Code p0174. Smooth Running, Great MPG

[capleton456]

Okay, my 1999 Explorer Sport OHV threw a code p0174 a week before the state inspections. It has 169,000 miles on it and it runs smooth with no vibrations plus it needs only one full tank of gas for the week. Usually I would not post this as other posts seem to have this error code but the only problems I have is that it takes a nice crank to startup and when the engine is fully warmed up and in park the tach needle swings down to 500 rpm and then the engine revs it back up to 1000 rpm, also When I start it up in the mornings I have to let it run for 30 seconds before putting t into drive or it will shut off. I am going to try to clean the maf sensor tomorrow but would like anyones opinion since I have no hesitations and such.

 

[dynamite196]

check the idle air control sensor too (the one on the intake manifold)

 

[capleton456]

Can I clean that one or do I have to replace it?

 

[dynamite196]

you can clean it, it's the silver one with the hoses going to it

 

[capleton456]

If it is the device with the black cap on top of the OHV engine then it looks new. I have had the truck for 2 months and although the engine is dirty, the device on the top center of the engine, here is a picture from ebay. Mine is shiny and new looking.

Here is the link i case it does not work
http://cgi.ebay.com/ebaymotors/Ford...018QQitemZ280042274650QQrdZ1QQsspagenameZWDVW

 

[ma96782]

So, what is code 0174??

If memory serves me.......or search. (bank#2 lean)

http://www.explorerforum.com/forums/showthread.php?t=150571&highlight=0174

BTW.....SEARCH IS A GOLD MINE......there are many threads......sometimes this works and sometimes that works......the codes don't just mean, "change this and all will be well." A little brain power may at times be needed, to figure it out.

But IMHO, just from what your'e saying..........I'd be suspecting that you had a fuel problem (or sensor issue).....duh.

So, is the sensor bad and throwing a code.......or is the sensor good and telling you that something is causing the lean condition. That being said........changing a sensor is easier than changing a fuel pump. But.....may not be needed.

Wouldn't it be nice....if we could remove them, take them down to the auto parts place and test them (like a bench test)? I hear that IF one was to connect a SCANNER, one could tell (alot more)........Hummm. Maybe a good investment?

OK, how about testing the fuel pressure. BTW, what is the condition of the fuel filter (changed it recently?) And what about the fuel pump and regulator? So, a test could be in order:

Explorer Fuel Pressure Test

http://www.explorerforum.com/forums/showthread.php?t=142801


Aloha, Mark

PS.....While cleaning the MAF....why not do the IAC too.......replace the pcv & air filter (if it wasn't done recently).

 

[capleton456]

Yes I considered all that, I just thought it strange that I was getting such good performance when the case is usually hesitation, poor fuel economy etc:

 

[stang99x]

You'll get great performance on a lean code. You'll also get a code, and risk detonation. Running rich runs like crap, running lean runs better than ever, get better mileage, and performs best, but also risks the most. Thats one reason the forced induction crowd has to monitor their A/F ratios so often. You probably have a vacuum leak somewhere. Start by checking all the hoses and lines. I think you'll find it there.

 

[capleton456]

Took off the maf sensor today and the wires are covered in a layer of black dust. Unfortunately, the sensor has some sort of plastic cover on it that is different than normal and makes it harder to reach the wires. SO I am just going to change it and the fuel filter and hope that solves it.

 

[capleton456]

I took my explorer to my mechanic for a fuel pressure test and another code read and he told me that it was not my maf sensor but both of my o2 sensors before before the catalytic converters needed changing. I want to know if I can trust his opinion or go with the maf sensor.

 

[timleedude]

As for your mechanic, how did you get to know this mechanic? Did someone refer him to you? Did he do previous repairs for you? Does he seem like a reliable mechanic? etc? Could be sensors.. If it's been a while since those sensors have been changed... then might be a good maintenance/fix gamble.

-Tim

 

[ma96782]

not my maf sensor but both of my o2 sensors before before the catalytic converters needed changing.

Someone once mentioned that you could switch left and right bank O2 sensors.........in order to test.........see IF you get the same code...........assuming that one O2 was working and one wasn't...........the code should jump to the other bank.

Aloha, Mark

 

[capleton456]

As for your mechanic, how did you get to know this mechanic? Did someone refer him to you? Did he do previous repairs for you? Does he seem like a reliable mechanic? etc? Could be sensors.. If it's been a while since those sensors have been changed... then might be a good maintenance/fix gamble.

-Tim

I've known him for years. He did an engine overhaul for me and he will do the work free if I cannot pay him for awhile. His work has been pretty good too, but I just wanted a second opinion. Also, should I use oem parts or are there better brands out there?

 

[timleedude]

Then sounds like I would trust the mechanic's advice. Wish I could find a good mechanic like that.. All of the ones here are too expensive and/or a ripoff.
I would go for the OEM stuff if you can... If the aftermarket cost alot less, then go for that... Make sure the aftermarket stuff is the same/similar as OEM if you use them.
Good Luck
-Tim

 

[bigtigga84]

i had the same codes go off, had the maf cleaned, vaccume lines all checked. all kinds of fun stuff. in the end it was the upper ait intake manifold gasket. so after having that replaced, having the cam shaft tensioner kit replaced cuz it sounded like somebody was getting slapped when i started my truck, and 700 bucks later, no more code. just to give you a worse case senario. also had it done at the dealer so that probably didn't help the cost any.

 

[capleton456]

Final post to this thread. My mechanic cleared the codes with the understanding that I would bring it back on the weekends to fix. It needed to pass the fitness test so I took a shot and brought it in. It passed fully and the check engine light will not come back on. I'm still going to change the sensors though and ask my mechanic if he can do the the two suspension per wheel mod that I saw on this website.