Question about Ford E-350 Super Duty

2 Answers

1990 f-450 super duty tow truck 460 gas stick shift last year engine light coming on random, get back to shop works fine finally stuck on gives code for o-2 sensor lean thnk it was a 42 or 43 replace sensor didn't fix, checked to make sure exhaust pipe port wasn't plugged up got good flow to sensor, checked heater circuit 14.5 volt to heater and ground works great checked signal side blue with purple strip has 4.5 volts sensor unpluged plug it in get .22 volts if you test with orange wire as your ground. test with chasis ground to negative test lead get 4.5 volts ground orang wire to chasis and get .5 volts cant get it to work... truck runs great other wise lots of power, no smoke but seems to have dropped fuel milage exhaust smells bad this year of truck has no cat from the factory and 1 o-2 sensor replaced map sensor hoping it had a problem but didnt seem to fix it

Posted by on

  • chancetowing May 29, 2011

    no exhaust leaks, fuel presure is 40 engine off, 30 engine running, service on engine and filters is new no miles and gets serviced 5k miles constantly, fuel pump dead head at 95psi, both tanks, regulator moves about 5psi with vacume

    truck has more power then the others in the fleet... i am the owner and this one is my personal unit so fuel delivery problem not likely
    spark plugs all burning equal, no matter what i cant seem to get o-2 to change its reading.. can intro propane or pull a vacume line and nothing changes at o-2 reading says lean and running rich at pipe ... very smelly and makes eyes water
    i am stumped on this one

    how can i verify if comp is good... or a wiring problem

    this truck has 210000 miles on it, this sensor thing has been a problem for the last couple years and has finaly failed... had an egr problem too... but it is solved

    no high idle problem like a vacume leak, timing is close to normal.. turned down a couple degrees to keep from pining going up hills... starts every time, runs very smooth..

    if the egr is leaking internally wouldn't it raise the idle... and wouldnt that set a lean code.. far fetched but i am grasping here

    thanks

×

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    President:

    An expert whose answer got voted for 500 times.

  • Master
  • 1,915 Answers

If you are getting a lean code, shouldn't you be looking for a vacuum leak?the lean code you are getting is a symptom,and not the cause if the O2 sensor is working properly-use some throttle body cleaner and spray around hoses, intake gaskets, EGR, etc., you probably have a leak somewhere.

Posted on May 29, 2011

  • mike mountain Jun 06, 2011

    So your O2 sensor won't switch from around .1 to .9, back and forth-it is in open loop, all the time? A good graphing scanner should show a ballpark average of .45 volts if all is well (cen-tech scanner at Harbor Freight is around $120.)...that sounds like the temp sensor is giving a low reading, false or not, to the ECM-and another thing that jumped out at me is the reference voltage should be 5 volts, not 4.5-the heater voltage is a tad on the high side at 14.5 too. So this might be an electrical problem, maybe check grounds and ground locations with an ohm meter. An internal leak of the EGR might be the issue too, that is a little far fetched but since it failed once before might be worth a shot I guess...

×

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Ford Master
  • 1,940 Answers

If your O2 sensor is detecting a lean condition beyond its scope, you could have an exhaust manifold leak, faulty injector, old fuel filter, faulty fuel pressure regulator, or weak fuel pump. It's more than likely just an exhaust manifold leak if the truck runs great, and has plenty of power.

Posted on May 29, 2011

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
New users get 2 Free calls (no credit card required) and instant help on almost anything you can think of (from cars to computers, appliances, handyman, and even pets).
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

2004 ford f250 superduty 6.0L dsl tow haul light flashing and doesnt want to go into reverse


That light means that the shift points have changed on the transmission. This is to get better economy when hauling. If it wont stop flashing then there is a valve in the transmission that is bad or sticking. You will have to have it removed and overhauled..

Dec 12, 2013 | 2003 Ford F350 Super Duty DRW SuperCab

3 Answers

Tail lights on trailer not working f250


did you check the trailer /tow fuse under hood in truck? located lfet side rear near firewall top. should be fuse for towing / trailer.DW Mylin

Dec 01, 2012 | 2008 Ford F 250 Super Duty 4WD

1 Answer

Eng miss and trans problem on 2004 f250 supereduty have run cleaner thru it helps with miss but will come back the tow lite comes on and trans wont shift


For the engine missfire you will need the coil some will show crack on top some internal, and some leak thru the boot, as for the transmission the tempsensor think its towing or a spped sensor which measure turbine, and compares to out put, wont shift your transmission is worn you can probably see it on the fluid conition being burnt(blackish)

May 08, 2011 | 2001 Ford F250 Super Duty Super Cab

2 Answers

How to tow 1999 F250 Super Duty SuperCab XLT 4x4, 7.9 Turbo Diesel V8 engine standerd


you should be able to tow it with the transfer case in the nuetral position.

Jun 09, 2010 | 1999 Ford F250 Regular Cab

1 Answer

Tow/haul light comes on gauge shows HOT


Does the trans fluid have a burnt smell and is it brown or dark brown as opposed to a red wine color? If this is the case then you may have a service issue caused by a clogged trans filter which is what this sounds a great deal like and the sooner you get the truck to the dealer or your mechanic the better as the trans in these are not cheap to rebuild or replace.

Aug 21, 2009 | 2003 Ford F350 Super Duty DRW SuperCab

1 Answer

F-350 Supeer Cab, long-bed, dually, with towing


I don't know how much better gas mileage you will get with a gear change. I don't think it will be worth the cost verses saving a couple mpg. The 5.4L engine is kinda small for this size truck. The better way to go would be a cold air intake and an aftermarket exhaust this will easily give 5-10 mpg increase over stock and won't sacrafice any power when towing

Jun 23, 2009 | 2000 Ford F350 Super Duty Super Cab

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

98 people viewed this question

Ask a Question

Usually answered in minutes!

Top Ford Experts

yadayada
yadayada

Level 3 Expert

76630 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

fordexpert

Level 3 Expert

5537 Answers

Are you a Ford Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...