M1ke

when you take a car to a service shop what exactly is done for a tune up? my car's running kinda rough and the engine sounds bad to me and im thinkin about taking it to a shop. Ive replaced the spark plugs gapped about .049, plug wires w/frpp 9mm wires, air filter, and i cleaned the iac. idk what to do and id like it to run like new like my dad's 03 that runs so smooth. i have a 96. also does anyone know what the black **** on a 96gt's iac does?

Chopper

As a car ages things like cam timing and individual cylinder compression deteriorate and cause rough idle.To get back the new car smooth idle you would have to do things like replace timing chains and guides,rebore cylinders and put in oversize pistons.Bearings wear and cause loose tolerances throughout the engine and all this adds up.There is probably no one thing wrong but a combination of small things.

M1ke

how much would all that cost?

Chopper

That depends on the shop.Labor will be a major cost unless you can remove and replace your own engine.To keep your car on the road you might consider buying a used block from a junkyard,sorry,recycler,and reducing it to it's individual parts and having the machine work done as money becomes available.You can add better heads,forged crank and pistons,and cams at your leisure.When you get your new creation finished just swap engines.Instead of being down for weeks,you should be able to change the engine in a weekend.This approach is how I'm going to do it if I can get my Chief Financial Officer,Mrs Chopper,to OK the funds.Probability,slim to none.She says"if it ain't broke,don't fix it.Now it's up to me to break something.

M1ke

thats what i was afraid of. i had just wanted to do a p&p on the heads ad a cam and a aftermarket intake man then some boltons to get around 300whp but my block does have 100k miles on it. bad thing is that i dont turn 18 till beginnning of feb and thats when ill be job searching so all i have money wise is tax returns that i dont even have yet so it'll take a loooong time for me to get the whole shebang completed and swapped. But on the other hand, this'll be a great learning experience if I get some good books on engine building and learn some stuff myself.

mustangemt

Ok first thing is the black **** on the IAC is a breather cap. Also many things may cause a rough idle. Some brands of plugs don't work well in the ford engine, stick with motorcraft. Also i see you have modified the exhaust. Did you improve the intake air with any mods??? Some MAF sensors can be affected by the airflow changes and may cuase some drivability concerns. As you increase performance many times you sacrifice some idle quality and drivability. In extreme cases a special program may need to be programmed into the PCM to reset the parameters for the best performance and or drivability.

M1ke

there wasnt any difference in how the engine ran when i changed the spark plugs. its really been the same for a while. the exhaust is the only thing ive changed and i checked the maf and its really clean.

im gonna call some shops tomorrow to see what they do but ill check into engine building