CAT 299C Loosing travel speed

[JRRod]

Cat 299c 950hrs # JSPO2170
Hello, Having issues with my machine. If im moving a load from A-B it will loose speed just slows down gradually, Norm or rabbit mode. If i back joystick back to center ( stop) & go back into it it will hold till I move joystick again to turn etc. Same if i have to use rabbit mode i will need to stop machine start going forward then hit rabbit it seems to have good take off speed then will slow down ( random distances ) when I need change in any direction ...Everything else seems to work fine boom/bucket etc .... Any help of anyone out there maybe has same issues or can help would be very appreciated! Thank you !

Things that ive checked so far :
1- Speed sensor wires around pumps seem to look ok no obvious damage to wires
2- Changed hydrylic filter again ( just changed hydro fluid 50hrs ago)

3- poured old hydro fluid out old filter in clear container looking for any metal or brass particles ( found Nothing was clean)

4- Had a tech come out check for codes ( (no codes) did check PSI 42 .. he could not check flow tho ... & Joystick was communicating seemed to be ok

5 - Machine is pretty well maintained oils filter etc

 

[hOOPSNAKE]

I have this exact problem on a new to me machine. Hopefully someone has some idea.

 

[Tyler d4c]

Throttle position sensor on the pedal need a new one and it recalibrate or just calibrated i had the same trouble on a 279c

 

[Chrisso]

Throttle position sensor on the pedal need a new one and it recalibrate or just calibrated i had the same trouble on a 279c

x2
Was the tech a dealer Tech? If not I don't think he would've seen the special instruction for this...

The TPS updates from 160-2443 to 266-1467. Special instruction calls for calibrating it first. If it fails, replace with new p/n and try again. Honestly, if your paying for a tech to come out and calibrate, and this fixes the problem, I'd still replace it with the updated p/n.

Keep in mind this is still only one possibility... there's at least half a dozen things that could cause the same issue though.

 

[Tyler d4c]

x2
Was the tech a dealer Tech? If not I don't think he would've seen the special instruction for this...

The TPS updates from 160-2443 to 266-1467. Special instruction calls for calibrating it first. If it fails, replace with new p/n and try again. Honestly, if your paying for a tech to come out and calibrate, and this fixes the problem, I'd still replace it with the updated p/n.

Keep in mind this is still only one possibility... there's at least half a dozen things that could cause the same issue though.

The tech was me I have et and what not.

 

[Chrisso]

Ok great, even better. Let us know how you go with the calibration then, keen to know if it fixes.

 

[Tyler d4c]

Ok great, even better. Let us know how you go with the calibration then, keen to know if it fixes.

It fixed mine that was a year ago.

 

[hOOPSNAKE]

Dragging up an old thread, but….

I’m trying to calibrate the TPS.

I had to replace the throttle cable as the old one was worn and would not hold the same position once adjusted.
New cable is in and adjusted to low idle speed (1050 rpm) and high rpm of 2750.
My problem is, when the cable is adjusted to this range the incab diagnosis screen says the TPS percentage is 30% but et says it’s 45%. When I play with the cable adjustment and reduce the machine TPS to 20 or even as low as 5%, ET still thinks it’s 40 or 35%.
Unless I adjust the cable to be lower the first stage of the calibration fails and states it’s out of range-too high.
after I have adjusted the machines cable and brought the ET TPS reading down to >30% the calibration can start but fails on the last stage and complains the TPS is too high (out of range) but ET thinks it’s lower than the machine says on the diag screen.

I have a few pics of the problem. Hopefully someone has come across this problem.

 

[Chrisso]

I don't think you should be using the cable to adjust high/low idle. Should be screws on the governor that control this. Need your s/n to check any specs.

Have you changed any parts other than the cable?

 

[hOOPSNAKE]

I don't think you should be using the cable to adjust high/low idle. Should be screws on the governor that control this. Need your s/n to check any specs.

Have you changed any parts other than the cable?

No.

I haven’t touched the governor. I’ve been adjusting the length of the cable with the yokes at each end. This is how I’m getting the TPS to change its reading.

ET does talk about correct throttle cable adjustment but I can’t find that info in the workshop manual I have.

SN: JSP02180

 

[Chrisso]

Throttle cable adjustment is fairly straight forward... just need to make sure your cable adjustment is allowing contact on the high/low idle set screws at the governor, that's it. There's adjustments on the governor control lever and the foot pedal to adjust if needed to obtain this also. Your low/high idle specs are good whether it's adjusted properly not... it should still calibrate.

You said initially you had the same problem as the OP, did you have the same symptom coming to a stop unexpectedly? If so, I'd be checking the TPS p/n with the one I mentioned in post #4. Who knows, this could be the very reason the p/n has updated?

 

[hOOPSNAKE]

Throttle cable adjustment is fairly straight forward... just need to make sure your cable adjustment is allowing contact on the high/low idle set screws at the governor, that's it. There's adjustments on the governor control lever and the foot pedal to adjust if needed to obtain this also. Your low/high idle specs are good whether it's adjusted properly not... it should still calibrate.

You said initially you had the same problem as the OP, did you have the same symptom coming to a stop unexpectedly? If so, I'd be checking the TPS p/n with the one I mentioned in post #4. Who knows, this could be the very reason the p/n has updated?

Yes, I have the exact same problem.

This is the procedure I used to set the throttle cable.

It is for testing the Hydrostatic system. It’s the only mention on how to set the throttle cable.

 

[Chrisso]

Yep that's the one.

 

[hOOPSNAKE]

Why would the machine an ET display different TPS readings?

 

[Chrisso]

Can't really explain that one but...

Who knows, this could be the very reason the p/n has updated?

If you're machine was having the same symptom as the OP, ie slowing down to a stop whilst travelling, we need to check the TPS.

 

[hOOPSNAKE]

Can't really explain that one but...



If you're machine was having the same symptom as the OP, ie slowing down to a stop whilst travelling, we need to check the TPS.

Even though it’s not throwing codes, would this be a good procedure for checking the TPS? I can’t afford to just buy the updated one only to find it isn’t the problem.

 

[Chrisso]

It's a good place to start, but I think you've already found the problem in step 4, E.

 

[hOOPSNAKE]

Part number was new one. I rechecked the throttle cable adjustment and with a bit of back and forth from engine bay to throttle pedal, I got it all set.
Thankfully, it calibrated and the problem is solved.

Thanks for your help