Need Help Car Is Acting Up

[birdman LS1]

HEY whats up i need some help i was just driving along and my formula with a 5.7 was going then like almost bogging out then suddenly kicked it after a large throttle lagg response time was horrible i need some help i thoght it was my gas like maybe i was running out but my check engine light turned on what can it be???

[tuske427]

What year car? You mentioned the "check engine light" came one. This means a trouble code was created and stored into your car's computer. If it's 1996 or newer it has an "OBD II" (on board diagnostics generation 2) computer system. This means that you can go to any local "Auto Zone" and rent an OBD II scanner tool and plug it into your car. From that it will tell you exactly what the trouble code is in plain english. It's really easy. And this rental tool allows you to erase the trouble code(s) too. If it's older than 1996 (obd 1 or even before that) there is still a "trouble code" if your check engine light came on, but it's not as easy to decipher.

There are websites online that tell you how to do it. Something about the light flashing like a morse code and then you need a conversion list to decipher that. Not so convienent. Check some f-body enthusiast websites. I've seen them listed before, but don't remember exactly where.

[FormulaForce]

My 95 Formula is doing that due to a dying fuel pump. It comes and goes. I'm waiting til I get my new driveshaft to fix it because it's very difficult to get to. I have also had that problem with a bad ignition module and again with the LT-1's optispark distributor, also a nightmare. Your login name indicates an LS-1 so it must be a 98 or newer. Like Tuske said, a scanner for OBD-II codes should tell you. Good Luck

[birdman LS1]

alright so here is the thing i have a 94 but it is a swap with a ls1 the deal is i have obd 1 so i gotta do the mose code bull shit . i jsut got a new fuel pump and put one in today and it was running good for a lil then whent back to the same problem just not as bad it would only do it once in a while now but still what can it be ?? when i plug that lil pin in to the computer it doenst even make it flash ..? i got some fuel injector cleaner should that help ? what do i do guys

[tuske427]

If I understand correctly- the car is a 1994 and you have installed an LS1 in it. What wiring system is running the engine? stock/ modified GM harness? painless? something else?

This complicates things.

how often/ soon does the engine cut out? do you have to drive it a while, is it random or does it seem almost regular?

I ask this because it could be something as simple as a lose wire grounding out somewhere and shorting your ignition or fuel supply. This type of thing happened to my friends camaro once. He wired in a tach- and when he'd shut the door the car would stall. open the door and it's start. I was able to notice the pattern and figure it out. turns out the tach wire was exposed and grounding out on the car.

when you have engine swaps with wiring systems, you have the possiblity of electrical gremlins if it wasn't done properly. did you swap this yourself, or have it done? did you buy the car like this?

the more info available, the better it is to help.

Let us know.

[birdman LS1]

ok well i figured out what i changes was a fuel filter aNd not a pump so that did nothing ... for the first 10 min when car is cold it drives good ..... then it almost seems regular to hesitate between 2k-3k rpms .... plz help someone

[birdman LS1]

HEY also i bought the caR with the swap done it was done professionally ..also some one told me it might be a O2 sensor or the coil ?? ur thoughts

[chiefsmackahoe]

"ok well i figured out what i changes was a fuel filter aNd not a pump so that did nothing"

step away from your car and take it to a professional!

[Mr. Luos]

An LS1 won't run properly without its corresponding years computer. I am sure that was done if the swap was done professionally.
Now, does this change the prong to the PCM?? I don't know.