Mysterious two loose connectors in engine bay + P0238

Hello everyone

Last month i bought a very nice red Citroen C3, with the DV4 8-valve 1.4 diesel engine. Only one small problem..

Everything seems to be running ok with the car except that the check engine light is on. The code is P0238 which "Turbocharger Boost Sensor A Circuit High"
I´ve searched google for hours about this specific code but i can't find anything specific for the DV4 since some engines in the C3 have electrovalves, other MAPs..etc while the DV4 doesn't. (from what i know!).

Also a couple of days ago i noticed a loose connector while i was inspecting under the car, so i removed the airbox and found that two connectors are not connected to anything!

I was hoping that some kind soul maybe could help me identify these two connectors, and maybe share their experiences if they have had the same problem with their C3.

Anything helps!

Thanks, Gaston76

https://www.dropbox.com/s/ra2d4uwdvobt4 ... s.jpg?dl=0

Gaston76 wrote: ↑Mon Sep 03, 2018 8:26 pm Also a couple of days ago i noticed a loose connector while i was inspecting under the car, so i removed the airbox and found that two connectors are not connected to anything!

Hi Gaston76
It's quite common to find plugs that don't go to anything because the same loom is used over several different specifications of the C3.

Gaston76 wrote: ↑Mon Sep 03, 2018 8:26 pm The code is P0238 which "Turbocharger Boost Sensor A Circuit High"

What did you use to read the code?

You may need to connect it to a lexia tool (from ebay) to get the correct description for the P code fault and then checks you need to do, live data etc.

Find out about lexia here to know what you may be getting into

Arfur Dent wrote: ↑Mon Sep 03, 2018 10:04 pm

Gaston76 wrote: ↑Mon Sep 03, 2018 8:26 pm Also a couple of days ago i noticed a loose connector while i was inspecting under the car, so i removed the airbox and found that two connectors are not connected to anything!

Hi Gaston76
It's quite common to find plugs that don't go to anything because the same loom is used over several different specifications of the C3.

pins don't have anything to do with the engine code..
Ohh okay! I thought so since i saw and insert on the underside of the airbox that looked like a connector but there weren't any pins on the inside Then i guess the connectors don't have anything to do with the engine code..

Arfur Dent wrote: ↑Mon Sep 03, 2018 10:04 pm

Gaston76 wrote: ↑Mon Sep 03, 2018 8:26 pm Also a couple of days ago i noticed a loose connector while i was inspecting under the car, so i removed the airbox and found that two connectors are not connected to anything!

Hi Gaston76
It's quite common to find plugs that don't go to anything because the same loom is used over several different specifications of the C3.

I just used a crappy 10 £ generic obd2. I guess it's true after all that all PSA cars are very specific that they only want Lexia tools to diagnose them haha.

If anyone has any experience or suggestions about P0238 then feel free to post.

In the meantime i will bring my car in to my citroen dealer and update you all when i get the results back about the P0238 since it seems to be a very difficult code to solve!

Hello again everyone , small update:

After bringing the car to the stealership they told me the car had three fault codes stored. P0238, P1162 and P0489.
The latter two codes relate to EGR valve, so they replaced the EGR and now the car runs abit better but the original fault code, P0238, is still showing up!!

The only difference now is that i can get the Check engine light to disappear, but only if i plug in my OBD-scanner with the ignition ON but the engine off. If i erase the code with the Ignition in the ON position, the code disappears about 3 seconds after starting the engine.

However it seems that the code likes to come back after about 3 startups, most often when i let the car sit for more than 15 minutes. Also it seems like the engine cranks ever so slightly rougher the times that the check engine light gets triggered. I have also notices that i feel the engine bogging/chugging/trembling when i'm around 1000-1200 RPMs in fourth and fifth gear while keeping a steady throttle. (not accelerating nor slowing down, same RPM).

It feels like this is an electrical issue and i just pray that it isn't some wiring harness issue... to be honest i would like to just rewire the check engine light to the oil pressure light or something so that i can get past the yearly inspections.. but if i don't get this fixed, i will have to either sell the car at a huge loss, or drive it ilegally

If anyone has any freaking idea what to try next, i will gladly listen.

Gaston76

Recently took air box off of my c3 and there are two connectors that plug into air box, one on top and one halfway down. Look very similar to your picture. As for the code, I got the same and anti-pollution fault on car screen, seems prior owner had the air box off and didn't correctly fit the air intake pipe back on the rear of air box. Since putting back together i have no codes showing at all and all has been fine for last few days. Seems a common problem P0238, hopefully this is worth a check.