I have a 99 xlt 4.6l. The engine runs good but it occasionally pings when its under a load or going up hill when i get on the gas a bit comming of idle. I've cleaned the EGR passage, throttle body, and IAC. Are there any common problems with these motors that I should check about this?

 

see any thread with seafoam mentioned in it

 

Whats the deal with the seafoam craze on here? I don't really like the idea of running a bunch of cleaner through the motor like that. Plus usually normal carbon build up isn't enough to cause pinging. Its usually timing, air, or fuel issues. But thanks for the reply.

 

I think you may find there is a difference between Pre-Ignition & Detonation.

Detonation will cause severe damage to your motor & lead to failure.
But your not running a supercharger so it may be just Pre-ignition.


If in doubt seek expert advise

 

Well before you do all that try the most simple thing. Put a thing of gas treatment in if you haven't already and run your tank almost empty. There is stuff to put in if you picked up a tank of bad gas. Sounds almost like a tank of bad gas and it will continue through all your fill ups if you dont run it dry b/c the water will sit on top and condensate on the top. Try not run gas like sheetz and giant and places like that. Try to use a HESS or Sunoco, or even texaco or whatever texaco is now i guess Amoco or even better Shell. Some cars dont like to run on low grade stuff ( i dont know if you do or not) try 89. I dont know i hope it helps if you haven't tried this already. Hope it might work out for ya.