Author Topic: cylinder pressure sensor  (Read 52377 times)

Offline BigD

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Re: cylinder pressure sensor
« Reply #60 on: July 08, 2010, 07:15:47 pm »
Aaah, gotcha, thanks!

Offline sly

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Re: cylinder pressure sensor
« Reply #61 on: July 08, 2010, 07:22:26 pm »
has anyone had any luck finding the Toyota part? is it only used in Russia. I even called Toyota but they need a VIN # to get parts.
I have looked at the part places but can find anything.
and all the searches of the 89468-20020 turned up not english.

Offline BigD

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Re: cylinder pressure sensor
« Reply #62 on: July 08, 2010, 09:23:08 pm »
The Russian pages say it's from the 7A-FE (4A got them too). So try 93-97 Corolla or 93-99 Celica.

I'm still searching but found this:

http://carprogrammer.com/Z28/PCM/SAE/2000-01-0932.pdf

Neat highlites:

The SPB pressure sensor operates in a structural load path that is
very linear and well behaved. Cylinder pressure acting on
the combustion chamber creates a force that is elastically
transferred through the cylinder head structure to the
head bolts. A portion of this total force is transferred in
compression through the spark plug boss and has a
magnitude of about 2200 N at maximum cylinder
pressure (6.8 MPa). This provides a reasonable but not
excessive force for sensing. To detect the force, a
shoulder is machined on the inner diameter of the spark
plug boss and the sensor is preloaded onto the shoulder
using fastening threads. To accommodate the sensor, the
cast outer diameter of the upper spark plug boss is
increased about 6 mm. Because the sensor is located
high within the spark plug boss, the sensor has no
detrimental effect on spark plug cooling. The sensor is
responsive to compressive forces applied through the
sensor bottom face (see Figure 3).
A detailed thermal-structural analysis for the sensor and
cylinder head was performed to confirm load path
sensitivity to cylinder pressure and insensitivity to
extraneous loads (Figure 4). Various extraneous loads
are known (valve train dynamics, thermal loads, etc),
however, since loads caused by cylinder pressure are
large, tests show that error signals could be effectively
isolated and minimized (see section on signal validation).
Frequency response of the installed sensor is about 20
kHz, which is adequate for detection of cylinder pressure
including combustion knock.

The advantages of this overall sensing concept are:
1. Direct access to the combustion chamber is not
required
2. Due to abundance of cooling water surrounding the
spark plug boss, sensor operating temperatures and
hot soak temperatures are relatively low (140 C
maximum).
3. Due to mounting outside of the combustion chamber,
the sensor is insensitive to several common types of
thermal errors including intracycle flame arrival
effects and signal drift during engine load transients.

Offline rob@vems.co.uk

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Re: cylinder pressure sensor
« Reply #63 on: July 09, 2010, 04:56:56 am »
Suddenly that has re-sparked my interest in engine management systems.

Offline BigD

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Re: cylinder pressure sensor
« Reply #64 on: July 09, 2010, 11:26:58 am »
Suddenly that has re-sparked my interest in engine management systems.

Hope there was no knock!

Offline sly

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Re: cylinder pressure sensor
« Reply #65 on: July 11, 2010, 05:22:14 am »
Just looking at a spark plug. I have a NGK BKR6EKPB-11 it is much smaller on the top for cops. it seems the smaller size would make for a better time doing the mod.
and with the bump I think it would not be bigger then the normal large plug. this is needed if the plug needs to go down a tube like a lot of DOHC heads.
the 2nd thing I thought of is to use a very tiny drill and drill the outer threaded shell all the way up. The shell seems to be over 2mm thick so it would have to be a very tiny drill.
I think the rest would be the same weld a blob cross drill,re-weld. etc. but get rid of the trench.