Chevrolet Enhanced codes: #1=MIL P0449 (evap emission vent solenoid valve control circuit), #2=FSC DTC P0446 (evap emission vent system performance), #3=FSC DTC P0449 (evap emission vent solenoid valve control circuit), #4=HISTORY P0449 (evap emission vent solenoid valve control circuit) I've looked at many code links, and watched South Main Auto videos concerning these codes. I'm hoping that I didn't blow the circuit with my tesing, with and without the solenoid plugged in. I might've crossed my probes with battery voltage going to the control wire. Wouldn't the fuse protect the circuit?

 

Ok.

 

Did I offend? Sorry, if so. I guess I'm back to square one, and must replace the vent valve solenoid (whether or not it tested good) with a new one, to be able to know whether the PCM is still sending/receiving signals to/from it. Really worried that the PCM might be damaged by my testing (when I crossed probes). I would be able to see that on Torque Pro (my scan-tool doesn't), but my bluetooth dongle ceased communicating with my phone. I'm buying another dongle. After that, I just don't know....Thanks for the offered help, so far.

 

No offense, I've run out of input.

 

I continued my testing using TORQUE PRO, and OBD LINK (new app, since I replaced my sometimes erratic BAFX dongle- though very reliable 'til just lately- with the OBDlink LX dongle); the O2 test completed, and I only needed to solve the evap test problem remaining. I ordered a new evap vent valve and jumper from Amazon (ordered twice, first shipment never arrived), and after installing it, the dtc's vanished. So, I restarted drive cycle testing. Now, with limited mileage, all tests are completed (according to the scantool, and Torque and OBDlink apps- the apps also show live data of the O2 sensors and evap systems working fine-except the O2 and evap. I had to stop to refuel (tests must be run between 3/4 and 1/4 tank full). When I started the panel after filling, and put it in reverse, my DIC displayed service engine, service traction, TPMS, etc. I shut off the engine, restarted, and the DIC was clear. I returned home, with the Torque app still running. Now both apps and the scantool show o2 an evap tests not complete, and no dtc's present. However, the 3100i scantool shows (in Chevrolet Enhanced Codes, only):

Once more, I watched live data on both Android apps, showing systems functioning fine. So, was the sudden appearance of weird dtc's just a glitch, or signifying something bad coming? Or do I just continue to "drive test" until the emission tests complete. I'll get a second 30-day temporary permit tomorrow.

 

Confuses me. Did the DTC go away because the battery was disconnected or because "problem solved"? Is the CEL on?

The fancier the scanner the more likely you get "phantom" DTCs.

 

The CEL went away when I restarted the engine; I didn't clear any codes, nor disconnected power. The phantom codes never appeared on Torque or OBDlink apps, only on the Innova 3100i (a mid-range scantool, $79 on Amazon), after I returned home.

 

As long as there is no CEL and no current codes you should be OK.

Those mfg specific codes are not reliable since they may be for Chevrolet, but Impala not all Chevrolet. Basically, ignore them unless they seem to be causing the problem. I don't think many of them actually apply to HHR. Yours may mean that you used the cruise control then turned it off by stepping on the brake,

or the connector to the TCM is faulty.

" put it in reverse, my DIC displayed service engine, service traction, TPMS, etc." makes me wonder about a loose wire under the hood.

 

I was using cruise control the previous day, on and off, to better maintain speed without downshifting on hills, and leaving it set to 60mph. I never turned the switch off. I can't say whether or not if it was on yesterday. However, when the CEL's occurred, I had started the car and instantly shifted into reverse, faster than I usually do, to avoid a truck-trailer coming too close in the service station. I backed out of the way, then saw the CEL's, and restarted. Reminds me of when I started my 2500HD, and shifted into drive and hit the gas too fast, and received some message on the DIC (I don't remember what). I "limped home" through the entry gate I had been waiting at, and parked. When I restarted it moments later, driveability was normal, no messages were displayed, and no problems since (in 2006 or 2007). I'll drive thevHHR again today, and see what happens, if anything, out of normal. I need to run some miles on it, since I overfilled the tank to more than 3/4 needed for the evap test.

 

I forgot to check the scantool for ABS codes yesterday. It had two:

None of the above codes reappeared on the DIC, nor on either of the Android apps, after my test runs today. But the scantool still has them in memory. I suppose they will go away after awhile, with no re-occurrences. I was able to drive over 25 miles at a constant 70mph, and that finally completed the O2 test. Only the evap monitor testing remains incomplete. The scantool IM shows "yellow" as a may pass condition, but the OBDlink app says "ready for inspection", though the test is incomplete. But, the TexasDPS website says:

That said, even though I just paid another $27.50 for a second temporary 30-day permit, I'll forego anymore "drive cycle" test runs, and go straight to the inspection station before any more phantom codes appear. Once I get my inspection/registration sticker, then I'll try to complete the evap test. ...and also find out why my handbrake chimes quit working when the first CEL happened 18 months ago....