What's up all.

When driving at highway speeds up to 70 mph when I go to let off the gas to decrease speed drastically, or quickly causing a sudden drop in MPH, my car will jerk back and forth and hesitate. The engine skips briefly for periods and will continue to do so until I get to any MPH on the road, this usually will happen when driving up onto somebody on the highway and having to slow down some. My car is 5-spd manual transmission as well. Recently replaced PCV. plug wires, I have recently replaced my TPS and had my MAF cleaned well as well. Also, a lot of black soot is accumulating at the end of my muffler tip, and its black as ever. Is this a problem? I had new exhaust put on recently. I put a whole can of sea foam in the gas tank to try and fix and had incredible results, after running out the half tank I used it with, the problems came back at next fill up. Thanks.

 

When you are engine braking with our cars it should shut down or all but shut down the fuel to the motor until you hit the clutch and idle or hit the gas again. My random guess, randomly leaking injector. Do you ever have issues starting it?

 

No issues starting it.

 

How do the rubber parts of the lower engine mounts look?

 

+1 to engine mounts



Maybe a bad TPS and/or MAP sensor

 

the car obviously has fuel injection problems could not be the motor mounts

I would say it the MAP..maybe acceleration sensor

 

I added a full bottom of sea foam to the gas tank with a half-full gas tank and everything seemed to fixed.

but once again at the next fill up the car started acting abnormal again.

 

Replaced the fuel reg