There have been numerous discussions here and elsewhere about the pinging problems many Explorers have. My 94 had the problem and it wasn't solved by cleaning the MAF sensor or some of the other suggestions that have helped others. The only thing that would stop the occasional pinging was higher octane gas. For the most part I ran regular 87 octane except when pulling loads or on trips to the mountains, since the high test is so expensive. For normal driving I would just keep my foot out of it to eliminate or reduce the problem.

My pinging is now gone so I figured I'd share what happened. I realize it may not work for everyone but here it is.

I recently began experiencing a hesitation when accelerating. It was almost like someone would squeeze the fuel line for a second. This vehicle never did that before and ran great (except for the ping) so it was all the more noticeable and it quickly got worse over the course of a week.

I brought it to a shop I've dealt with for years and they put it on the computer. Apparently a sensor failed which caused other equipment to go bad. In my case the MASS air flow was shorted and the MASS airflow sensor and IAC were bad. The EGR system was plugged with carbon. I guess that isn't too surprising with 195,000 miles on the odometer. The following is the list of items that were replaced. It cost me $734.00 because these sensors are not cheap. Most of the cost was for parts.

Because of the expense it's obvious that the solution isn't to replace all the parts unless it's necessary. The good news is the computer may be able to read your equipment as failing before it does more damage like mine did.

Here is what I replaced:

OEM DPFE sensor for EGR valve
OEM IAC motor (idle air control)
OEM air flow meter
OEM EGR valve
OEM vacuum control valve
MASS air gasket
EGR valve and sensors (also cleaned ports)

I hope this helps someone to fix the problem before the cost skyrockets.

SGF

Originally posted by SGF

OEM air flow meter
OEM vacuum control valve


Thanks for the info SGF. But I am trying to learn...I know about most of the parts you listed. But what are these two?

Is "air flow meter" then mass air sensor filament/electronic sensor?

And what/where is the "vacuum control valve"?

Thanks...

how much did it all cost you and did you do it your self?

sorry just read the $734 wow thats alot

It averages out to like $80 per part + labor charges, so that seems within reason I guess.

Does she run alot better now?

To answer your questions, it runs absolutely great now. Almost $600 was for parts. The shop said that with this computer controlled electronic components it isn't uncommon for the failure of one item to adversely affect the others and cause damage. Although they are independent components they work together and are affected by each other. I'm sure the high mileage on my Explorer contributed to this since the components are aging, etc.

Believe me I about passed out when I heard the bill. I was thinking "gee I hope it doesn't hit $200"...yea right! It is pretty shocking how expensive these items are but most have to come from the dealer so you know it'll hurt your wallet.

As far as answering where the components are I'll have to defer to someone else. I have swapped motors and transmissions, pulled heads, etc. etc. but when it comes to these sensors or the vacuum control systems I'm lost.

SGF