DIAG for error P0404 - SAAB 93 TTID any idea?

[S0LlDSNAKE]

Hi everyone,

My car (a 2008 SAAB 93 TTID 180 HP Z19DTR - EDC16C39) display error P0404 (Exhaust Gas Recirculation Circuit Range/Performance).
I've remove the EGR valve and see nothing special.... it seems to close well and nothing stuck in it.
I've fit my old EGR valve (when I use to use this one, I had no error code) :
Same trouble, the error code appear again and again after clear the ECU fault code.

To be more precise, the code appear when the valve is supposed close. (the differential between the air flow needed by the engine (calculated from a map?) and the amount of air calculated by the MAF sensor seem to be discordant) I suppose that the ECU think that this difference is made from a not fully closed egr valve and put the P0404.

I've clean the MAF, check any leaks on charge air ducts, nothing seem abnormal.

I guess now that the problem could go from a faulty O2 sensor... (it seem to have a role in the mass air calculation....)

Any idea?

I found an original file (https://www.digital-kaos.co.uk/forum...highlight=TTID) is it possible to conclude how the calculation between MAF / EGR / O2 sensor works ?

Thanks.

[IanBMW]

Corroded/leaky EGR pipe
Clogged EGR system
Check actuator vacuum hoses EGR/Turbo
MAP sensor could also be clogged with dirt or faulty

[S0LlDSNAKE]

Corroded/leaky EGR pipe : Nope, verified
Clogged EGR system : don't think... I could verifiy when I'll remove the EGR
Check actuator vacuum hoses EGR/Turbo : seem work fine.
MAP sensor could also be clogged with dirt or faulty : already cleaned-up.

[IanBMW]

smoke test for vacuum leaks??

[IanBMW]

are you absolutely sure that your EGR valve is moving smooth and free, without notches??

[S0LlDSNAKE]

It was the EGR valve.

The "new one" was a cheap one... and with a real new (brand Dellorto) It's work fine.

Thanks.