[vlvman]

I have been looking at info on our boost sensor, here are my findings. Volvo part # 30622083, Original Bosch # 0 261 230 106 replaced by Bosch # 0 261 230 042. It has a pressure range of 20-250 kPa it also has a NTC sensor (or a IAT) built in with a range of -40* to +130*C.
Electrical pin designations are #1 = ground, #2 = NTC resistor, #3 = +5VDC (from ECU), #4 = Boost signal.
I logged the boost signal with a VOM. These readings are with the 5 year old original sensor on my car and may not be accurate. Also note that I am about 600 feet above sea level. These readings were taken with ignition switch in run position, engine stopped. VOM connected - to pin 1, + to pin 4. Also note an air pressure source was connected to boost sensor through an adjustable pressure regulator.
0 psi 1.55 vdc
1 psi 1.65 vdc
4 psi 1.95 vdc
5 psi 2.05 vdc
10 psi 2.65 vdc
15 psi 3.15 vdc
16 psi 3.25 vdc
17 psi 3.35 vdc
18 psi 3.45 vdc
19 psi 3.55 vdc
20 psi 3.65 vdc
It can be noted from the above that each additional 1 psi results in an increase of 0.1 vdc.
If you have any other info please post it below, ie where to buy and price or other technical info.
I got some of my info here http://www.ontronic.com/produc...t.pdf

 

[FEO]

Re: Boost sensor info (vlvman)

[showing ignorance here]

Isn't this a GREAT way to have a boost gauge without having to T the vacuum hoses, kink them through the firewall etc?

all electric = no leak!! me likey

Grants further investigation!!

http://********************/smile/emthup.gif http://********************/smile/emthup.gif

I have not seen a BG install based on this principle (except IPDs datalogger I guess)....has it been done before?

 

[MightyQ]

Re: Boost sensor info (vlvman)

Nice work... going to see about a redesign for my boost gauge that I have now with this valuable infor.

 

[xman03]

Re: Boost sensor info (FEO)

Quote, originally posted by FEO »

[showing ignorance here] Isn't this a GREAT way to have a boost gauge without having to T the vacuum hoses, kink them through the firewall etc?

Wouldn't an electronic gauge be more accurate; and you don't have to run the vacuum hose through the firewall. In fact you don't have to run anything through the firewall.

 

[MightyQ]

Re: Boost sensor info (xman03)

My boost gauge is connected from the manifold via the boost hose to a computer grade sensor then to the control module then to the LEDs in my cluster. (See IMPConcepts for more info.) and mine is very accurate. You can even ask those who I have built and installed one for.

I'll have to check the parameters of the sensor but I suspect that a new control module will have to be built to accurately intererate the signal from the Bosch sensor.

 

[Shimon]

nice info! thanks!

 

[tmtalpey]

Re: Boost sensor info (vlvman)

Quote, originally posted by vlvman »

... note that I am about 600 feet above sea level. These readings were taken with ignition switch in run position, engine stopped. VOM connected - to pin 1, + to pin 4. Also note an air pressure source was connected to boost sensor through an adjustable pressure regulator. 0 psi 1.55 vdc

The MAP (manifold absolute pressure) sensor isn't reading 0psi at ambient, it's reading your local barometric pressure. 15.5psi is a little high, so let's guess that it reads about 0.5V in a true vacuum (0psi).

If you want a tru "boost" gauge, you'll need to subtract off the ambient baro to read the actual turbo pressure rise. Usually, this is what people want to measure. The ECU, however, wants to see absolute, because it's using it to make mixture and emissions decisions.

Good info, and have fun with it! Be sure your tap to measure the signal doesn't load the value seen by the ECU. A high-impedance digital VOM type reading is best.

Tom.

 

[xman03]

Re: Boost sensor info (MightyQ)

Quote, originally posted by MightyQ »

My boost gauge is connected from the manifold via the boost hose to a computer grade sensor then to the control module then to the LEDs in my cluster. (See IMPConcepts for more info.) and mine is very accurate. You can even ask those who I have built and installed one for. I'll have to check the parameters of the sensor but I suspect that a new control module will have to be built to accurately intererate the signal from the Bosch sensor.

Haha seen it first hand in Nick's car, it's a beauty http://********************/smile/emthup.gif. That was my point that you'd need a control module to take in the signal from the sensor which in turn makes it easy just to use an electronic gauge.

 

[FEO]

Re: Boost sensor info (tmtalpey)

Quote, originally posted by tmtalpey »

The MAP (manifold absolute pressure) sensor isn't reading 0psi at ambient, it's reading your local barometric pressure. 15.5psi is a little high, so let's guess that it reads about 0.5V in a true vacuum (0psi). If you want a tru "boost" gauge, you'll need to subtract off the ambient baro to read the actual turbo pressure rise. Usually, this is what people want to measure. The ECU, however, wants to see absolute, because it's using it to make mixture and emissions decisions.

ah so is this MAP or boost? (I feel like I've read discussions on this before, and I know you (Tom) answered before, apologies if that is the case)

IIRC MAP can be read from OBD (which is even better, not even a high impedance connection is required)

So to the OP, is this MAP or boost? I would have thought that these cars measure boost.....so there's got to be an atm. pres. sensor somewhere in the car

 

[tmtalpey]

Re: Boost sensor info (FEO)

The raw reading from the sensor is MAP - the actual pressure not the boost. Boost, as it's usually defined, is the relative pressure, i.e. the rise over atmospheric. That's somewhat more interesting if you want to know how much work the turbo is doing.

Also note most "boost" gauges plumbed into the manifold have a negative range, to show you when the engine is actually pulling on a closed throttle. Any negative reading is certainly not absolute! But it's interesting from an engine-load perspective and is typically what drivers want to see.

The sensor in question isn't located within the manifold, it's on the intercooler output before the throttle plate. So it won't ever go "negative", in fact it may stay significantly positive even when the throttle flap is closed.

Because these cars use a MAF computation, measuring air mass to compute their mixture response, they don't technically require a MAP sensor to operate. But the MAP is important to monitor turbo performance, and guard against overpressure and detonation. And, the sensor is certainly handy.

You cannot read the R's MAP with standard OBDII protocols (the 0x0B PID). Volvo turbo engines don't provide it, though most Volvo NA engines do. One can, however, read the value with proprietary tools from within the manufacturer-specific ranges. This is not at all easy, or universal across the product line. Very few Volvo-compatible units support this.

Tom.

 

[tmtalpey]

Re: Boost sensor info (tmtalpey)

Oh, re the atmospheric pressure sensor. There might be, but another trick is that the car can readily measure barometric pressure from the MAP sensor just before the engine is started. It doesn't vary much, typically so the initial reading is more than close enough for the purpose. In NA cars, the baro can also be read during WOT periods.

Tom.

 

[FEO]

Re: Boost sensor info (tmtalpey)

ahhhh thanks for the explanation Tom. Neat trick with the abs pressure cal. with engine off.

if only I had a million dollars...and a million hours

http://www.freescale.com/files...A.pdf

Too bad Juve has a boost gauge already

 

[phuz]

Re: Boost sensor info (FEO)

Quote, originally posted by FEO »

ahhhh thanks for the explanation Tom if only I had a million dollars...and a million hours http://www.freescale.com/files...A.pdf Too bad Juve has a boost gauge already

lol, nice.

who needs ECT anyway

 

[FEO]

Re: Boost sensor info (phuz)

Quote, originally posted by phuz »

lol, nice. who needs ECT anyway

LOL I know

I have been an advocate of extirpating that useless temp gauge and reuse it to show boost instead. This gauge doesn't serve any purpose currently

a) It doesn't tell you the actual temps
b) It goes to the middle and stays there, impervious to even engine blowup!!!! (someone had this happen)
c) the engine actually tells you on the DIM when it's too hot, so why have this "on/off" analog gauge at all???
d) it would be even more classy than MightyQs install!!! (hard to achieve)

FTW

 

[vlvman]

I did not expect the conversation to go to boost gauges. This sensor is 2.5 bar, it is corrected for atmospheric conditions. which means its output is 1.5 bar. It's sole purpose is a boost sensor used by ecu to control tcv and measure intake air temp. Thus if it's output is off calibration our boost will be off calibration. In theory if it were replaced by a 3 bar sensor we could raise our boost by 0.5 bar, but the ecu also monitors other sensors and may be able to compensate.

 

[vlvman]

Re: (vlvman)

If we had the voltage readings from a new sensor we could test our sensors when we suspect a fault.

 

[vlvman]

Re: (vlvman)

If we had the voltage readings from a new sensor we could test our sensors when we suspect a fault.
What if we connected the IAT sensor to our dash coolant sensor then we could observe heat soak.

 

[JimLill]

Re: Boost sensor info (vlvman)

Quote, originally posted by vlvman »

I have been looking at info on our boost sensor I logged the boost signal with a VOM.

I had the same thought and Lew Labahn did testing and posted that data a few years ago. I also suggested a build-a-gage method.

Keep in mind that the vacuum gives you a + voltage too.

 

[juve021]

Re: Boost sensor info (JimLill)

I saw my name mentioned here so I'll jump in....
I'm actually, as we speak working on an upgrade to my simple oil temp led project that I currently have in my R. The new display will be an OLED 96x64 display screen hooked up to a PIC to accept readings from a thermocouple. Maybe boost could be displayed as well through those voltages??!?! Another temp monitoring point I was toying with was Haldex operating temp. But yeah, too bad I already have a boost gauge

 

[vlvman]

Re: Boost sensor info (JimLill)

Link to thread please