hesitation, stalling, and idle troubles

[dozerbwt]

Hey everyone, I'm a newbie to broncozone and working on trucks in general. I have been scouring the threads and found alot of good info. Now to the problem: I have an 86 Bronco 302 5.0L EFI. This week it started to have hesitation during acceleration and sometimes even stalled. When I come to a stop it will idle for a few seconds and then it will hesitate for a second and then go back to a normal idle. When I got home yesterday I noticed that the inline fuel pump was still running. Would this have anything to do with the problem? Also when I fire it up it idles at a high rpm (1500) for a few minutes until it "settles in." It will start just fine when the engine is cold, but when the engine hasn't had time to cool down it takes a while for it to crank over. I have a twenty minute commute to work and in the morning I don't have any of these problems except for the inconsistent idle at stops. The other problems only seem to occur on my afternoon drive home when the outside temperature gets above 65 degrees. I have recently (February) replaced both fuel pumps, the fuel filter, alternator, battery, spark plugs, rotor, distributor cap, wire set, belts, and the ECT (Engine Coolant Temperature) sensor. Any help will be greatly appreciated.

 

[Shadow_D]

To me is sounds like the Fuel Pressure Regulator is bad. It is easy to replace and shouldn't cost more than $20.

 

[bidibronco]

Or some injectors that need attention?

 

[Shadow_D]

True, might want to get some injector cleaner in the tank for a couple of times

 

[BroncoJoe19]

If you have a fuel pressure guage you could do a fuel pressure test to see if there is a problem with your regulator. That may be what is causeing the pump to continue to run.

Would dirty injectors give an intermittant problem? I don't know, probably wouldn't be a bad idea to clean them though.

OTHO it could be a flaky Fuel pump relay, TPS, IAC, EGV, or MAP sensor.

The quickest and easiest way to get info on these sensors and actuators is to pull DTCs diagnostic troubleshooting codes.

Here is an instructional article on how to pull codes.

The only tools one needs of an '86 is a short jumper wire, and a cheap voltage meter.

http://www.fordfuelinjection.com/files/self_test.pdf

This will be of particular interest to those with 1984 through 1988 models, but is also excellent for those up to the 1995 models.

 

[Shadow_D]

Good source of info you are Joe

 

[dozerbwt]

Thanks everybody. I'll put some fuel injector cleaner in it and run the self diagnostic tonight. I'll let you guys know what happens tomorrow.

 

[bidibronco]

Don't expect fuel cleaner to work overnight. You'll have to give it some time.

 

[BroncoJoe19]

Good source of info you are Joe

Thanks... try I do... yes.

Much knowledge gained here... yes.

Thanks again,

joe

 

[muddinlate86]

check your dist. and your ign moduel,had sim.problems and my dist.was toast!!!!!!!!