450j throttle issue

I have a new to me 450j dozer. It has an intermittent issue. If you start the dozer it will idle and run full throttle perfectly. If you rev the machine to say 1200rpm it will surge roughly 300rpm. It’s not a huge deal and hasn’t caused any issues I just noticed it. I did just pull it in and done a full service including fuel filters. I have noticed that the throttle knob will allow you to go passed full throttle, but when you do it throws a light on the dash and returns to idle. You can return the knob to idle and cycle the key and everything functions as normal. I did not pull the codes from the dash yet. Has anyone ever experienced this? I have googled but haven’t had luck finding anything exactly like it.

Please post the machine serial number.

Did the surge start after the filter change?

T0450JX148104 is the Vin and it was doing it before the filter change

Was the seal that is between the filter bowl and the water separator filter in place?

Do you know how to check codes in the monitor? Will need to know what is in there.

The throttle dial will need to be replaced, regardless.

mg2361 said:

Was the seal that is between the filter bowl and the water separator filter in place?

Do you know how to check codes in the monitor? Will need to know what is in there.

The throttle dial will need to be replaced, regardless.

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Sorry for the delay I had knee surgery. Is that the rear most filter beside the seat? I made sure the filter had the needed seals when I replaced I didn’t see anything out of the ordinary. It doesn’t have any active codes. But under stored codes it reads as follows
SDM 1713.31
SDM 3359.31
SDM 1638.16
SDM 1638.0
ECU 91.9
SDM 1713.31

I believe that ECU code you have there is a A00 91 09 3: Throttle input not valid or not received.

001713.31 - Hydraulic Oil Filter Restricted
003359.31 - Trans Oil Filter Restricted
001638.00 - Hydraulic Oil High Temp
001638.16 - Hydraulic Oil High Temp Moderate
000091.09 - CAN Throttle Missing from TCU

Acecadet said:

001713.31 - Hydraulic Oil Filter Restricted
003359.31 - Trans Oil Filter Restricted
001638.00 - Hydraulic Oil High Temp
001638.16 - Hydraulic Oil High Temp Moderate
000091.09 - CAN Throttle Missing from TCU
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Thanks for the reply everything seems to check out. This only happens randomly when I over turn the knob it makes me cycle key. Would that not point to the throttle knob?

I would remove it and check it with an ohm meter throughout its entire sweep. If it glitches at all then replace it. I wouldn’t go replacing 170 dollar part without at least checking it first.

Acecadet said:

If it glitches at all then replace it.

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If you are using a digital meter, make sure it is set for manual ranging. if using auto-range (which it will be set to when first turned on), then it will give false glitches as it auto-ranges to the next scale.

Thank you guys!!