I have a 93 mustang that I pulled stock engine from and put in a fresh 306. It has elderbrock heads (gone thru by engine shop), trick flow upper and lower intake, ford racing 24lb injectors, crower cam, msd dist, ford racing wires. so pretty much everything is new. I have been building the engine for 5 years and finally put it in on Saturday. Fired it up that afternoon for the first time (after getting timing close) and it was skipping and popping sounding like a hit and miss engine. A friend came by today and set the timing the best he could with it running the way it is and it sounds like it is running on 6 cylinders. Pulled plugs and they were wet, and sprayed water on each tube on headers and all were hot except numbers 5 and 6. Does anyone have any suggestions at all? I am just running out of ideas and have no clue were to go next. Thank you in advance.

 

I forgot to add that when it WAS running that the rpm's would be around 800, then jump to 2200 for a second then ease back to 800.??????

 

you prob have 5 and 6 plug wires mixed up


make sure its wired like this * this is an HO firing order

 

I checked the firing order over and over. It is right.

 

Does the firing order match the cam?

 

a cylinder will fire if it has 4 things.....spark, fuel, compression, and the correct timing

if the firing order is correct its time to check basics, check for spark at those cylinders, pull those plugs and see if they are wet with fuel, if not check your injectors and the connectors to them, make sure they have power and ground using a noid light, if that checks out, time to check compression, check that whole bank and compare the numbers, they should all be very close to the same, if not suspect miss adjusted valve lash, to verify pull that valve cover and visually inspect. good luck

 

lots of things to check here, spark plug wires (make sure there are no burns) spark plug gap. compression test, leak down test, swap injectors and see if it changes. you could have a bad injector. there are so many things that could be the culprit its hard to say with the amount of info you have posted.