HELLO EVERYONE!
Ok so here's the deal. Washed the engine after swapping out failed alternator. Left engine running for 15 minutes after wash and all seemed fine. Next day, engine would not run. Engine starts but turns right back off. Tried pressing gas pedal to see if it'd rev but nothing. Fuel pressure is good. Enough fuel in tank. Removed and reinstalled gas cap. Oil is also good. Battery connections and voltage are good. All connections are in place. Unplugged all connections and blew with air hose. Removed coil packs and spark plugs which led me to see that some moisture had gotten in, mostly in cylinder #1(milky looking oil). Cleaned all packs, plugs and insides. No codes using the OBD2 since battery had been taken off. All fuses are good. Previous code was malfunctioning evap system among others. Bought car used a couple months back and it was running like crap. Changed 2 coil packs, problem solved. Car is lit up like an x-mas tree just like other posts ive read (engine service, tran service, brake asap, etc). Before alternator went bad, also had the issue of car going into "limp mode", not responding to gas after a while of driving or just completely shutting off. Thought it was the fuel filter which i replaced but no. If it shut off, putting it in neutral and restarting would almost always work. When going into limp mode or not responding to gas, i would shut the car off and switch the two relays in the engine compartment fuse box closest to the driver which 8/10 times would allow me to keep driving.

Could this issue have gotten worse after the engine wash? Where is the evap canister located? I know these cars are notorious for electrical problems and replacing the ECM in most cases might help with all the other issues but it always started up until now. Im stuck on what else to check. Cant be MAF. Sensor on cyl #1? Throttle Body? Any help would be appreciated. Thanks in advance.

 

Sounds like you got water into something you shouldn't have. Unfortunately with an electrical issue it's going to take time to figure out where.

 

:/ What ticks me off is that it was running fine after the wash...and i've washed the engine bay before with no problems.

 

It may have, but water is a tricky thing, it can slowly seep into connections that it is not suppose to, which could be your case. Or it could be a complete coincidence.

 

How about checking the throttle body, don't know what year you car is but this problem sounds just like the problem we have had 4 times different with the throttle body, which by the way has a recall and Volvo extended the warranty to 200K.