[Komelika]

Hi, I'm using an 04' GSXR1000 engine for a minibuggy project. I bought the engine kit and don't have a donor bike to look at. The AP sensor in the harness has a tube for air pressure. Does the tube go into anything on the bike or does it just mount on the frame and measure the atmospheric air pressure?

Thanks

 

[GSXR Maori]

If it's the one I'm thinking of, it connects to the sensor that's attached to the rear of the airbox. If this is not connected it will run rough and rich.

 

[kwaka10r]

Have a look at an OEM fiche and it will tell you the whole story. Click here.

There is one that has a lug for bolting to the back of the airbox as GSXR Maori said. Part Number:15620-29G00 and this one is the IAP intake air pressure sensor. It connects to a tube that goes to a junction and each throttle body. It measures manifold vacuum/pressure.

There is another one that has a rubber mounting collar, part no.15630-29G10. That is the AP sensor for atmospheric pressure. There is no tube attached to it.

 

[Komelika]

Awesome, thanks guys. The IAP is on the air box. I have that one accounted for. This one is the AP sensor and is just hanging along the harness like all the relays. Appreciate the info!

 

[Chugs]

Check the service manual below.

 

[frank2]

I have a K-5 1000. The AP sensor is mounted under the riders seat, next to the battery. It has a formed nipple which would be considered a formed on tube. It is only about a 1/2 inch long protrusion, molded into the sensor. The IAT sensor is mounted to and protrudes into the airbox itself. Hope that might be some help.

 

[Komelika]

Thanks again guys! Chugs, I'll have to check out the service manual later since my iPad wont open it. It sounds like the ECM uses data from the IAP sensor and compares it to data from the AP sensor as a ambient pressure reference to get a true indicator of the intake air pressure. It makes sense. Without an ambient reference then the IAP is just sending arbitrary information to ECM unless it were preprogrammed for every altitude imaginable.

 

[Komelika]

OK, I have the two sensors sorted out. The motor will only run with the vac tube disconnected from the IAP sensor. It dies as soon as I connect the hose to the sensor. It won't start without priming the throttle bodies. I have replaced the IAP sensor and it doesn't change anything.

If I swap the IAP and the AP sensor in the harness it will start rough and idle rough, but it still dies if I plug the vac hose into either sensor in the AP sensor plug on the harness.

AP plugged in where IAP sensor goes- motor runs rough, but not with vac hose connected

AP plugged in where AP goes- runs but has to be primed to start and will not run with vac hose connected.

No codes indicating sensor failure. Any ideas?

 

[BillV]

We seem to be inching ever closer to the truth but I still don't think that we're all the way there. As best I can tell, the IAP sensor, more commonly referred to here as the MAP sensor, is 15620-35F00 and the AP sensor is 15620-10G00. Those sensors that I've seen are all made by Denso and have the Suzuki PN printed on them in tiny letters. They all seem to have the same electrical and pneumatic characteristics but vary in how they're mounted, where they're mounted, or what electrical connector is used. Apparently someone at Suzuki has made a career out of changing this on every new model/generation rather than standardizing it or even using the same part number for both the IAP and AP on a bike. Perhaps he has his retirement savings in Denso stock.

Every sensor that I've seen has a hose bib. But this is left unconnected for the AP. The IAP is connected to a network of hoses that lead to the throttle body bores. The service manual shows how to test them and lists the voltage vs pressure specs.

If your sensors have the same electrical connection you should be able to swap them as long as you keep the hoses properly connected. In the original wiring harness the key difference is the output lead. The AP is G/Y while the IAP is G/B.

 

[kwaka10r]

Maybe this motor was tuned with the IAP disconnected from the throttle body.

 

[Komelika]

We seem to be inching ever closer to the truth but I still don't think that we're all the way there. As best I can tell, the IAP sensor, more commonly referred to here as the MAP sensor, is 15620-35F00 and the AP sensor is 15620-10G00. Those sensors that I've seen are all made by Denso and have the Suzuki PN printed on them in tiny letters. They all seem to have the same electrical and pneumatic characteristics but vary in how they're mounted, where they're mounted, or what electrical connector is used. Apparently someone at Suzuki has made a career out of changing this on every new model/generation rather than standardizing it or even using the same part number for both the IAP and AP on a bike. Perhaps he has his retirement savings in Denso stock.

Every sensor that I've seen has a hose bib. But this is left unconnected for the AP. The IAP is connected to a network of hoses that lead to the throttle body bores. The service manual shows how to test them and lists the voltage vs pressure specs.

If your sensors have the same electrical connection you should be able to swap them as long as you keep the hoses properly connected. In the original wiring harness the key difference is the output lead. The AP is G/Y while the IAP is G/B.

I came to the same conclusion. The fact that it runs when they are swapped leads me to believe that one is probably bad. The tuning comment is interesting as well. What are the possible issues with running it with the vac tube plugged and left disconnected from the IAP?