So I dont know if any of you know alot aboutt LS motors but here it goes.

Car is a 1991 hatch, engine is from a 93 teggy, obd1, intake and exhaust. I rebuilt the engine about a month ago and it has been running fine until a couple days ago. It stated lacking a little power and feeling a little like it was missing. So I got new plug wires and some sea foam. Plug wires made it seem to idle a little smoother, the i sea foamed it and after seeing the biggest smoke show from that amount of sea foam ever it idled perfect. I put about a quarter of the can directly into the brake booster line, half of what was left in the oil and the rest in the fuel tank. It seemed to run OK though still a little hesitant. Then I went for a drive after work 45 miles there 45 back. About 30 miles in i tried flooring it and it literally felt like i hit the breaks, I try again and no luck, so I just cruise it the rest of the way. I let it sit for 1.5 hours then took off. All seemed ok again until i got on the freeway, I stomped the gas and it was really not moving like it should, so i downshift to 4th and still nothing. it took a little hill but I finally got back up to 80. Then I hit a small hill and had to floor it to try and keep that pace, and when I floored it the whole car shuddered and I got down to 55 mph. When I started down the other side it wouldnt go over 60 mph without shuddering, I couldnt rev over 3500 in any gear or in neutral and I still had 15 miles to go.

My guesses are dying distributor or the amount of carbon knocked loose from the seafoam coated my o2 sensor and the ecu isnt getting a good reading causing the problems.

amy help would be greatly appreciated!!

could be a bad tps sensor as well that isnt reading right

Wouldn't that throw a code constantly??

A little more info for you guys. A couple times a day it will throw code 43. Today I checked out my spark plugs and o2. Both of which are extremely white which means the gas is burning perfectly right? I'm pretty new to this scene so bear with me while I learn.

Code 43 is a fuel related code. Most likely due to a bad O2 sensor. Change the sensor and go from there. If you touched the sensor or got any fluid on it that will cause it to die. Make sure you dont have any other codes. Change your oil and get the seafoam out of there. It is a type of solvent, no matter what the bottle says it will break down your oil. This will cause the oil not to lubricate properly.It does clean the pistons and valve nicely though. I always use Valvoline top engine cleaner, it comes in a 3 part with fuel injector cleaner and throttle body cleaner.

Well I never touched the actual o2 sensor. Just the top part. I did clean it wiht brakleen last tine I got code 43 and it went away until yesterday. I will get the oil out of there asap abd that was my plan anyways.

So changed my plugs cuz I figured they were fouled and it ran a little better but my air fuel gauge says I'm still running super lean so the next thing I will try is the o2.

it could also be a bad fuel filter

i bought one and will install it later. Another thing I have noticed is it sounds like my cat has crumbled

he is what u do since u have a 93 ls disconect the 02 censor on the header/manifold whatever u have and run the car if it runs fine that means u have a bad or clged cat and need to get a test pipe lol no u need to replace it i had a similar problem car had no power it was my cat if nothing else works check the timming and if u have white plugs i would advance the dizzy

I might as well not replace it and just run the test pipe since I have the innovativ mounts its just going to happen again

yah dont know the law where u live if u can pass inspection do the test pipe if will also free up some power

Decided to go with this guys advice and all I have to say is THANK YOU. Sounds like a fart but all is better. Waaaaaaaaaaaaaaaay more torquey too

your welcome