The car won't stay steady at any miles per hour. When I keep my foot steady on the gas, it will slow down and then kick back in again.

like this, i'm keeping it at 30 miles an hour, it will slow down to 20 or 25 and the car will jerk back into 30mph. I already changed the idle air control valve, which was assumed to be the problem but it wasnt.

I have a ls block with a b16 head
with a chipped gsr ecu. not sure what chip it is
manual transmission

If anyone can help it would be great.
I need this car to start working, my job starts in a week
LET ME KNOW ASAP THANKS!

 

Oh and it use to be supercharged before

Maybe a good tune?

Anyone know?

 

bump

 

check the connections on the tps and the map sensor and also test the sensors...

 

all sensors are good
no check engine light

 

does it run bad too like its dying out or does it just slow down. i would say check the lines. possibly a vaccum leak?

 

not dieing
just slowing down and jerking

Checking for vaccum leak in the morning

 

no leaks

up up! need some help ppl!

 

Is the chip in the ecu the same one they used when it was supercharged? It could be your fuel and timing maps way out of whack.

 

I had that same problem when I had an EG... it turned out to be the ecu was automatic when the car was manual just letting you know cuz it was the same symptoms, try using another ecu... good luck