First off I want to apologize to this forum because the last time I posted I felt like I wasn't being attacked by some of the replies. Some were really trying to help me and I was just so upset that I couldn't get past it. Something I learned though about this car is that anytime there are engine issues it will turn off features such as traction control and ESC to help not put so much pressure on the engine. When I was having those issues back in 2016 it turned out to be crank shaft sensor and cam shaft sensor codes. We replaced the sensors and the issue didn't go away. I eventually blew the engine.

So the engine was replaced in August 2020 with 2.2 ecotech from an 09 Cobalt LS. So I don't know if I should get help here or go to a Cobalt forum, but you really did try to help me so I figure I'll start here.

Car ran fine after the engine was replaced. I blew the first engine at 126,000 miles. It had the timing chain issue. Anyway it ran fine but I was getting a P0446 code and was having issues putting gas into it. That comes back to either the purge or vent valves. I have not replaced those yet.

Right before Thanksgiving 2020 it had a small leak somewhere in the exhaust because I could hear it. While driving it the pipe broke open right before the flange where it connects to the exhaust manifold. It didn't fall off, just opened the hole larger. I had to replace that entire pipe with the cat and resonator as all one piece. When that broke open it threw the P0301 code and a P1174 code and the P0446 code went away.

So far I have replaced the cat, the spark plugs, the mass air flow sensor, and the fuel injectors. I only have code P0301 now and you can feel the misfire while driving it. We checked the fuel pressure last night and it was around 60 psi while running but 0 psi with key on engine off.

I am at a loss as to what else to do. All suggestions are very much appreciated.

Thanks,
Jessica

 

Jessica, we’ll help you with this.
First off you say you haven’t replaced the EVAP canister under the car, or the EVAP purge valve up under the hood, correct?
Second you now just have the P0301and that could be as noted here that
code P0301 may mean that one or more of the following has happened: Faulty spark plug or wire Faulty coil (pack) Faulty oxygen sensor(s) Faulty fuel injector Burned exhaust valve Faulty catalytic converter(s) Running out of fuel Poor compression Defective computer

Read more at: https://www.obd-codes.com/p0301

Copyright OBD-Codes.com

now you replaced the catalytic converter, so that’s eliminated
you replaced the fuel injectors, their eliminated

did you replace the O2 sensors, you shoulder a different code for those.

you said fuel pressure is at 60 psi but goes right down to 0 when you turn the key off?

based on this information, I believe you have a weak fuel pressure valve, that would require replacing the fuel pump.
it’s not a hard job but it can be tedious especially if you do not have a lift. I’ve replaced the fuel pump in my ‘07 2.2 LS in my driveway just hand tools and floor jack and jack stands. Drive your car till the low fuel notice dings, that should leave just 2 gallons in the tank , if the darned border was opened up, I’d come over and coach you how to perform this R&R

just to confirm, what spark plugs did you install? AC Delco 41-103 Iridium, I hope

 

Correct, I have bought the vent and purge valves but have not yet installed them. I did replace the O2 sensors when the cat was replaced. The spark plugs are double iridium, pre-gapped, but they were Bosch brand. I actually had to go back and double check because I spec'd them for my HHR not the Cobalt engine but they were the same plugs for both, thankfully.

I have access to a lift or a hole in the floor. LOL I know that sounds weird but I had a Cavalier over 10 years ago that the fuel pump went on and my mom and step dad cut a hole in their garage floor to fix it. They have since built a garage out back and installed a lift. But I don't do the work myself. My cousin does most of it. I did take it to a shop to have the engine installed though. And I don't want to ruin the engine because it only had 21,000 miles on it when I bought it. I've put a little over 3500 miles on it since it was installed.

Would that valve throw the P0301 code? My only consolation is that the pump is $50 cheaper at Autozone that Rock Auto. LOL Weird!!! LOL

Thanks,
Jessica

 

Now hold the phone, those Bosch plugs have been known to cause issues, in my ‘07 I them and experienced a misfire , possibly try the correct spark plugs first, do not attempt to gap them they come gapped correctly. Either order a set of four from RockAuto or pick them up at your local parts palace, but specifically the part number I posted earlier.
What brand fuel pump are we dealing with at either source.

 

As suggested, you should replace those Bosch brand plugs with the correct AC Delco 41-103 Iridium ones.
When you pull out the old plugs, you should do a compression test on each cylinder.

 

I think you should pay a real mechanic, they might not throw as many irrelevant parts at the problem, at least they shouldn't. NOT an attack, just advice; you have listed $1500-3000 worth of unneeded parts thrown at problems. For instance: "crank shaft sensor and cam shaft sensor codes" does not mean the sensors are bad, it means the timing chain getting close to breaking, thus a blown engine. You don't have to replace the entire cat just the flex joint. You did not mention any reason to replace the MAF. If the codes have gone away there is no reason to continue replacing EVAP parts, it was probably your gas cap loose. You have not cited any reason to replace the injectors.

Step #1 is a compression and leak down test. That will tell you the health of the cylinders and valves.

Is coolant disappearing? Is the oil level growing? Have you ever checked the coolant level under the pressure cap?

Use the correct spark plugs, NOT what the guy at the store is getting a bonus for. ACdelco 41-103.

Why do you expect the fuel pump to pressurize when it is turned off? The test should be about 50-60 psi running then not lose more than 5 psi in one minute after shut down.

Nobody is attacking you! We are trying to help but some questions need answers. Not all questions are accusations.

 

I will get the correct spark plugs this weekend and swap them out. They've been replaced twice since December. I was driving with the mass air flow sensor unplugged because it shifts easier and it causes the plugs to get swamped. Auto zone replaced them under warranty. But I'll get the AC Delcos like you suggest. I don't know how to do a compression test on the cylinders or if I even have the correct tool to do it. I'll try whatever I can though.

The fuel pump is a Delphi Gasoline Fuel pump DFG1219. It's the same one at Rock Auto also. - https://www.autozone.com/external-en...219/555943_0_0

The purge valve is PV443 and the vent valve is PV483. Figured I might as well make sure I got those correct before installing them.

Thanks,
Jessica

 

I picked the spark plugs. I though Bosch was a better brand.

I've had it at the shop. They said they swapped injector 1 with injector 2 and the code switched. Problem is I didn't test it myself before actually changing the injectors so don't really know if that code had switched. Either way changing the injectors didn't solve it.

I want to try whatever I can before taking it to a new shop. At least I am saving a little on labor by just buying parts. My cousin doesn't charge me to do the work but he is thinking it's the fuel pump also. He wanted me to ask on a forum to see what others could suggest. I came back here.

Thanks,
Jessica

 

This is a compression gauge

hold off on the fuel pump, remove the spark plugs

remove the fuel pump fuse in the under hood fuse box #13 , I believe

your cousin should know how to do a compression test.

all 4 cylinders should be within 15 % of each other, 150 to 180 psi.

write the numbers down and post them here.

get the AC Delco plugs and install them after the test.

 

https://www.chevyhhr.net/forums/how-...-engine-56053/


Please re read #6 I was editing while you were typing.