I am new here and have a couple of trouble shooting questions i need help with.
First off, In the morning when i start my car and start to drive down the road before it is all the way warmed up if i give it too much gas it will sound like it is backfiring. This also happens after i have been to the car wash. I wash it with the hood down so there shouldnt be any water getting in the dist cap. I have changed the cap and plugs and wires to all new. i cant figure this out.
I also have a weird rythmatic vibration i can feel that seems to be coming from the trans or driveshaft at diff rpms. Most noticably at 2,000 in 5th gear.
Here is a list of mods to my car. 1993 LX 5.0 with Griffin 2 row alum radiator,balck magic electric fan,undrive pulleys for crank and water pump,BBK castor camber plates,MSD,Crane coil,1 1/2" unequal length shorty headers,off-road X-pipe,flowmaster american thunder cat back,adjustable fuel pressure regulator,cobra intake,C & L 76mm mas with inlet tube,moroso cold air system,motorsport 65mm T.B.,air cond eliminator pulley kit,180 degree therm,1982 mustang heads with 3 angle valve job ported and shaved with hight life springs and rooler rockers,trick flow alum valve covers,manual adjustable clutch quadrant, motorsport king cobra clutch,sub frame connectors, pro 5.0 shifter,ford motorsport alum driveshaft,lakewood driveshaft safety loop,mega-bite jr lower conrol arms,urethane trans mount and cross member bushings,rear end girdle,stainless steel brake lines, cross drilled rotors. The cam is stock and so is the rest of the block.
Now it used to run great and smooth till after the head install. This is when the back firing started. once the car is warmed up it is fine. If i wash it I must drive it till the back firimg stops also.
Any suggestions would be greatly apprciated and helpful. Thanks.
