How do i check my engine codes for a 1994 sc auto.also help me figure some things out

FrankenBird

Registered User
OK, heres whats up. my car just had the heads rebuilt to stock spec, new HG's every other on up gasket plugs wires belts and new fluids.
its mods are slightly ported MP sc and slightly ported MP plenum , 7% sc pulley , 75mm throttle body , 3in intake , stock mafs ( do have a c&l 73mm with red tube i believe) 42lb fuel injectors , knock off griffin radiator . i also have my ac condenser removed for direct air to the rad and intercooler.
heres my issue, the car actually runs great and holds a perfect idle.. BUT it seems slower than it was when it was stock, could it be it needs a tune that bad?
if my car just sits at an idle the cel wont go on. it takes a few min of driving befor it comes on.
Can someone please tell me how to check the codes, im not two smazrt so more info the better !
I am trying not to drive the car but sometimes have to if i gotta get the kids some where. since the rebuild and all the mods added ive put on a bit over 200 miles. i also have 8 16oz bottles of octane booster. should i dump them all in and run premo just to be safe not to run too lean? according to my shortband afr gauge it runs stoich at cruising speeds but is rich at a stop and when wot it is full out rich. in park it is barely hitting the 1st green line for rich but is mainly stoich..
my car is also only hitting 13lb of boost and in gear at a stop like 17 vacuum i think maby abit more. when i go wot from a stop it cant even chirp the tires.
i test drove one a few years back all stock and ratty looking engine but id take off the line and leave like a 10-15ft buron out.
I wanna run the codes just to make shur its not something as simple as a tps not taking it to full throttle or something or maby a dirty mafs.It also felt like it stuggled to get above 90mph but i didnt wnna push it any more being not tuned... I just have no clue. HOW CAN IT BE NOW SLOWER THAN MY WIFES 99' 4.0 JEEP LAREDO.
should i get a 10% pulley? is my car not making enough boost for the such a larger intake system it now has? i hear that sc loud and proud seems to get in and out of the gears like it should.
i wanna start by running codes.
i now bring my sacrifice to you sc gods and upon it i wish for you to bestow on me the ability to read codes ! ahhhhhhhhhhhhhhhhhhhhhh meeeeeeeeeeeeeeeen
 
Are you running the 42's with the stock maf and are you still running the stock fuel pump?

I know on the early SC's you can you a paper clip to read codes by counting the flashes of the cel. On the early SC's the test port is in the engine bay on the passenger side of the firewall. Not sure if it's the same location on the late models.
 
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I would buy the obd 1 code reader just to see what is throwing the cel, it is probably pulling timing to keep things from melting down which equals less power. And yes it probably needs a tune that badly. I believe #42 injectors need a yellow sample tube.
 
I would buy the obd 1 code reader just to see what is throwing the cel, it is probably pulling timing to keep things from melting down which equals less power. And yes it probably needs a tune that badly. I believe #42 injectors need a yellow sample tube.

i saw on some chart it said i swear i think red. but that was for 89-93, i couldnt find anything listed for a 94-95.....ille look into the yellow tube because yes i am using the stock mafs. the c&l 73mm at wot around 40 it has detination so ive left the stock mafs..and yes i have the stock fuel pump. it runs rich according to my afr gauge most of the time so i doubt i have a lean problem.The car just feel like it should have more power than it does..
with an obd1 reader wheres the port on a 1994 sc ?
 
You need a wideband to really know what's going on. Who knows what that is seeing as your running 42's without the correct sample tube and a computer programmed to run 36's.
 
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You can use the C&L with the correct sample tube for 42's but it still wouldn't be perfect. Really you should have a tune regardless of which maf you use.
 
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