Just experienced a rough idle and eng. light coming on. Sprayed the MAF with CRC cleaner and all well. Shortly thereafter a rough idle again w/ light back on. Cleaned the MAF again and no help. Had codes of P0171, P0172 and P0133.

These are now gone and have P01131 and it still idles a bit rough. Pulled plugs on bank 1 and they all looked good. PCV looks very clean and rattles.

Very frustrated, any suggestions??

Thanks in advance.

 

Replace your forward O2 sensors/ check the harness around the O2's as well.

Replace w/only Bosch OEM Sensors for best results and change both at the same time w/battery disconnected.

Your correct part number is on the sensor itself. If you need to know where to get these online , just ask.

 

Didn't make it to the O2 sensors yet, but have more symptoms to report. The rough idle now only appears after I power up a hill and stop shortly thereafter. It stumbles a bit and then when I give 'er it'll go away. The truck will also faulter at highway cruising speeds occaisonally.

The throttle body is rather dirty/oily and I wiped it clean with a dry rag. No solvents as a result of a "protective coating" per Haynes. Checked TPS and that seemed to work fine, but Haynes manual has some errors in it (pin-out doesn't agree and the volts are opposite for open and closed throttle). Clarification would be nice. Might try surfing for that tonight. Also checked the IAC, MAF DPFE all checked out. I sprayed down manifold with carb cleaner to check for intake leaks, nothing. Also used a stethoscope to check all injectors, clicking fine. Removed all COPs and plugs, cleaned, dielectric grease and returned. Ran 4 oz Seafoam through PCV, let sit and started. Now I'm running a pint of Seafoam through with 8 gallons of fuel.

Fuel filters and O2 seems to be all that remains. I'm thinking I should start with the fuel filter because the O2's can be buggers to get out.

Your thoughts?

 

You might need plugs. Maybe a coil is weak but jbrew says you need o2 sensors so you better do that first.. That might be what the code is.

 

have you washed your engine lately? sometimes if you wash your engine ford has a stupid cop system and the water penetrates in and fouls up the coil it sucks ive spent over 1000 bucks just from washing my engine

 

Thoughts ? I thinking you should of just done what I told yuh and the trouble codes would disappear. I think you should have left that Seafoam on the shelf at the store, specially when your having O2 problems - Choking them with smoke will make matter worse.. Replace what's broke and your truck will thank you. Your prolly starting to foul the plugs now.


Look at the codes - You have Lean/Rich on the same sensor - That's funny , you don't see that happen to often, but when you do ....... - 71,72 = B1SI Positive/B1S1 Negative ~ Followed up by 133 = O2 Circuit High Voltage (Bank 1, Sensor 1) ; Also - P1131 Lack Of HO2S11 Switch - Sensor Indicates Lean.

It's pretty safe to say the Passenger side O2 (B1S1) is toast. It's best to change both forward sensors at the same time to maintain system integrity. Specially those sensors.

 

Gosh JBrew, you sound pretty confident. I guess with 9,124 posts to date it's a pretty good bet you're right. So I picked up a pair of Bosch O2's tonight and was able to get the driver side O2 sensor in tonight, but could not get my hands to the pass. side O2 unit. Not exactly sure how I'm going to get a O2 socket on this one, but will try to tackle it again tomorrow night.

P.S. The engine has not been washed.

 

Well yea - All the codes you posted point to one sensor. Also - The sensor is sending contradicting information. That's what gives it away. The wires/connector/harness for the bad sensor (Passenger side) is in a bad spot as-well .

If you have any coolant leaks from behind the water pump all the way up to your heater core lines - it all ends up in one place = Behind the passenger side head /hits the O2 harness on it's way to the starter before it puddles on the ground under the truck. So watch for that as-well.

You need the right tool for that side -



Good Luck

 

I have that tool, worked great on the driver side, but not pass. side. I heated up the bung a bit and then she popped with a long open end. A bit of antiseize and she went in okay. Not a lot of room to work and I couldn't get off my tranny dipstick tube which was in the way big time.

At any rate I took her for a quick spin and the performance was noticeably different just getting out the drive way. I warmed it up and loaded her up on hills and all seems well. YOU ROCK! Thanks a bunch for the pointers. I owe you a cold one.

What are your thoughts on cleaning my thottle body?

 

Glad it worked out

The TB - Yea, that's always a good idea.- The elbow and ports as well

 

Can I ask a new question here, my truck is saying I have O2 sensor problems. Bank 1, sensor 1 and 2. Jbrew you recommended getting Bosch. Where can I get them online? I have a 1997 F150 with the 5.4L engine.

 

Yea, don't get anything but these. I learned the hard way. Get these and you'll have NO problems.


http://www.autopartswarehouse.com/se...20Ford%20F-150

 

Jbrew

Where did you get the tool from?

 

I picked up the tool at Autozone for $9.99 and the front o2's were $46.99 i followed the sticky on the change out and it went like a charm. The only real problem was when i changed mine out saturday it was 108 deg outside and i only had 2 box fans in the garage. Took a few beers to get hydrated again. I did notice on the passenger side connector to the sensor had some slight discoloration. The cel code thrown was a p0135 that may have had something to do with that.

 

Had the same problem on my 2002 Supercrew at 88,000 miles. Ended up being the #8 coil. Had it changed out and the truck runs like new. Truck would idle rough and hesitate horribly as if it had water in the fuel lines. This was the problem for me, looks like it could be any number of things judging by the posts on here, but this is where I would start.