Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

300 I6 Question

Thread Tools
 
Search this Thread
 
Old Oct 14, 2009 | 12:09 PM
  #1  
MustangMatt96GT's Avatar
MustangMatt96GT
Thread Starter
|
Posting Guru
Joined: Nov 2008
Posts: 1,138
Likes: 0
From: Lakewood, Colorado
300 I6 Question

I am looking to buy a 1991 F150 4x4.... The problem with it, is it runs rough at idle and hesitates upon accleration. It has new cap, new rotor, new TPS, new MAP sensor, new fuel filter, and new EGR position sensor.

Will this be an easy and cheap fix? Looking to help my buddy out with getting a truck. What would also could be the issue sensor wise? Anything I should look at to see if ti will be an easy fix.

Thanks Matt
 
Reply
Old Oct 14, 2009 | 12:37 PM
  #2  
quicklook2's Avatar
quicklook2
Post Fiend
Joined: May 2004
Posts: 11,289
Likes: 6
From: Lakewood, Ohio
ignition wires.

plugs.

could be platinum plugs.

crappy/cheap cap and rotor.

wires crossing and misfiring.

dirty fuel injector(s)
 
Reply
Old Oct 14, 2009 | 12:45 PM
  #3  
jimjoebob99's Avatar
jimjoebob99
Senior User
Joined: Jul 2009
Posts: 322
Likes: 1
From: St. Petersburg, FL
Originally Posted by quicklook2
could be platinum plugs.
Not to get off topic but what would the platinum plugs do? I purchased a set but haven't put them in yet. I was planning on doing it today, but I can still take them back.
 
Reply
Old Oct 14, 2009 | 02:09 PM
  #4  
MustangMatt96GT's Avatar
MustangMatt96GT
Thread Starter
|
Posting Guru
Joined: Nov 2008
Posts: 1,138
Likes: 0
From: Lakewood, Colorado
Originally Posted by quicklook2
ignition wires.

plugs.

could be platinum plugs.

crappy/cheap cap and rotor.

wires crossing and misfiring.

dirty fuel injector(s)
It has new wires and plugs too. Forgot to mention that. I am going to go look at it today most likely. It's only 800 bucks with a clean title and only one dent.
 
Reply
Old Oct 14, 2009 | 02:16 PM
  #5  
quicklook2's Avatar
quicklook2
Post Fiend
Joined: May 2004
Posts: 11,289
Likes: 6
From: Lakewood, Ohio
in most of these trucks the plats are a waste of money.

they foul out quickly.

and bosch plats are the worst.

use motorcraft copper plugs for good value and performance.
 
Reply
Old Oct 14, 2009 | 02:17 PM
  #6  
quicklook2's Avatar
quicklook2
Post Fiend
Joined: May 2004
Posts: 11,289
Likes: 6
From: Lakewood, Ohio
Originally Posted by MustangMatt96GT
It has new wires and plugs too. Forgot to mention that. I am going to go look at it today most likely. It's only 800 bucks with a clean title and only one dent.
new anything could still be the problem.


also, read the codes.

even if the light is not on it could have some.
 
Reply
Old Oct 14, 2009 | 02:28 PM
  #7  
MustangMatt96GT's Avatar
MustangMatt96GT
Thread Starter
|
Posting Guru
Joined: Nov 2008
Posts: 1,138
Likes: 0
From: Lakewood, Colorado
Pulling codes for anOBDI sucks, but I do know how to do it. Wish I had a code reader for OBDI
 
Reply
Old Oct 14, 2009 | 02:33 PM
  #8  
quicklook2's Avatar
quicklook2
Post Fiend
Joined: May 2004
Posts: 11,289
Likes: 6
From: Lakewood, Ohio
that is why i have one. :-0
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-1

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-2

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-3

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-4

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-5

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-6

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-7

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-8

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-9

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
Old Oct 14, 2009 | 06:11 PM
  #9  
MustangMatt96GT's Avatar
MustangMatt96GT
Thread Starter
|
Posting Guru
Joined: Nov 2008
Posts: 1,138
Likes: 0
From: Lakewood, Colorado
I sold my escort that I built my code reader for... since that was my only OBDI car, I gave that reader away with it too...
 
Reply
Old Oct 15, 2009 | 07:00 AM
  #10  
TexasGuy001's Avatar
TexasGuy001
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
Originally Posted by jimjoebob99
Not to get off topic but what would the platinum plugs do? I purchased a set but haven't put them in yet. I was planning on doing it today, but I can still take them back.
If the platinum plugs you got are Motorcraft or Autolite then you may have good results. Its hard to say.

I run the MC platinums in mine and have for along time. They last longer in my truck and it runs great.

When in doubt just get the regular Motorcraft coppers.

I will say that all of those plugs like the Bosch platinum and +4 or whatever it is are not worth messing with.
 
Reply
Old Oct 15, 2009 | 07:02 AM
  #11  
TexasGuy001's Avatar
TexasGuy001
Hotshot
20 Year Member
Photogenic
Photoriffic
Liked
Joined: Sep 2001
Posts: 11,958
Likes: 228
Originally Posted by MustangMatt96GT
I am looking to buy a 1991 F150 4x4.... The problem with it, is it runs rough at idle and hesitates upon accleration. It has new cap, new rotor, new TPS, new MAP sensor, new fuel filter, and new EGR position sensor.

Will this be an easy and cheap fix? Looking to help my buddy out with getting a truck. What would also could be the issue sensor wise? Anything I should look at to see if ti will be an easy fix.

Thanks Matt
You can get an OBD I / EEC IV code reader for about 20 bucks or so. I got one made by Equus Innova and it has a digital display. Its alot better than the one I had before where you had to interpret the flashing light.

http://cgi.ebay.com/ebaymotors/Equus...motiveQ5fTools

Its hard to say whats causing it to run bad. Other than whats already been said, it could be bad plug wires or a clogged fuel filter.
 
Reply
Old Oct 15, 2009 | 07:05 AM
  #12  
jimjoebob99's Avatar
jimjoebob99
Senior User
Joined: Jul 2009
Posts: 322
Likes: 1
From: St. Petersburg, FL
They are the Bosch. The guy at the part store had them on sale and talked me into them so I got them. I didn't put them in yet so i'll probably take them back down and trade them for some motorcraft plugs. I put some kind of NGK iridium plugs in my streetbike and it really woke the thing up over stock plugs. I'm not sure what the advantage of the Bosch would be and i've heard a few negative reviews on them so it's best to just get OEM plugs. Thanks!
 
Reply
Old Oct 15, 2009 | 07:20 AM
  #13  
hotrod351's Avatar
hotrod351
Elder User
Joined: Mar 2004
Posts: 759
Likes: 1
From: mohave valley, arizona
the problem could be soooo many things. first id make sure it starts when cold and when warmed up. and i mean make sure the engine is cold, look at the temp. gauge and, or, feel the engine. if it starts right up when cold and when warmed up easy then the other fix might not be that bad to find. also make sure the valve cover doesnt leak, my 90 leaked for years and corroded the wire coating at the back of the engine down on the side behind the distributor where they plug together, it wasnt that hard of a fix but i had to find another wiring loom and cut off a section and solder it on. then again for $800.00 you cant go wrong. ive got a 160,000 miles on my 4.9 and it still runs great and doesnt use a drop of oil, ofcourse i bought mine from the original owner with 103,000 miles on it. there was also a recall on the in tank fuel pumps. both fuel pumps and regulator, i had to do mine myself, the previous owner didnt take care of it. as for plugs i use the autolite copper and havent had any problems. good luck with it.
 
Reply
Old Oct 15, 2009 | 09:38 AM
  #14  
MustangMatt96GT's Avatar
MustangMatt96GT
Thread Starter
|
Posting Guru
Joined: Nov 2008
Posts: 1,138
Likes: 0
From: Lakewood, Colorado
I run motorcraft copper plugs in every engine I build... Even my race motors...

The guy never called back.... but I know the usual stuff to look for, and I have a great knowledge of what will cause an engine to run like this if its all mechanical, and not any elecetrical issue...

I was just hoping it could be a very easy electrical piece that goes bad...

Thanks guys...
 
Reply
Old Oct 15, 2009 | 09:56 AM
  #15  
quicklook2's Avatar
quicklook2
Post Fiend
Joined: May 2004
Posts: 11,289
Likes: 6
From: Lakewood, Ohio
Originally Posted by jimjoebob99
They are the Bosch. The guy at the part store had them on sale and talked me into them so I got them. I didn't put them in yet so i'll probably take them back down and trade them for some motorcraft plugs. I put some kind of NGK iridium plugs in my streetbike and it really woke the thing up over stock plugs. I'm not sure what the advantage of the Bosch would be and i've heard a few negative reviews on them so it's best to just get OEM plugs. Thanks!

ngk v plugs are good for these trucks as well as motorcraft coppers.
 
Reply



All times are GMT -5. The time now is 10:48 AM.

story-0
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-1
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-2
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-3
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-4
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-5
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-6
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-7
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-8
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-9
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE