1986 Ford F-150 truck shutting down around 40mph

Tiny
PHTD1990
  • MEMBER
  • 1986 FORD F-150
  • 5.0L
  • V8
  • 4WD
  • AUTOMATIC
  • 140,000 MILES
I have an 86 f150 with an 87 engine in it. It runs well in park or neutral. I can rev the engine with no issues. Take it on the road and around 40mph the engine almost shuts down and you can wait 30 seconds and it will try to take back off but it'll try to shut right back down again. I thought it was a fuel problem so I put a new fuel pump and injectors. I've asked everyone I know and no one knows. If you could help it would be much appreciated. Thank you.
Friday, January 2nd, 2015 AT 12:47 PM

10 Replies

Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
, AND WHAT ABOUT MR. FUEL FILTER?

YOUR TURN

THE MEDIC
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 3:28 PM
Tiny
PHTD1990
  • MEMBER
  • 4 POSTS
Fuel filter is new also. I pulled the fuel rails and there clean and when the pump was changed so was the fuel line.
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 4:15 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
WHAT IS THE ACTUAL FUEL PRESSURE?

SOMETIMES AUTO PARTS STORES WILL LEND/ RENT A GAUGE OUT

THIS IS TBI OR FUEL INJECTION?

IS THIS IT'S MAIDEN VOYAGE WITH THIS ENGINE OR IT HAS BEEN RUNNING FINE FOR SOME TIME WITH THIS NEWER ENGINE?

THE MEDIC
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
+1
Friday, January 2nd, 2015 AT 4:34 PM
Tiny
PHTD1990
  • MEMBER
  • 4 POSTS
Its feul injected and it ran with no problems for about five years and then it started doing this on my way home from work. I've never put a gauge on it but I could give it a try and make sure.
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 5:36 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
THAT WOULD ELIMINATE A POSSIBILITY BEFORE YOU THROW MORE PARTS AT IT

I'LL SEE IF I CAN GRAB ANOTHER 2CARFELLER TO AID WITH YOUR ISSUE

THE MEDIC
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 5:45 PM
Tiny
PHTD1990
  • MEMBER
  • 4 POSTS
Yea nobody I've asked knows. My only other thoughts on it is maybe the transmission is causing g it.
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 6:29 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
THE 1ST 7/8 OF MY LAST RESPONSE DID NOT SHOW UP

I'LL TRY AGAIN

THE MEDIC
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 6:42 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
TOO MUCH GOING ON HERE

I CONFUSED YOUR POST WITH ANOTHER I ANSWERED A FEW MINUTES AGO

WIFE IS THREATENING ME ABOUT WASHING OUR BEAGLE, WHO JUST GOT INTO SOMETHING AWFUL IN THE WOODS A LITTLE WHILE AGO

WORK CALLED AND NEEDED ME, UNTIL I GOT TO STOP SIGN ON MY ROAD, THEN THEY DIDN'T!

THE MEDIC
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 6:50 PM
Tiny
PHTD1990
  • MEMBER
  • 4 POSTS
Lol it happeneds.
Was this
answer
helpful?
Yes
No
Friday, January 2nd, 2015 AT 7:26 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,005 POSTS
I DON'T KNOW WHAT WAS DONE DURING ENGINE SWAP, SO I DON'T KNOW IF THE CODE THING IS STILL-A-WORKIN'

HAVE YOU TRIED TO RETRIEVE CODES? THIS MIGHT CLUE YOU IN TO A DIRECTION TO FOLLOW. THE "GIVEN FLASHES" THEN THE ACTUAL CODE FLASHING MAY CONFUSE YOU AT 1ST, BUDDIES TEND TO HELP FIGURE OUT WHAT IS WHAT!

GET THE NUMBERS, POST THEM, I'LL CONTINUE TO TRY TO ASSIST

I FOUND THIS ONE FOR YOU

http://www.youtube.com/watch?v=p04NPv_gXsI

THERE MAY BE OTHERS THAT 'SPLAINS THIS BETTER, DO A LITTLE YOU TUBE HOMEWORK!

I'M STILL WAITING FOR THE OTHER GUYS TO JUMP IN

THE MEDIC
Was this
answer
helpful?
Yes
No
Saturday, January 3rd, 2015 AT 5:56 PM

Please login or register to post a reply.

Related Engine Stall While Driving Content

How to Read Codes
VIDEO
How to Read Codes
In­struc­tional re­pair video
Engine Stalls While Driving
GUIDE
Engine Stalls While Driving
An en­gine that stalls while dri­ving and then starts back up again, ei­ther im­me­di­ately or af­ter a short time is dif­fer­ent from an en­gine that just wont start or if the...
VIEW MORE