What is DTC P0106 telling me?

[Dieselnerd]

P0106 - Manifold Absolute Pressure Sensor Performance is what my code reader is telling me.

I have been getting a P0106 every couple of weeks, usually on the second start of the day. It goes away after 3 or 4 restarts. Just annoying but I'd like to fix it. I have an extended warranty but I don't want to spend $100 deductible if it's an easy fix.

I would appreciate hearing from anyone that knows what normally causes this code and if the sensor is going bad or just dirty. Thanks in advance for your help

 

[lpennock]

Turbo speed sensor is going out.

 

[Dieselnerd]

Turbo speed sensor is going out.

I'm going to replace the MAP sensor first since that's what the DTC calls for. If that doesn't work it's going to the dealer.

 

[lpennock]

I'm going to replace the MAP sensor first since that's what the DTC calls for. If that doesn't work it's going to the dealer.

It's a derived code. The manual is wrong.

 

[Dieselnerd]

Thanks for the advice and video.

 

[lpennock]

BTW: Nice camper setup. I have a Eagle Cap 950.

 

[Dieselnerd]

Thanks for the camper comment, we use it all summer and the fifth wheel is only used for winters down south..

Back to the P0106, I have been doing a lot of reading on the Internet and various diesel forums.

My engine check light doesn't come on when I am driving. It comes on at the initial key on diagnostic check. As I've learned, at key on the atmospheric pressure, turbo pressure and intake pressure are compared. If they don't match, the check engine light stays on when you start the engine. I don't think this has anything to do with turbo speed since when the diagnostic fails the engine is not even running. According to what I've read, this is usually a bad/dirty MAP sensor or wiring and the first thing you are supposed to check is the sensor.

Based on that, I'm still going to change the MAP sensor first and I have one coming from Geno's.

If that fails it goes to the dealer for the much more expensive fixes because I do have an extended warranty that covers everything with a $100 deductible.

 

[lpennock]

Sounds reasonable. Might try one of the ebay speed sensors if the map sensor doesn't solve the issue. For under $15 and about 1hr could be worth a try.

https://www.ebay.com/itm/68039104aa...a0GZY:sc:USPSFirstClass!85249!US!-1:rk:1:pf:0

 

[sag2]

I suppose the speed sensor could be reading incorrect and the ECM thinks the turbo is actually spinning faster or slower than it really is. Obviously from the video it repaired that guys truck. Here is the actual diagnostic so you can check it for yourself. Remember that if the fault is not active at the time you check it the test results will lead you to the sensor. The diagnostic gets close by having you check the turbo for damage, so it seems logical that the bad speed sensor could make the ECM think the turbo is actually bad.

 

[Dieselnerd]

Thanks sag2, lots of good info in that pdf.

 

[Dieselnerd]

I replaced the MAP sensor. So far so good. If the P0106 doesn't come back in a couple of weeks I'll know it's OK for sure.

The old sensor was covered in a layer of greasy crud, hard to see how it even worked as good as it did. It must be designed to work in a dirty environment.

 

[Dieselnerd]

Just an update, it's been a couple of weeks now and the P0106 has not come back so I think the new MAP sensor took care of the problem.

 

[lpennock]

Great. Thanks for the update.

 

[jhenderson]

I replaced the MAP sensor. So far so good. If the P0106 doesn't come back in a couple of weeks I'll know it's OK for sure.

The old sensor was covered in a layer of greasy crud, hard to see how it even worked as good as it did. It must be designed to work in a dirty environment.

Not running an oiled air filter, are you?

 

[Cummins12V98]

Not running an oiled air filter, are you?

GOOD question!!!

 

[Dieselnerd]

No, I only use stock filters from Geno's.