1997 F150 SC 4X4 4.6L 106,xxx miles

When I bought my truck in July of 2004 it had 46,xxx miles on it. Everything was fine...

Fast forward to the summer of 2006. Around this time I was starting to drive it a lot more... About a hundred miles a day. Now it has about 70,xxx miles on it. This is when it first started having a little trouble. It only happened a few times in the summer of 2006...

After driving for a half an hour or so in afternoon while I am on my way home from work I would get stopped at stop lights and after sitting for a little bit, the truck would idle down and kind of sputter. It only happened a few times and it only did it when the air conditioner was on and it was real hot out side. The check engine light never came on.

It stopped doing it when it got colder outside. The check engine light never came on.

Summer 2007. It happened a lot last summer. Pretty much every time I got stopped at a light it would idle down and sputter. A couple of times it would sputter and choke when I took off from the light. I figured out that if I just turned off the air conditioner at stop lights everything would be fine. So that's what I did. The check engine light never came on.

In September of 2007 with 92,xxx miles on it I took it to a Ford dealership and had the throttle body and induction system cleaned. Also had the fuel filter changed as well as the PCV valve. Didn't fix it. Still had the same problem. So in October of 2007 I took it to another local dealership and had the plugs and wires changed. Opps, they didn't change the wires...

Didn't fix it. Same problem.

I new that I was going to be driving long distances this summer so I took it back to the Ford dealership in Feb. of 2008 and had a Drivability Diagnosis preformed. At that time the cleaned the Mass Air Sensor, had them put on some new wires and the put in a new air filter. The test showed no codes... Still no check engine light. The truck had 98,xxx miles on it.

So now, this summer... Sure enough it started sputtering and idling down when I would stop at a stop light. So I took it to a local shop... Not a Ford dealership. I told the guys what it was doing and told them that I would try to bring it in while it was doing it. Well I was on my way home from Chicago the other day ( 6 hour drive ) and the check engine light finally came on. The only problem with that is...When the check engine light is on, the truck runs fine. I actually sat for 2 minutes with the truck in drive and my foot on the brake, and nothing happened. Usually after 12 seconds at a stop light the truck starts to idle down the starts to sputter.

Anyway, I took it to the shop and they ran a scan on it. George said it said something about the O2 sensor...Bank one, Sensor one... He also checked the fuel pressure and fuel volume.

So, this past Monday, I had the two sensors on the drivers side changed... Didn't fix it. Still does it. Only now it is more intense.

The check engine light came back on, so I took it back up there and George ran another scan on it... This is what is on the paper I got...

DTCs P1131, P1151, P1132 and P1152: Upstream HO2S(S) not switching. DTCs P1130 and P1150: Fuel System Not Switching At Fuel Trim (Rich or Lean)

Diagnostic Trouble Codes (DTCs) P1131 bank 1 (Cylinder 1) and P1151 bank 2 indicate the fuel/air ratio is correcting rich for an overly lean condition. The HO2S voltage is less than 0.45 volt. DTCs P1132 bank 1 (Cylinder 1) and P1152 bank 2 indicate the fuel/air ratio is correcting lean for an overly rich condition. The HO2S voltage is greater than 0.45 volt.
DTCs P1130 and P1150 indicate the fuel control system has reached maximum compensation for a lean or rich condition and the HO2S is not switching.
DTC/HO2S Reference List
--HO2S-11 = DTCs P1131, P1132 and P1130
--HO2S-21 = DTCs P1151, P1152 and P1150

Possible causes:
--Excessive fuel pressure.
--Leaking fuel injector(s).
--Leaking fuel pressure regulator.
--Low fuel pressure or running out of fuel.
--Contaminated fuel injector(s).

Induction System
--Air leaks after the MAF.
--Vacuum leaks (vacuum lines and gaskets).
--Restricted air inlet.
--PCV system.
--Fuel purge system.
--Improperly seated engine oil dipstick.

EGR System
--Leaking gasket.
--Stuck open EGR valve.
--Leaking diaphragm.

Base engine
--Oil overfill.
--Cam timing.
--Cylinder compression.
--Exhaust leaks before or near the HO2Ss.
*Check intake air system for leaks, obstructions and damage.
*Check air cleaner element, air cleaner housing for blockage.
*Verify integrity of the PCV system.
*Check for vacuum leaks.

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I am taking it back in the morning and having it check for vacuum leaks

Also, George says that the computer says that plug 1 has a slight misfire

Has anyone dealt with this problem before?

Thanks Guys.

 

Change the passenger side forward O2 Sensor - It's bad. - Just the forward.

General rule of thumb is to change both forwards at the same time

That's a start .

Plug #1 is the furthest away from the fuel pump. Check your fuel pressure at the rail, the pump may be getting weak.

 

Thanks JBrew.

I had bought two O2 sensors with the intent of the front two being changed... But due to lack of communication, both of the drivers side got changed.

After they check for vacuum leaks, today, I was going to have both O2 sensors changed on the passenger side. I figured for an extra $50 they all would be new.

Thanks again

 

Yea the fronts are more important for engine management (drivability concerns)

The rears are just efficiency checkers (cats)and have specific codes when you step outside of set parameters. You not having issues with those, but it's good to change them all. I would replace with like OEM Bosch parts for the best outcome.

The Stock OEM O2's are a bit expensive, I've tried cheaper Borg/Warner's before and went from 16 mpg to 9 mpg - Yea, so I switched back to OEM's pronto.

Don't forget to the fuel pressure/ w/ #1 missing (might be to lean due to the pump/regulator/return line/buggy relay - One way you can tell a relays bad if it's hot while she's running.

What plugs are you running?

 

Red~97~F150~4x4,

Did you ever resolve your rough idle at traffic lights? I am having the exact same problem with my 97 f150 4.2L as well. Any help would be great...