Newbie engine questions.

[ssgoodman]

let me start off by saying i am a complete newbie to TBI and really dont know much about engines in general.  i got some good tips from Vile on another post but i cant really put them into action since i am an idiot.  first question is where are the vacuum lines on a 90 350 TBI engine?  would removing the cat and installing headers screw with the computer?  how do i go about "programming and reading codes" on the computer for the TBI, is it something i can do on my laptop or do i need to buy a specific computer?  what spark plugs should i get to replace the seemingly factory plugs in it now and what is spark plug gap and how do i do it if i need it?  and what is that little flexible tube that runs from the air cleaner assembly to the manifiold on the passengers side and do i need it? 

the jimmy i bought runs like crap, it idles rough, it likes to die when i am in reverse and it gets bad gas mileage.  tomorrow i am going to try to do a tune up on it the best i can and do alittle digging around on it, seems like getting in there and getting my hands dirty is what i really need to understand this thing.

edit: another thing i forgot to add, does anyone know what would be hitting the driveshaft tunnel when i take off from a stop?  it only happens if i give it the onion, if i easy into it there is no clunking.
thanks
Sutton

[Blazin]

Sounds like a broken transmission mount as far as hitting the floor.
First thing you should get a Haynes, Chiltons, or Helms manual for your truck. Helms is the best.
 If you are going to install headers get the ones with an 02 sensor bung or weld one into the ones you get. I would install dual aftermarket cats.
 as far as reading codes in can be done with an inexpensive code scanner. Alllot of parts stores, or tool supply places carry them.

[VileZambonie]

You can download software for your laptop and but the 12 pin ALDL cable to not only read DTC's but to read datastream. Winaldl, obd, etc...just google it http://www.aldlcable.com/

Which specific vacuum hoses are you trying to locate? The VECI label under the hood should have an emissions routing diagram.

I agree with Blazin, duals with Cats if your state requires them. It will not throw off your computer as long as you have the O2 sensor in one of the headers.

For your spark plugs use AC Delco R43TS. The gap is .035" that's thirty five thousandths of an inch. It's the distance from the ground electrode to the center electrode. You can use a plug gapper or feeler gauge to verify the gap. All should be parallel and equal distance before installation. Always start the spark plugs in by hand not with a socket. You can use an old spark plug wire boot to thread them in nice and easy to avoid cross threading.

The flexible hose coming off of the exhaust manifold to the air cleaner if for early fuel evaporation (EFE) it's called a stove pipe. The stove pipe works with a thermostatic aircleaner so when the engine is cold it draws air off of the hot exhaust manifold to prevent the fuel from condensing back into a liquid during start up and cold climates. once the thermostatic air cleaner stops receiving vacuum through a TVSV (Thermostatic vacuum switching valve) it draws air from tha aircleaner snorkel instead of off of the manifold. If you are putting on headers ditch the stove pip and thermostatic air cleaner.

I agree with Blazin again, check your mounts and your u-joints. Check your leaf springs and bushings also.

As far as it stalling you need to do your basics, tune up, set the timing, check all the stuff I already recommended in the other post. If you have the ability to read your datastream that will really help so you aren't just throwing parts at it.
 

[Captkaos]

I can tellyou how to make a cable that will work with the ALDL connector and WinALDL, you just need a laptop (any will do) with a 9 pin connector.

This is what I use with WinALDL..