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Discussion Starter #1 (Edited)
Message from the HFTC Parts Commission the Netherlands (date 24-03-2013).

Pb-sensor replacement.

Dear Turbo colleagues, the HFTC Parts Commission has searched for a Pb-sensor replacement. This because the original ones start to give technical problems and Honda is no longer supplying the sensors.
After searching on the Internet, inquiries at the various motorcycle importers, visits to car- and motorcycle breakers, etc, we have put some sensors at a workshop test.
A few selected sensors have afterwards been tested on a CX500T and CX650T followed by a test on a Dynojet test-rig provided with exhaustgas measuring equipment.
The best results came from a Suzuki MAP-sensor.
Two Toyota Map-sensors showed almost identical characteristics as the Suzuki sensor*
Based on the testresults, the HFTC Parts Commission is confident to recommend the Suzuki sensor as a Pb-sensor replacement.
The Toyota sensors are very close to the Suzuki sensor so also usable.

Below the details of the Suzuki-sensor.

Brand: Denso.
Type number: 100798-5630. Suzuki orderingnumber: 15620-35F00.
Suzuki description: Sensor Boost, IAP (Inlet Air Pressure) sensor.


Below the details of the two Toyota sensors.

Brand: Denso
Type number: 100798-4530 and 100798-5250 Toyota orderingnumber: 89420-16080 and 89420-02010

New Suzuki sensor.
Via a motorcycle dealer, newprice 198 including VAT (Motoport, December 2012).

New Toyota sensors.
Via a cardealer, newprice ca 480 including VAT.

Connectortype: DJ7036F-2.2-11/21.

Used sensor and connector.

Apart from buying a new sensor/connector one could think of obtaining this (most probably cheaper) material from a motorcycle-/car breaker.
Be aware that apart from the sensor a connector is needed. This connector is normally part of a cable-loom/wire-harness. Furthermore the sensor has to be checked for the correct type number. A different type number means a different characteristic!!!!

The mentioned sensor-type is fitted on the following Suzuki motorcycles:

Type Year of production.

AN 650 2003 - 2006
GSXR 1000 2001 - 2004
,, 750 2000 - 2003
,, 600 2001 - 2004
SV 1000 2003 - 2007.

The Toyota sensors are fitted on the Toyota Starlet 96 - 99 and Corolla 95 - 04.
Sometimes sensors are offered on E-bay etc.

Suitable used connectors are (also) found on the various car types such as:

Toyota Corolla 1990 - 1997
Toyota Corolla 2004 - 2005
Subaru 1995 - 2002
Suzuki 1995 - 2002
Mazda 1995 - 2002, etc.

The Suzuki sensors are also available on Ebay, second hand, and goes for about 10 to 40 dollar.
You will need a connector for the Suzuki sensor. You can find them in Toyota cars at breakers second hand.


Any questions?? Send me a mail.

Regards Leo Knijnenburg and Ko Maljaars
Parts-commission HFTC the Netherlands
Honda First Turbo Club founded 1986
 

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Leo and Ko, thank you very much for your research and hard work. That is a real effort of love for these bikes and I really appreciate your sharing with us. I am lucky to have the owner of the largest Toyota dealer in the state as a neighbor and I get pretty good access to his parts department by this. I am going to check to see what our local prices are (no VAT) and see if we can help some folks over here. In case you do not know him, I would suggest you contact my friend Pim on this forum he lives near Amsterdam) as he has a wealth of ideas about these bikes. Thank you again and please keep us posted on your progress. We will do the same here.
 

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Excellent information. I created a cut and paste, and added this page to my tech manual, and added a few Google Images of the Suzuki/Denso sensor to the document. A few years ago, I too experimented with replacement MAP sensors to substitute for PB sensors. I read the specs on the VW Jetta unit. I bought one at a junk yard for about $10. I then rigged a harness temporarily to the PB sensor wiring. The bike started and idled OK, however, stumbled during while throttling, which I'm sure was due to the detailed power band pressure differences between a Jetta and a CX Turbo. I took a small clamp and applied various crimping pressure on the hose (simulating orifice tubes & sizes), and at a few points it actually ran fine. I just never pursued it further. I was convinced that with some tweeking, and making an exact size orifice tube, then it may have worked. We will need this kind of "out of the box" thinking, as our precious bikes continue to age, and parts become scarce. Thanks again for the research!
 

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I agree, great news!



@HomerRod: Your experiment with clamping the hose sounds like something an adjustable aquarium air valve could help with, preferably brass of course. The ones used to regulate air flow from an air pump to the air stones and stuff. That might open up even more possible sensors.
 

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Discussion Starter #6
Thanks all for your compliments and I think we deserve it!!!

Eventually, after many tests of several (10) different sensors, we discovered the Suzuki sensor was matching.

We shared this information all over the world so everybody could take notice of it.

So we hope someone will come with a solution for the bearings and piston-rings one day.



By the way: Pim Pouw is a member of our club.
 

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Thanks all for your compliments and I think we deserve it!!!

Eventually, after many tests of several (10) different sensors, we discovered the Suzuki sensor was matching.

We shared this information all over the world so everybody could take notice of it.

So we hope someone will come with a solution for the bearings and piston-rings one day.



By the way: Pim Pouw is a member of our club.


I agree; well deserved complements!

This research will greatly benefit the CX Turbo community. Now that there is a suitable alternative to finding

an actual PB sensor, we will not be at the mercy of the online and salvage yard gougers. I actually had a quote of $600 from a salvage

yard a few years ago when I needed the sensor. Crazy! Luckily, another forum member had a spare and sold it directly to me for $45.

I am convinced that any sensor on the bike can be replaced with an automotive alternative, with only minimal tweaking.

I bet that a modern Honda TPS (throttle position sensor)

can be adapted to our bikes as well, as the voltage specs seem similar. We already know that the fuel pump can interchange, too.

I've found sites that specialize in ECU repair also. These things will simply extend the lives of our bikes. Great news.

Thanks again for the research.
 

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Discussion Starter #8 (Edited)
I agree; well deserved complements!

This research will greatly benefit the CX Turbo community. Now that there is a suitable alternative to finding

an actual PB sensor, we will not be at the mercy of the online and salvage yard gougers. I actually had a quote of $600 from a salvage

yard a few years ago when I needed the sensor. Crazy! Luckily, another forum member had a spare and sold it directly to me for $45.

I am convinced that any sensor on the bike can be replaced with an automotive alternative, with only minimal tweaking.

I bet that a modern Honda TPS (throttle position sensor)

can be adapted to our bikes as well, as the voltage specs seem similar. We already know that the fuel pump can interchange, too.

I've found sites that specialize in ECU repair also. These things will simply extend the lives of our bikes. Great news.

Thanks again for the research.
I am sure there are many parts available for the Turbo from other manufacturers. The problem is to find them.

With the Suzuki sensor we have replaced two sensors in one, the Pb and P1 which are the same!

A throttle sensor is a very easy to find. It's no more than a potentiometer with a specific resistance. Luckely they seldom fail. So is the crankshaft sensor.

The other sensors like the P2 and Pign are next to search.

For the Ne-sensors we found years ago the LX579.

So we are on the right way to preserve our beloved turbo's
 

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Well deserved, indeed!

I was well into a design for a signal conditioner to use the Freescale MXP4250 sensor when I found your information.

I immediately ordered a Suzuki sensor, which arrived yesterday.

I was able to confirm that my original sensors are probably good, as they "almost" exactly match the Suzuki sensor within .1V or so.

I'm still going to try it on the bike and see if the light load performance problems go away.

If it doesn't improve, I'm ready to give up.



Thanks again.
 

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Discussion Starter #10
The major problem with the Pb sensor is that when you do static measurements it will show no derogations.

When you do a dynamic test or drive the bike it does. I think because of their age they don't follow the pressure fast enough so you get wrong output to the ECU.

You also have to know the Pb works only till about 3000 revs. So if you have a bad Pb the bike will perform good above 3000 revs and bad below.

Let me know how it goes with the Suzuki sensor, I'm very curious if it was the problem.



Good luck.
 

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I think you're right about that.

I always suspected that mechanical fatigue inside the sensor had something to do with it. It doesn't seem to show up at all with static or near static tests.

I've never had another sensor to test with until now. I hope sensor technology has progressed a bit in 30 years.

I'll let you know how it works out....
 

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...

I was well into a design for a signal conditioner to use the Freescale MXP4250 sensor ....


I would suggest not giving up on that endeavor since there's no guarantee replacements for other sensors can be found.



A microcontroller and generic sensor operating in the desired range with the MC outputting PWM into a voltage converter referencing ECU ground and voltage should work.

You could use the PWM signal to switch a transistor or mosfet to achieve voltages greater than the 3V3 or 5V0 most microcontrollers operate at.
 

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I'm leaning toward analog, although a programmable digital sensor has it's sexy side.



But, the Suzuki sensor fixed my problem! I'm so happy, it brings a tear to my eye...





This turbo has been running like krap since I bought it (the first time) in 1993! I replaced the Pb sensor then with a "new" one, which was still available then, and apparently it was bad, too. I sold it because I got tired of trying to find the problem , and when I bought it back last year, I started in again.



I mounted the sensor on the R bolt of the original sensor, and it fits just fine.



Thanks be to Leo Knijnenburg and Ko Maljaars.

I am forever in your debt.



I'm going boosting tomorrow, even if it's too cold!
 

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Discussion Starter #15
I'm leaning toward analog, although a programmable digital sensor has it's sexy side.



But, the Suzuki sensor fixed my problem! I'm so happy, it brings a tear to my eye...





This turbo has been running like krap since I bought it (the first time) in 1993! I replaced the Pb sensor then with a "new" one, which was still available then, and apparently it was bad, too. I sold it because I got tired of trying to find the problem , and when I bought it back last year, I started in again.



I mounted the sensor on the R bolt of the original sensor, and it fits just fine.



Thanks be to Leo Knijnenburg and Ko Maljaars.

I am forever in your debt.



I'm going boosting tomorrow, even if it's too cold!
I'm also very happy it works well . Now you can really enjoy your turbo. Mission accomplished.
 

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So, where's the video of it running balls-out?
 

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Funny you should mention video...

My son just bought a GoPro and a package of helmet mounts....



It didn't help the problem when I swapped Pb and P1, so that means P1 has less-than-stellar performance as well. I think I'll replace it, too, even though it's under far less stress than Pb.



Stay tuned for further reports....
 

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Had my maiden voyage last evening after the new Suzuki MAP sensor.

I can tell you, if your turbo has ANY drivability issues like coughing, hiccups, hesitation, backfire, poor throttle response, etc., at light loads....

CHANGE THE MAP (Pb) SENSOR!

I don't remember even the turbo I bought new running this well. It's absolutely smooth, hot or cold.

Probably should change it as a matter of course. It may improve gas mileage or something you don't even know you have.

What an awesome discovery!

I ordered another one off ebay yesterday to do some testing on the old Pb sensor and then to replace P1.

Now to test the wastegate actuator. I want all the boost I deserve.

It's gonna be a good summer!



Thanks again, Dutchturbo team!
 

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Had my maiden voyage last evening after the new Suzuki MAP sensor.

I can tell you, if your turbo has ANY drivability issues like coughing, hiccups, hesitation, backfire, poor throttle response, etc., at light loads....

CHANGE THE MAP (Pb) SENSOR!

I don't remember even the turbo I bought new running this well. It's absolutely smooth, hot or cold.

Probably should change it as a matter of course. It may improve gas mileage or something you don't even know you have.

What an awesome discovery!

I ordered another one off ebay yesterday to do some testing on the old Pb sensor and then to replace P1.

Now to test the wastegate actuator. I want all the boost I deserve.

It's gonna be a good summer!



Thanks again, Dutchturbo team!
 

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OMG! It runs Soooooooooooooooooooooooooo good! So smooth, so creamy....



Sorry, I'm ok now....
 
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