Code P1343

[loudspeaker69]

Hi all,

I have a code for Service Engine Soon that reads to be P1434 - Diagnostic Module Tank Leakage (DMTL).

So I changed the Fuel Tank Vent Valve (DMTL).
Code came back after 100miles.


When I read it this time, it says
- P1434
- P1434 PD (Pending?)


Any advice on what else it could be?
Thanks in advance!

[lemoose]

Pretty sure i had the same code a couple weeks ago. Its your fuel tank breather which hangs just under your airbox. Part was under $50 and fairly easy to replace within 15 min. Just remove the top air filter cover and you should be able to see it and reach it.

Edit:
disregard! thats a different code! Check your gas cap

[loudspeaker69]

I changed the gas cap.

That didn’t do anything.

[erickhoyos]

Secondary air pump

[loudspeaker69]

Secondary air pump

Does this typically mean its faulty - time to just get rid of it?

Wonder what the downsides are if not running the secondary air pump?

[Tbonem3]

Does this typically mean its faulty - time to just get rid of it?

Wonder what the downsides are if not running the secondary air pump?

None, really. Not heating the cats up as quickly as normal. Might smell a little more at first. You'll need it to pass smog, tho, usually.

[loudspeaker69]

That makes sense, as I felt there was extra emissions whenever it had a cold start.

OBD II doesn’t have a smog test / sniffer in my state.

If not mistaken it’s all through the OBD.

[loudspeaker69]

If I clear the code and pull the fuse, will I essentially not see any code related to the Secondary Air Pump come up again ?


Also,

Would this code cause erratic idle ?

[Arith2]

There's an issue sealing the fuel tank. Could be a leak at a line or faulty valve. The secondary air pump literally has nothing to do with this system... It's not even on the same side of the car. Essentially what happens is fuel vapors must not be allowed into the atmosphere(per EPA overlords and hydrocarbon gases are flammable) so the purge valve will allow vapor to pass through your charcoal canister which catches the vapor. Then the air will either get vented to the atmosphere or into the intake. I'm pretty sure all combustion cars now have it going into the intake and electric cars are vented to the atmosphere for obvious reasons. I thought the SAI might have been a troll post but maybe not which is fine. It's really hard to diagnose something if you're not sure of the idea behind it. Porsche literally uses vacuum actuated everything so I'm pretty well verses in test this crap. Pretty soon they'll find a reason to send vacuum lines to the radios. Smoke test the system and test the solenoids. You probably have a leak.