So, I got my car aligned, got it all buttoned up and ready to drive and have been for about a week now. I absolutely love it because it handles like a dream now! Car was down for about 2 or 3 months only being once every couple weeks or so when it was actually driveable.
Anyway, I am starting to come to the realization (spoiler alert) that this car still needs a good bit of WORK. Now for the issue I have...
Here is the scenario, I am at a light, or in stop and go, and as I take off in first gear, I get this stumble and it almost feels like a shift. And this stumble usually happens right before or after a shift, maybe a second or so it seems. The engine 'stalls' for just a quick second then it goes right back to running fine. Like I said it feels like a shift, its soft and smooth oddly. The other thing I notice now too is that the thing stumbles very hard when I am stopped. Scenario, sitting at a stop light, foot lightly on brake and the thing will just pull through the brakes for a quick second and you can feel the engine rock the car a little, and then the car stops and goes back to running 'okay'. Its very odd and COMPLETELY random. I also get an extremely noticeable amount of chugging and pulsing using small throttle inputs around 0 MPH, the same also holds true when I try to stop if I am under 10 MPH. Now I know I am of no help considering I have no datalogging capabilities (yet), but to me this has to point to a couple things:
EGR/solenoid sticking from build up causing the stumble. Seems reasonable as the car spends most of its time under 2K rpm, I try to blow it out every so often..) Want to replace when I do intake manifold, f-body of course.
Bad ICM. Replaced coil over the summer.
Opti? Frikin long shot here, but the thought has run through my head. I know it has a wobbly bearing, but a new cap and rotor. like that helped...
Something else I havent thought of..
I checked fuel pressure a few months back, but I really need to check it again, and it was fine. I dont suspect a sticking lifter, I use a friction modifier(whatever that means...)
ALSO, and this might be the kicker, I notice my EVAP doesnt work, crack gas cap and the thing has a TON of pressure Trying to fit in replacing the vacuum line for that here soon. I wonder if my line has collapsed, or worse, separated, and now just sucks straight air and when the solenoid opens it gets a huge gulp of air. Im not sure exactly how the EVAP works, just enough to be dangerous, but as far as I know that could also be entirely wrong.
I have always had a roughish idle once warm. Not as smooth as a grandma car LT1 should be, but it always ran incredibly well once the TB was opened.
Thinking I should just do the EGR because its pretty easy and could probably use it.
Hopefully thats put together in a decent way...