False flow readings from flow sensor.

[Richard L]

Originally Posted by yokimazoku

This is probably true. I think i was on the edge of how close i could be bc if i move it over about and inch it picks of the false flow again even when wrapped. I did notice with the hfs 4 that i dont get a set flow on the gauge its always moving. Only time its constant is if i have the car off and in ACC and set the controller to SYS to make it spray. Then it stays at a constant 6 bars. But as soon as i start the car i get an extra 2 or 3 bars bouncing around. I assume thats normal yes? I Even moved the sensor out of the engine bar for testing same results.

Unplug the clip from the sensor body. I if you still get readings, the pulse must come from somewhere else. If reading appears again after re-clipping, the signal ahas to come from the sensor itrself.

[skeurton]

Last night, I did a few things....

-Added a second nozzle to be able to inject 100% meth.

-Set the P/I-R trim to full IDC.

-Removed the flowsensor turbine and tried cleaning it again. Didn't completely disassemble it, but ran more compressed air through it.

-Took a piece of wire loom and covered it with several layers of electrical tape. I then placed the whole loom over the flowsensor turbine in hopes that it would shield both the flow sensor and turbine.

Once everything was back together and buttoned up, I started the car and the bars on the gauge were going crazy just sitting at idle while waiting for it to warm up. Took it out for a spin, got on the throttle, and the system was spraying fine. The gauge still continued to show false flow after that. I didn't feel like messing with it anymore, so I left it alone and went to bed.

Started my car this morning to go to work and everything seemed ok. No bars showing as I let it idle. Left my house and everything still looked good. Once I was on the highway, I opened up on the throttle, system sprayed fine, let off the gas, and the gauge started showing false flow again.

8 and a half hours later, I left work. Started the car, everything looked fine again. Got on the highway, got on the gas, system sprayed fine. When I let off, I was expecting the gauge to go crazy again with false flow. TO MY SURPRISE, IT DIDN'T!!! I tried it a good 5 or 6 times on the way home and everything worked perfectly! I was also able to trigger and set the WL and WH failsafes. I even caught a datalog of when the failsafe tripped in high boost. It worked flawlessly.

Now I can finally get to tuning this thing!

[Richard L]

Weird...

Did you switch something off between the two periods? ac fans, cold start etc?

[skeurton]

Originally Posted by Richard L

Weird...

Did you switch something off between the two periods? ac fans, cold start etc?

It is weird, but I did nothing different.

[Richard L]

Please keep an eye on it and post.

[hotshot25120]

I have false reading too in my car

here a picture of where my sensor is located :

[Richard L]

Can you unclip the sensor at the FAV and tell me if the false flow reading is still there.

[dave80]

hotshot I had the fav assembly in the same location (mkv gti) and no matter what I did the false readings wouldn't go away. I moved it all the way to the left (looking at your pic) next to the coolant overflow tank and that solved my problems.

[Richard L]

Do we have a definitive culprit that caused it?

The question still remains:
1) Interference from neighbour noisy cables
2) The sensor turbine is cavitating between the magnetic poles due to vibrations.

[hotshot25120]

Originally Posted by dave80

hotshot I had the fav assembly in the same location (mkv gti) and no matter what I did the false readings wouldn't go away. I moved it all the way to the left (looking at your pic) next to the coolant overflow tank and that solved my problems.

Thanks I will try that.