I have knocking when I try to gun the engine and I have pinging when under load. I've ran several fuel system cleaners, and they seemed to help but its still there. Can this be the symptoms of a bad knock sensor or EGR valve?
please help!

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1998 F150 Triton 5.4L (4x2)
K&N Air Filter
Pioneer 4100 W/remote
2\10" Rockford Fosgate Punch He. RFP4310
CatBack system with Magnaflow system 3" Pipe
3" Performance Acc. Body lift, with lift lips

 

Yup, from what others have said here, it could very well be a faulty EGR valve that's causing the problem.

 

I suggest you do a search on this topic. I have a slight ping in my 98 4.6 that I have been trying to get rid of. I was going to take my EGR valve off and clean also. If you do take if off, don't clean with any solvents. I still think mine is computer related because when the truck is cold, it won't ping. The engine is running rich as it warms up so I know that the computer is leaning out the mixture to much.

 

I had this same problem on my '98 4.6.
It turned out to be the mass airflow sensor. It was replaced and the pinging/rough noise went away.

theone

 

Is there any way to safely clean a MAF Sensor? I have been using a K&N Air Filter for the last 7,500 miles and I am getting a slight miss and a few little crackle/pinging sounds every so often. I also put in some Bosch Platinum +4 spark plugs (not very impressed with them). Anyone else use these plugs?

 

theone, I forgot about the MAF. A dirty MAF could cause the pinging problem too.

As I recall, the way to clean the MAF is to spray Windex on a Q-tip and gently wipe away the dirt from the MAF. Not quite sure why you can't just spray it, but from the cleaning procedures on this board, it appears that you could damage the MAF if you sprayed it.

 

Anyone please help!. Im going to take the EGR valve off soon!

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1998 F150 Triton 5.4L (4x2)
K&N Air Filter
Pioneer 4100 W/remote
2\10" Rockford Fosgate Punch He. RFP4310
CatBack system with Magnaflow system 3" Pipe
3" Performance Acc. Body lift, with lift lips
Xenon HID Super Whites 9007's
Front Clear Corners
Sonnax Line pressure modulator kit model#AX4N

 

I just cleaned my MAF sensor today...
I didn't have driveability issues but I wanted to see if I would notice a difference.

Well, I noticed a real difference in the peppiness of the engine and it seemed to downshift less easily when I gave it pedal. It used to downshift way too easy and wouldn't pull the gear as long with half-throttle type punches before I cleaned it.

Since the Q-Tip that I had was too thick to get to the second element, I thought of using a makeup applicator ($1.50 for a pask of 10)...trimmed widthwise with scissors to fit. For two reasons this made sense to me 1) It was a foam type end rather than a stringy cotton end that left srands of Q-Tip on the element that I had to pull off with tweezers. 2) I was able to trim it to size without it disintegrating as cotton would have. I dipped the end in rubbing alcohol and proceeded to CAREFULLY slide it by both sides of the elements...the fact that it was a spongy type of material it cleaned all sides of the elements just by pushing it by them. Be careful with the deep element not to wedge the applicator and bend it, just be gentle and use lots of light. I also used a jewellers loupe to inspect it after cleaning, followed by blowing it out with 40psi of air. I think I will do this every 10k miles or so.


[This message has been edited by junior (edited 04-07-2001).]