tl;dr changed egr
vacuum hose and put seafoam in tank, now car idles very rough and stalls out.
Alright so I am at a loss right now. Im just going to give the full story in hopes that someone thinks of something obvious.
Recently I noticed that my engine has been pinging (Its been in the triple digits recently and my commute has a lot of uphill driving. hills + ac
= high load.) Since the car is about 20 years old I figured it wouldn't hurt to run some seafoam through the gas tank to help clean it out. So i dumped a full can into the fuel tank while it had about 6 gallons in it last night. Then in the morning, drove it 5 minutes to the gas station to fill it up and went to work. When I got in the car to go home and started it up, it pretty much immediately threw a P0171 and P0174, which didn't really surprise me since the car has had a rough idle since I bought it, and because I noticed the other day that one of the egr
pressure feedback hoses had a hole in it.
When I got home, I figured I would scan it to see if I could figure out why the code was set, and sure enough my fuel trims were all in the 20%s (so about 40% Short Term + Long Term on both banks) Poked around for awhile and didn't really see anything other than that broken egr
hose and decided to replace it.
Went to THE ZONE and got a new hose, replaced the old one and.....
As soon as I started the car it was making a loud hiss and stumbling all over the place, checked the codes and a P0300 had popped up. At this point I took off the new hose and replaced it with the old one but the issue is still there. Then I tried random things like unplugging the IAC
and checking the rest of the hoses but nothing seems to change the misfire and stumbling.
Its pouring rain right now so I can't go and check the rest of the stuff I want, like the fuel pressure or the spark plugs, but I am extremely confused as to what happened here. I doubt the seafoam or the vacuum hose have anything to do with this but geez if itsn't a massive coincidence. Almsot forgot, I also added about 5 oz of seafoam to the crankcase as well, but again I doubt that has anything to do with it.
So .... thoughts?