Go Back   Ford Truck Enthusiasts Forums > Small Chassis Trucks > Explorer, Sport Trac, Mountaineer & Aviator
Sign in using an external account
Register Forgot Password?


Explorer, Sport Trac, Mountaineer & Aviator 1991-1994, 1995-2001, 2002-2005, 2006-2010 Ford Explorer

Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
LinkBack Thread Tools Search this Thread
  #1 (permalink)  
Old 09-14-2004, 02:24 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
98 Explorer P0171 P0174...

I've found this problem posted a lot but haven't found a solution. I have a 1998 Explorer Sport, 4.0 EFI (Not SOHC). It has 106,000 miles and runs perfectly, cold and hot.

The MIL light comes on all the time. I got a codes scanner and it shows P0171 and P0174. I clear the codes and can go from a couple hours to a couple weeks before the codes flag the light on again.

I took it in for a required smog test (California) and the emissions all pass but the car fails only because all the monitors have not run. I check the monitors every time I start it up to see if they have cleared. This last time all cleared except the catalyst monitor when the light came on again. The P0171 and P0174 codes stayed pending a few days before the check engine light actually came on.

I have cleaned the engine and examined all the vacuum hoses with no luck. I checked and cleaned the MAF sensor as some suggested with no luck. I checked and cleaned the PCV valve and hose with no luck. I've sprayed carb cleaner and starting fluid around the lower intake manifold but didn't notice any change.

I'm not sure how to diagnose the O2 sensors. There is no surging at idle, cold is around 1100 RPM and hot around 800, both are steady. I don't have the cash to just replace them without being fairly certain what the problem is.

I just need to get it past the smog test. Help?
Reply With Quote
  #2 (permalink)  
Old 09-21-2004, 12:10 AM
automatic2 automatic2 is offline
New User
 
Join Date: Sep 2004
Posts: 4
automatic2 is starting off with a positive reputation.
too lean

I visited my dealer last month with the same problem and he quoted $1000 to repair. I took it home and replaced the upper intake manifold gaskets (o rings), injector o-rings and egr gasket. Runs great, no errors, and about 10% better gas milage. All for a total of $300 plus my labour. That includes the OBDII tester I have now added to my toolbox. (4L pushrod)
Reply With Quote
  #3 (permalink)  
Old 09-21-2004, 01:28 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
Thanks for the reply. I already have the code reader so hopefully that will cut my cost down. I've replaced the PCV valve and air/gas filters, re-cleaned the MAF, to no avail. I'll try the gaskets this weekend. Any tips on changing them?

(I just ran over to AutoZone. They only show throttle body manifold gaskets, no upper manifold. They don't list any o-rings for the injectors. I couldn't get over to Napa due to roadblocks for some reason. Will try tomorrow or the Ford dealership.)

Last edited by canyonbreeze; 09-21-2004 at 02:01 PM.
Reply With Quote
  #4 (permalink)  
Old 09-21-2004, 04:09 PM
automatic2 automatic2 is offline
New User
 
Join Date: Sep 2004
Posts: 4
automatic2 is starting off with a positive reputation.
It's embarassing but I'll confess, when things went back together I mixed plug wires 5&6. Look carefully at the numbering cause it just doesn't follow any logic. Loosen your a/c compressor to give you room to thread the egr pipe when lifting the upper manifold (runners) off. The runners require 3 seals (paired). It takes a good steady pull to lift the fuel rail off the injectors. If I recall I did end up using a pry to assist. Much easier on assembly side. I used some petroleum jelly on the injector O rings (2 for each injector) which helped. The rail to lower manifold gasket is a thich heat shield unit, easily placed. If I had worked steady it probably would have been a 4 hour job. Good luck.
Reply With Quote
  #5 (permalink)  
Old 09-23-2004, 12:07 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
The parts stores list a lower manifold gasket and a fuel rail to plenum gasket. Is the fuel rail to plenum gasket the one you are refering to as the upper gasket? Also, no one lists injector o-rings. Did you have to go to the dealership for that? (There is not a Ford dealership near me so I haven't checked there).
Reply With Quote
  #6 (permalink)  
Old 09-23-2004, 12:59 PM
automatic2 automatic2 is offline
New User
 
Join Date: Sep 2004
Posts: 4
automatic2 is starting off with a positive reputation.
You'll need;

3- F57Z-9E436-AA
1- F6TZ-9E436-C
1- CG-682
2- CM-4717 this is the injector seals and comes as 10 to a bag. if they don't have a couple loose ones kicking around, you'll need 2 bags.

These were the parts numbers for my '98 exoplorer, 4w, 4L pushrod.
Reply With Quote
  #7 (permalink)  
Old 09-23-2004, 02:13 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
Found a Ford dealer not too far away, all parts in stock. Total $75.35. Will post back after this weekend. Muchisimos gracias.
Reply With Quote
  #8 (permalink)  
Old 09-27-2004, 03:51 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
I replaced all the above parts yesterday. Didn't find a need to move the a/c compressor as suggested. Lost about one hour due to my clumsy hands dropping a nut into the intake manifold. This wasn't all that bad as my wife was eventually able to fish it out with a couple steel welding rods bent as hooks. Watching her, an ex-professional dancer, hunched up under the hood in her shorts for about 40 minutes made me feel life is good.

Got it all back together and let it idle about 10 minutes. Went to road test and it dies about halfway down the block. Wouldn't restart so I looked under the hood, all seems ok. Then it restarts fine after about 5 minutes. Did about 10 trips around the block and then the 40+ freeway miles to work this morning.

No errors flagged yet. Will have to see if all the monitor flags in the driving cycle clear without any errors. This can take a few days.

There is a pronounced howl sometimes now that stops when I tap the gas pedal. From other posts I think this may be the Idle Air Control (IAC). I did remove and clean this when changing the gaskets. Is this noise a problem or just an annoyance?

Thanks again and will update in a few days.
Reply With Quote
  #9 (permalink)  
Old 09-28-2004, 12:44 AM
automatic2 automatic2 is offline
New User
 
Join Date: Sep 2004
Posts: 4
automatic2 is starting off with a positive reputation.
I had to fish out the plastic retainer for one of the injectors from inside the manifold. Not sure about the howl?
Reply With Quote
  #10 (permalink)  
Old 09-28-2004, 12:31 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
Didn't fix it. Check engine light came back on, same codes. Maybe the IAC?
Reply With Quote
  #11 (permalink)  
Old 09-30-2004, 01:40 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
Changed the IAC valve. The 'howling' went away and there is a slight but noticable improvement in acceleration.

But the original problem of the P0171 & P0174 codes is still there. In fact it seems a bit worse as the flag on within a half hour to an hour now instead of a few days.

But now I am out of money until I get paid in a few weeks. I'll request an additional time extension from the DMV and get back on it then. Any diagnostic help in the meantime is muy apreciado.
Reply With Quote
  #12 (permalink)  
Old 10-19-2004, 02:36 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
Let it go without resetting the codes for a couple weeks as I had no money to do anything. Went to clean the MAF again, this time under a microscope. It looks very clean.

When putting it back I notice the oil filler cap is gone. It was there when I changed all the gaskets and the IAC. Bought a new one for $5 and am hoping that maybe this little part will fix the issue. There is an air tube from the oil filler pipe to the air intake just after the MAF, an obvious air leak if the cap wasn't sealing good, more obvious with the cap gone.

Reset the codes and will wait and see. The C and EV never cleared in the last few weeks. When there are codes flagged and the MIL on, does the drive cycle stop doing the checks?
Reply With Quote
  #13 (permalink)  
Old 11-01-2004, 05:32 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
Almost 2 weeks now and no codes are logged. The drive cycle tests have cleared except for the C which is still blinking. I believe that's a catalyst test. Any clues why that isn't clearing?
Reply With Quote
  #14 (permalink)  
Old 11-05-2004, 01:07 PM
canyonbreeze canyonbreeze is offline
New User
 
Join Date: Sep 2004
Posts: 19
canyonbreeze is starting off with a positive reputation.
See the resolution in the thread at...

http://www.ford-trucks.com/forums/sh...52#post2098652

Catalyst test still hasn't completed, but wasn't necessary to get passed California smog test.
Reply With Quote
  #15 (permalink)  
Old 07-23-2009, 06:21 PM
bodyman91774 bodyman91774 is offline
New User
 
Join Date: Jul 2009
Posts: 1
bodyman91774 is starting off with a positive reputation.
hi i also have a 1998 ford explorer with the same codes. changed everything but the iac valve. what does IAC stand for? would like to resolve my problem and hope changing that will do it. thanks.
Reply With Quote
Old 07-23-2009, 06:21 PM
Reply

Go Back   Ford Truck Enthusiasts Forums > Small Chassis Trucks > Explorer, Sport Trac, Mountaineer & Aviator

Tags
01, 97, 98, ac, air, cleaner, explorer, ford, howling, iac, manifold, p0171, p0174, po171, removing, sport, upper

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On
Forum Jump



All times are GMT -5. The time now is 11:58 PM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.5.2 ©2010, Crawlability, Inc.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup