You can pick up one of these guys

They have more functionality than the original STAR unit. I have had one for over 25 years now and it still works as good as the day I bought it.

 

So I have been buisy and haven't gotten around to look into pulling codes but can anyone tell me where I need to use the test light or the code reader to pull the codes from? Also it rained last night and today and I went out side to start the truck and it will not turn over just cranks and cranks and cranks but before the rain it would turn rite over just run rough and not much power. Any ideas?

 

So I have been buisy and haven't gotten around to look into pulling codes but can anyone tell me where I need to use the test light or the code reader to pull the codes from? Also it rained last night and today and I went out side to start the truck and it will not turn over just cranks and cranks and cranks but before the rain it would turn rite over just run rough and not much power. Any ideas?

 

As for the no-start when wet, take a look at your ignition - distributor & coil in particular. Look for wet wires, frayed wires, shorted connections, that kind of thing.

As for pulling codes, I think the connectors are near the battery? I forget for certain.

This site might help you:

Ford Ranger - Testing EEC-IV Equipped Engines

 

Behind the battery is the Vacuum Reservoir, Black Box;


On the other side of the Reservoir are the test connectors;

See the red connector in the picture, there is also a single grey connector as well.

 

Check to see if you have water coming in under your dash near the ECA/Computer......

 

No signs of water coming in . I put a new ecm in it today and truck fired rite up ran for a couple seconds and shut off then I started it again gave it some gas door 20 seconds and let off and it idled good but a little low and never shut off. Seems like when it sits a bit it won't idle till it's warmed up. Any ideas what would make it not idle untill warm? Thanks or all the help