i've read on many responses to threads that the egr and maf parts need to be cleaned and or replaced .i have 145000 mile on my 4.2 97and one of these animals just might be part of my rough idle problem. where are they located and how do u replace them??????

 

is located on the left half of your filter box...you can get an electronics cleaner for that and spray both sides of it.....the EGR is the circuler object located just behind the throttle body area on the drivers side of the engine..this is a non-servicable item ...you might check the hose coming from the PCV to the rear of the plenium for a crack thats allowing air in

 

thanks tex i'll try cleaning the maf . my next stop will probably be the ford dealer . i keep getting a misfire code . i think i've got injector problems.... i think you mentioned once before you live in the dallas area if so do you recomend a shop for tht kind of work. tommy m.

 

Do you have the code number ?

Maybe a quick look around with the code number, and you'll have some things to check before you pay the dealer.

Just a thought, post the code and myself on another should be able to give you the info to look at.

Just an offer of help, it may not be as bad as you think it is.

 

thanks for the offer sccully.
the code showing up now is #302. misfire on plug #2. the plugs are all new as of 4days ago. wires are also new. several weeks ago the codes indicated also lean on banks #1 &#2. i fixed several vacuum leaks and now the only code is 302. i have also replaced the idle control valveand reset the pcm. the coil pack seems to be firing a spark on the #2 wire as i've pulled the wire and there seems to be a good spark at the pack. all i can think of now is an injector problem. the truck runs fine once you give it the gas. the idle is very rough though. i also have run several types of injector cleaners through it and they haven't helped. thanks, tommy m.

 

Here is the manual excerpt from P0301 to P0310

Sorry but they do not seem to be of any help with this, beyond you might have saved some of the stuff you did.
Maybe your injector is beyond the help of injector cleaner. I hope not though.

DTC
P0301 through P0310 Misfire Detection Monitor
Description
The misfire detection monitor is designed to monitor engine misfire and identify the specific cylinder in which the misfire has occurred. Misfire is defined as lack of combustion in a cylinder due to absence of spark, poor fuel metering, poor compression, or any other cause.

Possible Causes
-Ignition system
-Fuel injectors Running out of fuel
-EVAP canister purge valve
-Fuel pressure
-Evaporative emission system
-Base engine

Diagnostic Aides
The MIL will blink once per second when a misfire is detected severe enough to cause catalyst damage. If the MIL is on steady state, due to a misfire, this will indicate the threshold for emissions was exceeded and cause the vehicle to fail an inspection and maintenance tailpipe test.

The codes for the P0171 ( you ref to the additional code you got ), just so you have them to see if anything is common between the 2.

DTC
P0171 - System to Lean (Bank 1).
Description
The Adaptive Fuel Strategy continuously monitors the fuel delivery hardware. The test fails when the adaptive fuel tables reach a lean calibrated limit.
Possible Causes
For lean and rich DTCs
-Fuel system
-Excessive fuel Pressure
-Leaking /contaminated fuel injectors.
-Leaking fuel pressure regulator.
-Low fuel pressure or running out of Fuel
-Vapor recovery
Induction system:
-Air leaks after The MAF
-Vacuum Leaks.
-PCV system.
-Improperly seated engine oil dipstick.
EGR system:
-Leaking gasket.
-Stuck EGR valve.
-Leaking diaphragm or EVR.
Base Engine:
-Oil overfill.
-Cam timing.
-Cylinder compression.
-Exhaust leaks before or near the HO2Ss.