Whats causing this?

[MY 85 GT]

I just noticed this the other day only happening on 1 side and only in this spot....its dis-coloring...I have no idea whats causing this..

http://i44.photobucket.com/albums/f19/myhemi/DSC00042.jpg


http://i44.photobucket.com/albums/f19/myhemi/DSC00041.jpg

 

[85_SS_302_Coupe]

Well, assuming you're not running lean on that side, it's probably just a spot where there isn't enough coating and they've started to rust early. Just to be safe, go out and drive your car for about 1/4 mile at 35mph, and shut the car off while going 35 (don't let it come down to an idle). Be sure to be on a back road where it's safe to do since you'll lose power steering and brakes. Then, pull the plugs from the side of the engine that's rusting and see if they're white looking. That'll tell you if they're lean or not.

 

[MY 85 GT]

Well, assuming you're not running lean on that side, it's probably just a spot where there isn't enough coating and they've started to rust early. Just to be safe, go out and drive your car for about 1/4 mile at 35mph, and shut the car off while going 35 (don't let it come down to an idle). Be sure to be on a back road where it's safe to do since you'll lose power steering and brakes. Then, pull the plugs from the side of the engine that's rusting and see if they're white looking. That'll tell you if they're lean or not.

Thats the side i was told that runs leaner on a 5.0...thats were i have my Air fuel gauge the o2 sensor is in the bung just in front of that spot...By the air fuel gauge it doesnt seem to be running lean...I did pull the plugs out the other day to inspect them not after doing a 35 mph pass...They always come out clean and like the day i put them in...I still wonder by having that the stock intake on there with no EGR valve spacer an no emissons anymore if im screwing up something...I mean if you take my carb off the gasket has a hole burnt in it...and that port if full of black caked up carbon....not a pretty sight....I have to get a intake ont here just didnt have the chance..hope im not hurting anything.....