Suzuki DF60 2004 Won't go above 3000 rpms No error codes

[go2ski]

The white wire reads 1.7-1.8 volts with the hose disconnected I tested that again in gear in idle and off it reads the same. I took a recording with my phone of the sds due to my software having problems and I uploaded it here. I want to be sure the MAP sensor is failing because it isn't cheap.

(If the link isn't working go to the other videos from the previous replies it will be on the same channel most recent upload)

[go2ski]

[go2ski]

Could you also tell me what the volts on the white wire are supposed to be.

[redlowrey]

mate listen carefully only do what I ask you to do, with your meter connected to the white signal wire with the key on engine off what have you got.
At sea level it should be 4 volts what is it.

With the hose disconnected as soon as it starts and the computer does not see a changing voltage it will bring on the check engine light and substitute a value for it.
This is why I said to you if you see 4 volts on the signal wire with the key on engine off as soon as the engine starts go to wide open throttle.
Just tell me what voltage you have with the key on engine off and we will go from there.

[go2ski]

The voltage is all 1.7-1.8 on key on engine off and ldle and full throttle on the white wire I did test that.

[redlowrey]

Ok it looks like the sensor has failed just do one more test, connect your multimeter ground to the battery negative and probe the black and white wire, sensor ground with the key on, you should not see more than 40 mv on it.

I have equipment to test the sensor on the engine or on the work bench and it’s hard over the internet trying to show someone how something works and how to test and be confident that the tests are right.

When I test a map sensor on the engine I will check supply voltage 5 volts, sensor ground, no more than 40 mv, signal voltage using a vacuum pump which will vary between 4 volts no vacuum, to 1 volt high gauge vacuum, and I will tap on the sensor to see if there is any changes to the readings.

[redlowrey]

You are checking these voltages with the map sensor wiring plug connected aren’t you, it just dawned on me, because I see changes on your sds, you say no changes at all.

[go2ski]

The map sensor is connected to the engine the only thing that’s not connected is the hose to the map sensor.

[redlowrey]

Very good I was thinking that you had the sensor unplugged, because the computer will send a bias voltage down that wire around 1.5 volts with the sensor unplugged key on.

[redlowrey]

I just had a thought, if the white signal wire was broken where it enters the map sensor you will only see the bias voltage, just unplug the the connector and test the voltage on the pin it should be the same with the key on.

[redlowrey]

You are using a digital multimeter when you are doing these checks aren’t you, because if you are using an old analog meter with a moving needle, the meter will consume more current than the circuit you are testing pulling the voltage low.

Something just does not add up, you have a voltage that has 1.7 volts on it that should have 4 volts on it, key on engine off, the voltage won’t change which should have switched the check engine light on and I have seen the manifold vacuum changing on the sds you put up first.

[go2ski]

I am using a craftsman digital mutlimeter the red wire is 4.98v the black wire is 1.8 on the 200mv DC mode and the white wire is 1.83v. The hose is unplugged when I’m testing this.

[redlowrey]

Progress, there should be zero volts on the ground black,

[go2ski]

So the sensor is not working for sure?

[redlowrey]

That’s right, that ground wire should have zero volts or no more than 40 mv just to make you feel good I tested a map sensor on a df 140, key on engine off red wire 5volts white wire 4 volts black and white ground zero volts.

Map sensor disconnected key on red wire 5 volts white wire 1.4 volts ground zero volts.
You have a bad sensor ground, follow the black and white wire it will go to a terminal block with other black and white wires then to the computer.

I knew that there was some other problem if you had of replaced the map sensor you still would have had the same problem.