Rough at idle
Senior Member
Joined: Aug 2008
Posts: 1,499
Likes: 2
From: Liberty, MO
Remember to disconnect the negative battery cable while you swap the sensor. That will clear the codes while you do the swap.
Also be prepared for the chance that it doesn't help - you valve may move, but it might not be seating properly, sticking, etc.
Only time will tell - good luck!
Also be prepared for the chance that it doesn't help - you valve may move, but it might not be seating properly, sticking, etc.
Only time will tell - good luck!
Junior Member
Joined: Aug 2010
Posts: 20
Likes: 0
You should give up i have owned three 4.9 f150 and they all have the misfire thats why they dont make the motor anymore... you will never find the problem... its the luck of finding one that does not have that problem ,do an extensive test drive before you buy and if you can find one that does not miss buy it ...wait i will buy it from you
I LOVE OLD FORD'S
Joined: Nov 2010
Posts: 495
Likes: 0
From: daphne al
Weak Battery(?)
A weak battery caused my 87 4.9L EFI to idle rough and go dead at stop signs.
I charged my battery and when it idled normally and didn't choke down at stop signs,
I replaced the battery and I've had no more problems with it idling rough.
FYI - An alternator will work overtime trying to charge a battery with a bad-cell
and will burn itself out prematurely.
April 2010 TOTM Winner
Joined: Jan 2010
Posts: 515
Likes: 3
From: Panama City, FL
You should give up i have owned three 4.9 f150 and they all have the misfire thats why they dont make the motor anymore... you will never find the problem... its the luck of finding one that does not have that problem ,do an extensive test drive before you buy and if you can find one that does not miss buy it ...wait i will buy it from you
or
You never spent the money to repair the problem correctly.
I've had five 4.9L / 300ci engines from 1976 to 87 and none had a misfire that you are speaking about.
The 1967-86 300ci had a 1 barrel carburetor and that was too small,
other than that, the 4.9L is one of the toughest Ford engines ever built.
Yeah, not much power on the top end, but a pulling motor.
The 4.9L is installed in UPS Trucks and Ford Dump Trucks up to 18K GVWR.
And it's not the best engine for gas mileage either,
because it is a long stroke, low RPM engine.
It's too bad you found three worn out 4.9L engines or someone did not know how to properly fix the problem you had.
Nuff said...
Thread Starter
Senior Member
Joined: Nov 2010
Posts: 208
Likes: 0
From: Toms River,NJ
YOU BOUGHT THREE ALREADY WORN OUT ENGINES!
or
You never spent the money to repair the problem correctly.
I've had five 4.9L / 300ci engines from 1976 to 87 and none had a misfire that you are speaking about.
The 1967-86 300ci had a 1 barrel carburetor and that was too small,
other than that, the 4.9L is one of the toughest Ford engines ever built.
Yeah, not much power on the top end, but a pulling motor.
The 4.9L is installed in UPS Trucks and Ford Dump Trucks up to 18K GVWR.
And it's not the best engine for gas mileage either,
because it is a long stroke, low RPM engine.
It's too bad you found three worn out 4.9L engines or someone did not know how to properly fix the problem you had.
Nuff said...
or
You never spent the money to repair the problem correctly.
I've had five 4.9L / 300ci engines from 1976 to 87 and none had a misfire that you are speaking about.
The 1967-86 300ci had a 1 barrel carburetor and that was too small,
other than that, the 4.9L is one of the toughest Ford engines ever built.
Yeah, not much power on the top end, but a pulling motor.
The 4.9L is installed in UPS Trucks and Ford Dump Trucks up to 18K GVWR.
And it's not the best engine for gas mileage either,
because it is a long stroke, low RPM engine.
It's too bad you found three worn out 4.9L engines or someone did not know how to properly fix the problem you had.
Nuff said...
ha burned..yeh iam sure ill find the problem