Figured I should start a new post but a continuation from this one about P0420 bad cat >>>https://www.chevyhhr.net/forums/prob...roblems-65964/

I finally was able to change the cat and O2 sensors. The new cat had a bad smell-sulfur like? - i think it's actually gone now/burned off, but since the car is back to no start, not sure.

So once the car finally started again with the new cat/O2 sensors - such a satisfying feeling of accomplishment for a novice. I also had added seafoam to fuel tank the day before.
I got the following errors:
Mode $6 on scanner gave a 'failed' on heated exhaust gas sensor bank 1....
ODB II = P0134 and P0135 and P0300 pending

I checked my connections on the O2 sensors -they were hooked up correctly. Decided to try hooking up the old upline O2 sensor that i hadn't removed yet - that caused the car to not run at all so I reconnected the new O2 upline. Car started back up again so I took it for a few short drives and it ran fine other than at idle which it ran a bit rough/low 500-700 jumpy range so i kept the rpm up to 1000+ and it went away.
Next day I drove about 25 miles with the rough idle issue at lights, but acceleration and running at speed was fine. Before heading home I did the upper seafoam treatment with the red hose inserted into the intake where you run the car at 2000rpm while emptying the can - about 8-10 min.

Let it sit for about 30-60 min. PCV hose had sheared off an inch from the engine intake so I pushed the remaining hose onto it - seems like it's narrower than the end bit - and started to split a little, but figured the clamp would hold it in place till i could get another.

Started up - not much smoke. Ran good again and rough idle gone and P0300 code gone and Mode $6 codes all come up PASSED.... but still showing 0134 and 0135 codes. Drove about 15 min and stopped at a store for about an hour - car started up brielfy and ran terrible before dying - checked under hood and found the PCV hose had completely broken off - - - tried to macguyver it but couldn't get it to start. Ended up towing it home.

Today I intalled a new PCV hose, pulled spark plugs to see if anything was fouled - all good - able to shine light down into cylinders - looks a bit black? - put it all back together and car won't start. A few times it would turn over briefly but never catch.

Think i need to pull the [new] battery and go get it charged up - odb showing it is now down to 11.6V whereas before it would show as high as 14.7V on the scanner app - not sure how accurate that is, but maybe too many start attempts=weak battery is now my problem - or did I not drive long enough after doing the upper seafoam treatment?
Also don't know why I have P0134 and P0135 codes not going away.

pic of inside cylinder (boosted exposure so you could kinda see the inside better)

 

Get the battery up to snuff and report back. Did you use OEM O2 sensors?

 

got an NTK 21546 for the upstream and a walker 25024354 for the downstream - going to go get battery recharged tomorrow and see what happens.

 

You should check the condition of the Serpentine Belt, it might not even be there anymore. A new battery should not discharge like that.

 

i actually changed the belt tensioner and belt a few months ago - car sat for about 2 months and i think at least a month before i decided i should disconnect the battery until i could work on the car. when the car crapped out the other day, i probably cranked it 30-40 times - didn't keep count.

 

I don't see why P0134/P0135 would keep it from starting. You had an unresolved P0171 that possibly progressed to a condition so lean that it wouldn't fire.

If the P0171 got cleared, it won't reset without the engine running, so the underlying cause it still there.

Your comments in the prior thread(s) indicate that your gut is telling you that fuel delivery could be an issue, and you even asked about the fuel rail and injectors.

I comment more than once about the injectors in that engine are exceptionally fine and notorious for clogging. You never responded. Did you look into it?

I watched the video of the crank/no start. No sign of any ignition at all. One explanation would be insufficient fuel to ignite.

Having re-read the now fragmented thread, I also couldn't find where you ever established proper fuel pressure at the rail, but maybe I missed it.

The P0171 lean condition could be explained by clogged injectors or fuel rail or a fuel pressure problem. Worsening of any of those problems would explain graduating from P0171 to no start.

 

pulp - fuel pressure was checked and determined to be fine. I did pull the fuel rail and cleaned injectors - didn't remember to mention that in my first post here. If after getting the battery charged up and still have a no start, i will revisit the fuel injectors/rail and also the fuel pressure to reverify no new issues.

 

Are the P0134 & P0135 pending, current or historic? Is the CEL on? Did you tighten the fuse box bolts? Did you check the O2 fuse (#33 under hood)? Did you unplug the ECM and inspect the pins?
A fully discharged battery is about 12.3V.

 

codes current. Cel on. I had tightened fuse box bolts. Fuse 33 ok. Never touched ECM. Not sure how to inspect/detach cable connector



pulled fuel rail and injectors again to run cleaning thru same as seen a few people do on youtube. Two gaskets are shot. Think need a rebuild kit like this?
mine are yellow but this kit they are black casings with gaskets? I thought i could maybe just replace the gasket itself but the sizes listed on RA seem to be for the other smaller injector gaskets

 

Also here s video of injectors. First three have twon streams. Last one seen here in vid looks a bit wonky and didnt clear up. But regardless, two hve broken partially mossing gaskets anyway. Can kind of see in video. Hopefully broken pieces didnt end up in engine when removed fuel rail.

HHR fuel rail /injector cleaning