MAP/MAF readings - help please

[-Mike-]

Hey all,

Trying to track down power problems with an I-ctdi lump (2.2 Honda turbo tractor) in a Honda Accord. I'm wondering if any of you can advise whether the following are red herrings or possible avenues for exploration :

Boost pressure with the engine off according to torque via obd is -0.6 psi. This figure is almost the same with no throttle applied whether the vehicle is moving or stationary. I wasn't aware that diesels generated vacuum and am unsure whether this behaviour is normal.

MAF sensor : The maf sensor is reading 0.6 g/s or around 2 cubic feet a minute without the engine running. Once again, can anyone advise if this is normal behaviour?

Thanks muchly!

 

[-Mike-]

Have you tried unplugging the sensorband going for a spin to see if it behaves better?

I haven't yet. The MAP sensor I think if removed will put it into limp mode though?

 

[-Mike-]

-0.6 psi is fine. That is pretty much atmospheric pressure. I would say even the maf is probably fine, some sensors have a minimum reading that is below what the engine would ever need. What does it read when the car is running?

It still reads around -0.6 psi, sometimes as far as -0.9psi. I had wondered if there was a serious restriction in the breathing system somewhere, but given it still says -0.6 when its off that's unlikely!

Just been to Howards Honda and picked up a service kit for it as I think it needs some love!