Could this be the cause of 1.9 cdti 150 flat spot?

[andreitone]

Astra-H 2004...,Zafira-B 2005...,Vectra-C 2004..., Signum 2004...Z19DT| Z19DTH| Z19DTL,Z19DT| Z19DTH| Z19DTL,Z19DT| Z19DTH| Z19DTL,Z19DT| Z19DTH| Z19DTL

only vehicles with DPF.

Complaint:Some customer may complaint about slightly reduced low end torque after SPS programming with TIS 2000-DVD, version 83.

Cause:Latest SPS software in order to improve DPF regeneration strategey (TIS 2000-DVD, version 83) causes modifiaction of engine characteristic, especially during vehicle acceleration.

[andreitone]

I also found this in TIS:

Vectra-C 2004...2005 Z19DTH MT,AF40 Transmission

Complaint: Bad starting acceleration and bad partial load acceleration below 2000 rpm.

Cause: Insufficient software adaption.

Production: Introduction of modified software in production as of the following VIN: - W0L0ZCF6851112054 (07.04.2005) for manual transmission, - W0L0ZCF686XXXXXX (SOP, MY 2006) for AF40 transmission.

Remedy:
In case of customer complaint reprogram ECU with TIS 2000-CD as of version 62. For vehicles with AF40 transmission a changed software is available as of TIS 2000-CD, version 64. In this case the Engine Control Unit and the Transmission Control Unit have to be reprogrammed.

[winnie2457]

My dpf was blocked upnd had a massive flat spot through the whole rev range an once I gutted the dpf thus has improved vastly and the increase in torque is massive now just pulls all the way to the redline

[justin32]

my flat spot was cured by taking out my penel filter and replacing it with a normal one.