This is gonna be a long one so hang in there with me, all of the major repairs that could be related to my issue are as follows
2008 Chevy hhr 2.2

approximately 2015 the car was taken to a 5 minute oil change place, they didn’t put the drain plug back in and the engine locked up, they replaced the engine
in 2020 the car was t boned and parked for 3 years, my dad went to get it running after insurance never paid out, it had no crank no start, he replaced the starter, no crank no start, we jumped the starter and it would crank that way, but not start, had communication errors with the ECU, ordered a pre programmed ECU and provided the vin and whatnot, basically plug and play replacement, they said I needed to do a key relearn so I followed their steps at least 10 times with no results, still no crank no start (all electronics went off in car when I turned key to “crank position” like it would when you start any car, except nothing happened, they came back on when it let it go back to “on”), anyway I sent it back to them and they deleted the VATS, said their test car started up with no key relearn needed now, so when I got it back installed it once again, same issue persisted, well I got tired of dumping money into this car (new tires, battery, rims (one got bent in wreck), other misc expenses, so I hot wired a push button in, use the key to turn the Infiniti on “on” push down the momentary button til it starts up, let go and bam, running car… it ran for approximately a year this way, misc codes I could probably list if I looked in my camera roll, and then one day I was following my wife in the highway and she said everything turned off, engine cut off, all electronics flashed off and back on, she put her hazards on (couldn’t be seen from the outside, the blinkers weren’t blinking), I got it towed home, started messing with it and noticed the gauges don’t come on, but the display does, power locks don’t work, power windows don’t work, rear hatch outdoor handle doesn’t work (it did on the side of the highway, weird.) hooked up a snap-on solid and got no communication to BCM or ECU, called the ECU company, they said send it in we’ll see if it has codes on it, reflash it and send it back, before I shipped it out I cleaned all grounds except the ones under the seats I couldn’t find them and was short on time, and noticed the nuetral safety switch on the transmission was just… unplugged, anyway I plugged that in and kept moving, same issue persisted (except I have reverse lights now I didn’t the entire year prior, chopped that up to the neutral safety switch, small wins, yay!), the ECU company called and said the ECU is fine no codes related to my issue, they recommend I replace the BCM but don’t sell them, so I ordered one off eBay (these things seem to be rare for 2.2), plan to get the vin and mileage programmed, and install it and see if it fixes my problem, now, I’m not an HHR guy and I’m seriously started to dislike them after this thing lol, what do you guys think it is? Do you think it’s the BCM or something else throwing everything off


side note after writing this, not getting fuel pressure so I assume the fuel pump isn’t being kicked on (can’t hear it), fuel pump was replaced less than 3k miles ago, does the BCM control when the fuel pump kicks on? Any tips and tricks I can try would be very helpful, I’m not an electrical guy but I can navigate my way around because I’m poor 😁
thanks, Jackson.

 

I couldn't make it through all of that. Any shop the recommends replacing computers is lazy.
The most common causes of no crank after a collision or a long sit is either varmints chewing on wires or the under hood fuse box needs to have the 4 bolts holding it together tightened. The way to tighten them is to loosen them and then tighten them down like a gorilla.

The fuel pump only runs for 3 seconds if the engine is not running.

 

X2^^^^^ what he said! Especially the 4 bolts in the under hood fuse box. And push all the fuses and relays firmly into place in the BCM even the one on the back side of the panel.

 

95% of BCM that are replaced are perfectly good. You need an automotive technician that specializes in electrical. Load testing circuits will find the problems.

 

You can borrow a fuel pressure gage from Autozone.

How old is the battery?

 

The battery is approximately one year old, it is a 3 year Walmart battery. I will try the fuse box trick and I have already checked all grounds and checked for critters tearing up wires.

 

The age of the battery does not matter. The voltage does. It should be above 12.5 volts engine off. The alternator should be putting out about 12. 7-13.5 engine on.

 

Sure it does. The older battery, the more likely it is to be the problem. I asked to gauge how best to broach the subject. Advice to check a one-year-old battery will be likely be ignored, even if it sat outside dead all Winter. Not that it will always help to ask, because often, advice about checking into the battery condition is ignored. How many times has someone insisted the battery is good when it’s eight years old, because it starts the car just fine?

But you’re right; what really matters is whether the battery functioning as it like it’s supposed to, i.e. is it providing something like 12.6V or better with sufficient power?

Parts store battery test are useful for the data but not the advice.

 

CCA readings are important for determining battery energy. A battery load test is required, no matter how old a battery is, we’ve seen many report dead brand new batteries. Fresh off the shelf.

 

The shop didn't add any oil? I would think that the oil pressure light would have turned on before the car was in gear to back out of the bay, soon followed by knocking.