Good morning all. I am having a problem with my new(to me) 86 F150 302.It starts and runs just fine and does most other things it's supposed to do except that when it is out on the road and warmed up as soon as I apply throttle is bogs down and misses untiI take my foot off again.As stated,it's new to me and spent several years standing before I got it. Thinking try basics first I replaced all plugs and plug leads(Plugs were just rustballs).No improvement so my thoughts turned to the MAF sensor. It says in my book.(Haynes) that it is in the air cleaner housing but there is nothing in the air cleaner housing except the air cleaner,and no evidence of there ever having been anything in there.My question is does this model even have one and if so where are they hiding it.Help would be appreciated.
Geoff69

 

Hey geoff69a1, I didn't think it should have a MAF sensor so I had a look at my 1986 F150. It is fuel injected as I am sure yours probably is too and it does not have a MAF sensor but it does have a MAP sensor which I believe is mounted on the right inner fender next to the starter solenoid. The PCM should use it to calculate air flow. I think I would start with a new fuel filter first and if you have a pressure gauge you should check your fuel pressure.

 

The other thing is to pull codes from the computer.
I don't know how to do this but if you can do a search on here for how to do this.
Dave ----

 

No MAF sensor on your truck. The MAF or Mass Air Flow sensor is used on vehicles that measure the actual air flow in to the engine or a mass air flow system.

The early Ford EFI systems were speed density systems. They used engine RPM throttle position, manifold pressure, vehicle speed and a set of pre programmed tables to determine the air flow into the engine.

The easiest thing to do as mentioned is to pull the codes.

I personally hate messing around with test lights or an analog meter to pull the codes and would rather just cough up the $20 for a code reader.


I have the same one as on the link that I have been using for over 25 years now, makes the job a whole pile easier.

 

You can google "eeciv codes" and you can learn the format and how to do the test, no matter if you use a testlight, old voltmeter, or a code reader. If you are going to work on this truck, you need to know how to get codes from the computer.

 

Thanks guys,I'll stop looking for it then.With regard to the fuel supply I did renew the filter along with the intank and high pressure pumps so I don't think the problem is there but I will get the pressure checked.Again,thanks.
Geoff69

 

When you get to the Code reading part;

Engines are easier to diagnose over the internet when all the codes are listed, and in order of test.
KOEO - (O) Self-Test Codes =
KOEO - (C) Continuous Codes =
KOER - (R) Self-Test Codes =

 

Thanks for that ink Mathew,I sent of for the reader and the cord.In the meantime I replaced the distributor cap on the off chance it was tracking,would have been a cheap fix if it had worked.Anyone got any other ideas.If it is a fuel blockage problem it's between the filter and the engine,I replaced everything else.