Please help me solve this

JOSEPH LAMAR · May 4

I have a 2020 axis 500 and I have replaced the TPS twice and the whole throttle body assembly once and still have code 122. I can barely drive the thing. It bucks and surges like crazy

Savage3 · May 5

What is the voltage coming into the TPS?

Is fuel making it to the throttle body?

Is fuel making its way to the spark plug?

If so, how much?

Hollywood · May 5

Also may want to check valves as well as fuel pressure. Just replaced fuel filter on my 2014 700 now runs like new. Good luck!

JOSEPH LAMAR · May 6

Well I just got it back from a shop and they said it was the TPS and that I had to replace the whole throttle body. It runs fine it just bucks like hell at a certain rpm

Hollywood · May 6

Man, that doesn't seem right. Tps on eBay or Amazon is like 18 bucks. Can't imagine you're going to need a throttle body probably just a cleaning. Sounds like a shop trying to make a payday.

Savage3 · May 6

The definition of insanity is to continue doing the same thing and expect a different result.

You already performed the TPS replacement twice!

I agree, that diagnosis doesn't sound reasonable.

Is there information we haven't heard of this far?

Hate to see you spend more money and not correct the problem.

Look for low voltage input at the TPS. Must be a poor signal.....

Hollywood · May 6

Motor needs fuel compression and spark to run. Before you shoot the parts cannon eliminate what you have and don't have.

Dean Sokoll · May 6

Pull your speed limiter and see if it runs better. It’s next to the battery, the box says speed limiter on it. Unplug and take it for a spin. I changed a bunch of stuff on mine until I tried that. I believe it limits the speed in which the machine backs up.

JOSEPH LAMAR · May 6

I have tried pulling the speed limiter and I have good fuel pressure. I have changed spark plug and coil so no problems there. Do you happen to know which wires to check the input on the tps

Hollywood · May 6

Check for spark. Have seen bad NEW plugs as well as coils.

Savage3 · May 6

This is not the same equipment, but, will get you in the ballpark! You will have to research the specs for Axis.

The concept is the same, basically, the TPS is a potentiometer that is feeding information back to PCM that controls timing. ( In a nut shell)

Trying to keep it simple......

Use this link to grasp basic fundamentals, then study how tps works.....then perform test

Dean Sokoll · May 6

Sorry, I do not.

Greg Kilgore · May 6

Did you or shop reset the computer after changing parts?

Kinda simple.

Look here for a lot of good information on these and other engines.

https://chinariders.net/showthread.php?t=15675

Look at post #5

"Rebooting the ECU

Perform the following steps to reboot the ECU.

1. Turn off the ignition for 15 seconds.
2. Turn the ignition on/off for 5 cycles. Make sure each cycle lasts about ½ second, verifying the start of the fuel pump for each cycle. If the fuel pump doesn't start during any cycle, begin the entire reboot procedure from the beginning.
3. Turn off the ignition for 15 seconds.

__________________
Spud"

The Motorcycle Doctor has another procedure for resetting the ECU but I think the above procedure is safer.

Savage3 · May 6

Good idea! Worth a try for sure! No cost, no harm, no foul!

Greg Kilgore · May 6

Joseph,

A few questions.

1. What is the "certain" RPM?

2. What speed?

3 What range is the drive selector? Meaning "High", "Low", or "Reverse"?

4. Does it do it with drive selector in "Neutral"?

5. 2 or 4 wheel drive?

Have you tested/inspected the speed sending unit on the rear differential and gear oil? See pic.

Do NOT just try and remove the sensor. The wires will just twist and brake. There is a connection on the wires coming from the sensor about 5-7 inches from where is screws into the differential. Disconnect the wire and turn the sensor and wires as one unit.

JOSEPH LAMAR · May 6

It happens around 3100 rpm it does it in neutral and in drive. I've looked at the speed sensor already. It's 4wd

JOSEPH LAMAR · May 6

And I reset computer with a scanner

Greg Kilgore · May 6

What scanner? Model number.

Did you have to buy or make an adapter cable.

There are just a few scanners that can read and reset the computer. The ECU should be a Delphi MT05. Try the procedure above. It's free, easy, at at least you can say "I told you it wouldn't work."

So at 3100RPM in neutral and in Hi range (2-wheel or 4-wheel) and Lo range (2-wheel or 4-wheel) it will surges.

If it does it in neutral, then it shouldn't be anything speed related. It would should be something with a sensor that controls the RPM to keep excessive from hurting the engine.

Will it go above the 3100 RPM? Or cutting out at 3100 like it's hitting a Rev Limiter?

JOSEPH LAMAR · May 6

Ts-301 is the scanner no adapter needed. It will go above 3100 that's just when it starts to surge. And I have tried every method to reset the computer. I think I'll have to find a better shop to look at it