I have 2002 VOLVO S80 T6
I get codes p0235 and p0236 could anyone please tell me which sensors to check I know it is a boost circuit problem.I did some research volvo told me there is a solneiod valve part# 9473212 which some call boost presure valve and also map sensor part#9125462.I also disconnected map sensor and drove car.Codes p0236 and p0238 came up.Any advice please of which sensor to change first if its any of these two.I know i might have to change both to find the one that is bad.I also read here something about map sensor.
Thanks in advance for any help
Elliot

 

Sounds like the MAP sensor.




If you think maybe the boost pressure valve, here is the pic/location for that.

 

Ok I had found the presure boost valve sensor already and disconnected that only I get codes P0236 AND P0243 any advice now still think map sensor?
Just a recap when everything connected I get codes p0235&p0236. When I disconect map sensor only I get codes p0236&p0238
When I disconnected presure sensor valve only I get codes p0236&p0243
Thanks

 

Doesn't sound like the valve is the issue as the P0236 stays constant. Are you clearing the codes after each disconnect to see which ones return? If you just start unplugging things and re-plugging them in you're going to keep getting a lot of the same codes if you don't clear codes in between.

 

always clearing before and after disconnect after I put everything back and clear I get p0235and p0236

 

I would put my money on the boost sensor aka MAP sensor. Which is the very top pictured sensor.

The best thing to do is check and make sure it's connected and not corroded. The codes are for a circuit fault as if it were not connected. That leads me to believe it's an electrical issue and not a mechanical one. If you have determined the connection looks good, then if you have a scan tool that can read the boost pressure; you need to see if it's within specification.

Normal pressure should be 1013hPa
Out of range would be +/- 140hPa from normal


BTW your codes are as follows:

P0235 Turbocharger Boost Sensor A Circuit Malfunction
P0236 Turbocharger Boost Sensor A Circuit Range/Performance

 

The best thing to do is check and make sure it's connected and not corroded. The codes are for a circuit fault as if it were not connected. That leads me to believe it's an electrical issue and not a mechanical one. If you have determined the connection looks good, then if you have a scan tool that can read the boost pressure; you need to see if it's within specification.

Normal pressure should be 1013hPa
Out of range would be +/- 140hPa from normal


BTW your codes are as follows:

P0235 Turbocharger Boost Sensor A Circuit Malfunction
P0236 Turbocharger Boost Sensor A Circuit Range/Performance[/QUOTE]

[QUOTE=BradF80;385695]I would put my money on the boost sensor aka MAP sensor. Which is the very top pictured sensor.

I will probabley take chance and order map sensor The first thing I did was clean conecter on map sensor with carb cleaner and there is no corrision.What threw me off was when I completeley disconnected map sensor I get codes p0237&p0238 I also read that one person changed 2 map sensor and nothing till he replaced coilpack on cylinder #1 but that was on 2004 s60 .
Thanks for all your help

 

That would be odd if it was a coil pack somehow haha. The other two codes you had were also for the boost pressure sensor. Those codes are signal codes which kind of makes sense since the computer is no longer getting signal when you disconnect it.

If you're not into diagnosing it, that's the part I would throw at it first.

If you still get a code. then you might have an actual pressure problem which could be caused by the boost control valve (the second picture) or the turbos not spooling up right or an air leak in your charge pipes. 1013hPa is 14.7psi which is your stock boost pressure. You'd have to get a boost pressure gauge and check to make sure mechanically the pressure is correct.