P0236 P0237 boost sensor low input, shudder

**slalomskier** · 08-13-2009, 06:44 AM

Hey guys, i just changed out the rpm sensor and then about 60 miles later something else happened.

Check engine light,

P0236 P0237 boost sensor low input

Car shudders when first starting to accelerate, and may be idling low.

Reset light, inspected the boost sensor, there was fluid in the boost system, is that normal?

where should i look, what should i look for, and any other advice.

**sjonnie** · 08-13-2009, 08:35 AM

You need to replace your boost pressure sensor.

It's on the charged air pipe running from the intercooler to the throttle body. Part labeled 12

**slalomskier** · 08-13-2009, 05:16 PM

A, is it ok that there is fluid in the boost system (in the pipes)?.

B, My car also had trouble starting, and stalled a few times.

I just wanted to make sure the sensor was the only thing wrong.

Thanks,

Josh

**ifnt420** · 08-13-2009, 09:05 PM

Small amount of blow by engine oil in the charge air pipes/intercooler is normal.

**sjonnie** · 08-14-2009, 08:30 AM

Originally Posted by slalomskier

B, My car also had trouble starting, and stalled a few times.

Can't say for sure, if the boost sensor is reporting low it can cause the car to run to lean which would stall it out. You need to hook into the OBDII and look at the fuel trim to see what's happening. To you can also check to see ifi the boost sensor is reporting correctly by threading small wires into the plug and then checking the voltage. There should be 5V over the input wires and 2-5V on the output.

**slalomskier** · 08-14-2009, 08:49 AM

Put in new sensor, in volvo parking lot, and it fixed everything.
Rip off, cost $110, which was cheaper than a few other dealers. I asked for curiosity what they quote to install it. $230 with part. What a rip off. I walked outside with the new part, and it took me 60 seconds to put in, and 2 minutes to clear the code with my OBDII scanner.

Thanks for everything guys

**ronhol** · 08-26-2015, 06:47 AM

This forum was very helpful, thanks to all who contributed.
I was getting a p2036 and p2037 code reads, so I replaced the boost pressure sensor.
But I still get stall-outs on startup only.
So when I start the car, I need to quickly rev the engine, otherwise is stalls.
Not every time, but frequently.
The check engine light went out, but I was still getting codes p2036 and p2037, so I had them reset it last night.
Any suggestions?
BTW, I noticed a small plastic accordion type air duct on the front passengers side of the engine compartment, near the headlight, that is deteriorated and taped up with duct tape.
Any idea what it could be, and could it be causing the stall-outs.

**Antherzoll** · 08-26-2015, 02:19 PM

There are no P2036 or P2037, what are you reading?

P2237 -- ECM-247B -- Front heated oxygen sensor, bank 1 -- Signal missing
P0237 -- ECM-125D -- Charge pressure sensor -- Signal too low

I have no cross reference for P2236 or P0236

BTW, I noticed a small plastic accordion type air duct on the front passengers side of the engine compartment, near the headlight, that is deteriorated and taped up with duct tape.

If this is the charge air pipe then this would be your issue! Unplug the MAF, if it runs better then it's a vacuum/boost leak.

Also year and mileage always helps.

**ifnt420** · 08-27-2015, 12:24 AM

Stall out on startup?
Have you checked your fuel pressure? Just a thought.

**ronhol** · 08-29-2015, 01:53 PM

You are correct, I meant P 0236 and P0237, but I resolved those by changing the Boost Pressure Sensor.
I think I found the problem, there were 2 screws missing on the air intake ductwork, coming off the air filter and going to the turbo, and I put in new screws and it's not stalling.
The other ductwork I mentioned runs into a box containing two silver steel boxes, looks like they may contain electronics??? It comes from the radiator area, looks like an air duct of some type, maybe an inch and 1/2 in diameter. I'm guessing it's to cool the electronic components.
Thanks for the feedback, this forum is a godsend.
Edited to add, 2002 Volvo C70 less than 100k miles.

Originally Posted by Antherzoll

There are no P2036 or P2037, what are you reading?

P2237 -- ECM-247B -- Front heated oxygen sensor, bank 1 -- Signal missing
P0237 -- ECM-125D -- Charge pressure sensor -- Signal too low

I have no cross reference for P2236 or P0236

If this is the charge air pipe then this would be your issue! Unplug the MAF, if it runs better then it's a vacuum/boost leak.

Also year and mileage always helps.