Air pressure sensor causing RPM to surge

[topazsparrow]

I'm not sure if it's due to the FTECU Auto-tune package (it was fine for a week before I took the baffle out of the akra), or if it's because I took the snorkel out, but my bike hasn't been able to hold a steady idle for a while now.
 
It'll dip down to 1000 rpm frequently and actually caused a stall a few times.
 
I thought it was the TB sync, but discovered after removing the line to the intake pressure sensor that the surging went away (and the CEL came on, but that's to be expected). You need a special tester harness to test the sensor, so I wanted to check here to see if anyone else has run into a similar idle surging issue with either the FTECU Auto Tune package or the removal of the snorkel.
 
 
 

[norcal616]

I got better tuning results with baffle in... something about getting smoother AFR readings at the wideband sensor
 
Myself and another member have been trading PM for last 4-5months with running the auto tune from PVC...many diffrent experiments and brainstorming...
 
Check the clutch safety switch...

[farble]

I had surging at idle, and fault code 13, which is the air intake pressure sensor. Fortunately got it to the dealer just before warranty expired. They eventually tested that sensor and found it was bad. I was wondering if there was any mention of the problem on this forum, and found this posting.

 

 

It took the mechanic a long time to diagnose the problem. He was distracted by all the accessory wiring I added, for usb charger, heated grips, plug for heated vest, relay. He felt he had to check all that first. Service manager called to tell me they had put $200 labor into it already and only found a problem with the connector to the accessory circuit. I immediately went to the shop to see what they were talking about. I figure the mechanic pulled the wire out of the connector when disconnecting it for testing.  I remember having a problem building that connector with the pins not clicking into place. The mechanic had a kit for making those connectors, so he remade it.

 

After they put it all back together, and found the engine still didn't run right, they discovered the sensor problem and said there would be no charge for the service.

 

If I was the mechanic, I probably would have checked my wiring first, too. I did that when the accessories stopped working. Pulled it all apart and then discovered that a short in the USB charger itself was blowing the fuse. My wiring was ok.

[DewMan]

48 minutes ago, farble said:

If I was the mechanic, I probably would have checked my wiring first, too. I did that when the accessories stopped working. Pulled it all apart and then discovered that a short in the USB charger itself was blowing the fuse. My wiring was ok.

I fear the reason they may have checked all your wiring first was so that if they were lucky enough to find the issue there... it wouldn't be covered under warrantee and they could stick you with the bill.

[farble]

7 hours ago, DewMan said:

I fear the reason they may have checked all your wiring first was so that if they were lucky enough to find the issue there... it wouldn't be covered under warrantee and they could stick you with the bill.

The service manual says to "check the  wiring harness" before testing the sensor. I hope the dealer gets paid by Yamaha for warranty service, but maybe less than what they would charge me.

[DewMan]

1 hour ago, farble said:

The service manual says to "check the  wiring harness" before testing the sensor. I hope the dealer gets paid by Yamaha for warranty service, but maybe less than what they would charge me.

I'm sure the manual does, but when I was a mechanic I'd have swapped out the sensor first to see if the code goes away and if it didn't, then start trouble-shooting the harness. But then it was 30 years ago when I was a MC mechanic so take that with a grain of salt. ✌️ Glad they were able to resolve the issue for you at no cost to you.

 

OP, Sorry for the hijack.  

Edited November 4, 2017 by DewMan

[CarGuy7a]

I doubt that removing the snorkel is causing your problems. There's alot of us here who have removed it without any adverse affects. I would say you have a bad sensor if the problem stops when you unplug it.

 

Here's a snapshot of the manual on how to test it. I'm not sure if you can do this with a regular mutlimeter or not but it's worth a shot.

Edited November 5, 2017 by CarGuy7a

[Jakey420]

Does anyone have a location on the air sensor? I my engine light came on while riding then I got the 5d 13 code so I wanna make sure it didn't come unplugged before I buy one off ebay

[ElGonzales]

Not a good picture, but I think you can see the black bottom of the sensor where I put on the transparent hose. Left side of the bike, green arrow is pointing to it.

 

View from the other side, fuel tank is removed:

I've played around with some of these aftermarket sensors. I have ordered some cheap Chinese ones which are looking absolutely identical to the original Yamaha sensor. The specification and the behaviour should be the same but I never had a chance to compare them directly 

 

FYI, this is the output of such a MAP or air pressure sensor (how Yamaha calls it). Voltage in relation to connected negative air pressure. Right gauge shows what I do with the connected vacuum pump, the oscilloscope shows the output voltage of the sensor in real time (sry for bad camera positioning and no explanations, it was recorded only for myself):
Youtube: Test Air pressure sensor / MAP Sensor

In the future I want to compare the 10$ AliExpress Mitsubishi Pajero Montero V88W V98W L200  Air Pressure Sensor to the Yamaha FZ 07 Sensor. I assume they could be identical.
I will connect them both to negative air pressure with an Y-piece and record both outputs with the oszi at the same time, then we will see

 

Edited September 18 by ElGonzales

[MafiZed]

On 7/26/2021 at 7:39 AM, ElGonzales said:

Not a good picture, but I think you can see the black bottom of the sensor where I put on the transparent hose. Left side of the bike, green arrow is pointing to it.

 

View from the other side, fuel tank is removed:

I've played around with some of these aftermarket sensors. I have ordered some cheap Chinese ones which are looking absolutely identical to the original Yamaha sensor. The specification and the behaviour should be the same but I never had a chance to compare them directly 

 

FYI, this is the output of such a MAP or air pressure sensor (how Yamaha calls it). Voltage in relation to connected negative air pressure. Right gauge shows what I do with the connected vacuum pump, the oscilloscope shows the output voltage of the sensor in real time (sry for bad camera positioning and no explanations, it was recorded only for myself):
 

In the future I want to compare the 10$ AliExpress Mitsubishi Pajero Montero V88W V98W L200  Air Pressure Sensor to the Yamaha FZ 07 Sensor. I assume they could be identical.
I will connect them both to negative air pressure with an Y-piece and record both outputs with the oszi at the same time, then we will see

 

I know it's been year's but that just means you've had plenty of time to do it lol hopefully you're still on here, did you manage to test out the aliexpress sensors?

[ElGonzales]

I tested out the aliexpress sensor on the workbench. The problem is, I still have to compare it with the original yamaha sensor. But everytime I had the plastic covers removed from my bike I forgot to do this, sorry
And now my wife rearranged the furnitures in my working room and I can't actually find the chinese sensor anymore

I still have the old diagram of it's voltage output in relation to the pressure:


The type was for Mitsubishi Pajero with the same number 1865A03 like this:
https://german.alibaba.com/product-detail/Air-Intake-Boost-Pressure-Map-Sensor-1600213309297.html

Now we still need the same diagramm for the Yamaha sensor to check if they give the same output voltage on a certain pressure
I will install steel braided brake lines and a new air filter in the coming cold months, I put this on my To-Do list.