My check engine light came on yesterday on my 2002 Volvo s40 and I put the OBD II on it. The code is P0234. What is the issue here? Can I determine cause by just how car runs?

Any help appreciated. Thanks in advance.

Respectfully,



Newport_j

 

Enter the code in the search box in this forum.
You will get results like this thread
https://volvoforums.com/forum/volvo-...de-only-66496/

From Alldata, regarding that code...
Signal too high:

• The boost pressure control (BPC) valve has stuck in the closed position
• Leakage in the hoses for the boost pressure control (BPC) pressure regulator
• Defective boost pressure control (BPC) valve pressure regulator
• Defective mass air flow (MAF) sensor.

Martin

 

Thanks.


I have been having trouble with the MAF sensor. Is this the most common problem with p0234 codes or is it something else?


Thanks in advance.


Respectfully,


Newport_j

 

How do you mean you've been having problems with the MAF sensor??
It needs to be tested, or you can unplug it and go from there , after you see what happens then.
The BPC is also a likely culprit.
It's next to impossible to diagnose over the internet, and not 100% right all the time when the vehicle is in someones hands who knows what they are doing

Martin

 

What is the part number for the BPC. Where is it located on a Volvo s40? I do not know whether to replace it or repair it.


What is the part number of name for the BPC the boost pressure control valve?


If it is cheap and easy to replace then I should replace it. The CEL light comes on periodically and goes off periodically. I am just wanting tis repaired.


Any help appreciated. Thanks in advance.


Respectfully,




Newport_j

 

 

I guess the logical response for this code (P0234) is to replace the Boost Pressure Valve. That seems easy enough.


Now if that does not shut the light off then maybe I should look at number 2. which is the hoses that connect the Boost Pressure Control valve. Is that correct,


The final thing to check is the MAF sensor. Correct?


Respectfully,


Newport_j

 

my work sequence would be a) check hoses/boots and vacuum lines b) clean MAF, idle valve, intake with MAF cleaner c) test what parts you can.. ie measure voltages on the MAF etc d) order/replace most likely suspect... just be careful with MAFs - some models are very sensitive to after market "near" fits. You may want to go OEM if it turns out to be the MAF or shop where you get a "guaranteed fit"

 

I will start by replacing the boost pressure control valve. I just need to know the part number for one for a 2002 Volvo s40. Also, does this valve come with the hoses or do they need to be bought separately?

Thanks in advance.


Respectfully,

Newport_j

 

Take a look at the one from IPD. (I don't get anything from them)

(BCS) Boost Control Solenoid GENUINE VOLVO 115605 9473212

It looks like you do not get hoses. You can always call their tech department to get helpful advice.

 

Okay, it looks like the correct part, but I do not get hoses.


The question is what type of hose do I need and how long should it be?


I found a sample hose at the same website you showed me, it has a part number 121613.


It is 5 mm ID. Is his the right one for a 2002 Volvo s40?


Respectfully,




Newport_j

 

diagrams etc can be found on some of the dealer web sites ie tascaparts.com and volvopartswarehouse.com. I also find the folks at FCP good for tech questions.

Note VPW shows the valve for $66 and the hoses as needed.

 

What is the phone number or website address for FCP?


Respectfully,


Newport_k

 

https://www.fcpeuro.com/Volvo-parts/

Newport_k, Please stop double spacing between sentences. Just takes up extra room.

 

Damn!


I thought that I had it. I installed a new BPV on my 2002 Volvo s40 and it seemed to work.


The car had pep and it did not display any check engine light. That worked for almost 3 weeks. Then - boom - the check engine light came back on.


I have not checked the code, but it is probably p0234 or p0101.


I guess the next job is to check the MAF sensor hoses and to clean the MAF sensor.


Is this a logical step to make. As I said I replaced the BPV, but the check engine light came back on after about three weeks.


Any help appreciated. Thanks in advance.




Respectfully,




Newport_j

 

did you check for vacuum leaks or leaks on the boost side of things? Another possible cause could be the MAP sensor (air pressure sensor - not the MAF air flow sensor which meters fuel to air ratios)

 

I will check what you stated. thanks ofr the heads up.


Respectfully,




Newport_j

 

What is a good brand and price for the MAP (as you said it is not the MAF)? I have seen prices all over the place.


Respectfully,


Newport_j

 

Re shopping for a MAP sensor: eeuroparts.com has a Bosch for $50 and Volvo OEM for $100. If you want Volvo OEM, Tascaparts.com is probably the best price.

 

I am not sure if there is a difference between the Bosch MAP sensor and the original equipment Volvo MAP sensor except in the price. Is there?
Also, where are the instructions on installing the MAP sensor?

Any help appreciated. Thanks in advance.

Respectfully,

Newport_j