I need help family. i have a 09 hhr ss and on Father's day it started to run funny misfiring. I thought it could be a fuel pump(idk why?) but I swapped that thinking it could be. i was clearly wrong but i hooked up my obd2 bosch scanner to it and it read error cannot communicate? cel is flickering rapidly and ignition is allowing key to turn freely just no spark and engine wont turn over ?
did i fry my ecu? IO need help to fix my daily as its my only vehicle.

 

You changed the intank electric fuel pump or the HPFP under the hood?
Check fuse box , red wire in front left of it is the power wire from battery to fuse panel then to starter.
check maxi fuse in spare tire well near the battery.

 

I changed the fuel pump thinking that was it I didn’t know about under the hood I’ll check that but shouldn’t I at least get crank on starter

 

Plus I have no connection on the obd2 it says cannot link ? Is my ECU dead?

 

The fuse that goes to the cigarette lighter/power outlet also powers the OBD connection. Check that fuse (#29 I think) in the engine compartment fuse box.

FYI. Your SS has 2 fuel pumps. The supply pump in the tank and the High Pressure mechanical pump (HPFP) that is on the engine.

 

Yet does that account for not being able to read the ECU? That is the scary part! Well not Only that of course it won’t start.

 

Has the ignition recall been done? Link to check recall status
What did you do that might have fried the ECM? Did you cause an arc with jumper cables?
"Failure to communicate" may mean the cig lighter fuse is blown. Fuse #29 underhood fuse box. Or a bad Paul Newman joke about hard boiled eggs.
Could be one of the relays or fuses.

 

Apparently you don't understand car electronics. You say ECU but that is just one of many computers or modules that are on the car. And it's technically an ECM.
Like I stated, you can not connect a scanner or code reader if the OBD port doesn't have power to it. Check fuse #29.

 

However, a flashing CEL means "PARK ME NOW, TOW ME TO A MECHANIC".

 

Yes I’m a noob. I mechanic by any means just I try before I buy new to fix it checking now!