evap code PO0443

[dynabill]

I will do that test tomorrow, altho, I kept the hose off all day today driving probably 60 miles, and couldn't get it to pop a code, I guess that is because, it doesn't know the difference between sucking from the canister and sucking pure air. bill

[fixkick]

i hope so. and if true, the canister is constipated. too bad , cheap exlax is not the cure....

another mans horror, in detail, and found on the Corvette forum. some poor sods must make it work or be in EPA H3LL,

you sir, are on track !

[dynabill]

Hey Jerry, Ok I got out there and hooked up back probes to evap vsv, removed bottom pipe and kept my finger on hose to check for vacuum. Had my neighbor start the car, and got no vacuum or voltage from idle. I had him rev to 3000 rpm and still got nothing. No vac or voltage. I than removed electrical connector from vsv and put twelve volts to it. It opened right up with a verifiable clik. I put vac pump on it and verified it was open. I also tested the evap canister by blowing air thru the tank line on evap canister and verified that I could not blow air thru the purge line, with shop air. I pulled hose from intake to evap vsv and verified that there is vacuum from the intake, so that takes the intake nipple out of being clogged. So, i guess that there needs to be a way to trick ecu to power up vsv valve. I am going to go for a drive with vsv line reattached to purge valve and see if i can get ecu to pop the 0443 code again. ok all i have for now. Bill

[fixkick]

all those other tests look good.
the ECU does open it driving, that is when it cant effect driving actions. lots of air and fuel and at 3000 its open, my guess is below that but 3000 is a sure thing.
the motor must be hot. the ISC must be during the idle evap test.

the 3000 is running mode, EVAP. hot motor. the ecu grounds that pin . lt-green-yell.

see it here, purge.
the blue-black is hot all time, key on.
then the green wire (hot ,key on) goes ot ground potential , when ECU grounds it at 3000 rpm.
if if green don't ground out (0v). like that, then that wire is cut. (most likely)

your speed work. and no speedo related, speed DCT failures. no P0500 DTCS? even pendings?
if car is moving under speed it opens that valve. it is not fussy, like the EVAP diagnostic, it just sucks fumes rolling alone.

[dynabill]

Hey Jerry

see it here, purge.
the blue-black is hot all time, key on. Yes it is 12.v
then the green wire (hot ,key on) goes ot ground potential , when ECU grounds it at 3000 rpm. this was also hot, 12.4v
if if green don't ground out (0v). like that, then that wire is cut. (most likely) I'm not sure if there is a test for this, so IDK if this is true

your speed work. and no speedo related, speed DCT failures. no P0500 DTCS? even pendings? Yes speedo works and no pending codes,other than P0443
if car is moving under speed it opens that valve. it is not fussy, like the EVAP diagnostic, it just sucks fumes rolling alone.

P0443 came up twice since my last post. First time I forgot to record freeze, but I got it this time

DTCFRZF O0443
FUELSYS1 CL
FUELSYS2 N/A
LOAD_PCT 16.9
ETC 185
SHRTFT1 1.6
LONGFT1 7.0
MAPKPa 7.7
VSS 0


So at this point, I don't know where to go, I am going to try and get gas cap tested. Because I am sure I wont be able to get a new one locally to replace this one. Hope some of this info was helpful for diagnostics. Bill

[fixkick]

this scans are not moving.

yes, you can test that wire, end to end ,use any voltmeter, key off.
meter on soleniod green and matching ECU green, (not easy with out long test wire)
get near zero OHMS. 0.3 omega sign, auto-ranger or run lowest range ,of ohms , say Rx2 same about 0.3 ohms that is just normal small resistance,
if you you read say 30 ohms the only 6 volts gets to the solenoid, so the Resistance must be near zero.

good evening.