How long does a TPS last?

[anthonym]

reading this:

https://jalopnik.com/how-electronic-throttle-control-works-499966101

methinks my Throttle Position Sensor is one of the graphite type; question is how long is a long time for one of these. 

I imagine miles rather than years will be the measure.

Mine's done 52,000 miles.

Anthony

[aerobod - near CYYC]

I’m on my 4th in 30,000km on my R400D, vibration seems to be the killer. Tried a cheap CAD$10 eBay one for the 3rd that lasted 500km, back to the CAD$90 Ford part for the 4th that has lasted about 5,000km so far. May go for a Penny and Giles Hall effect contactless one next.

[rj]

I'm on my firstn in  my K, 25kkm

[SM25T]

I dont think I have changed mine yet .... 96k

[rj]

By the sound of it Rover was better quality than Ford is :-p
 

[anthonym]

ok, so that's a wide range. I am interested to see inside one if anyone can take one to bits; specifically the graphite track and signs of wear, how it wears. Because while adjusting mine I could swear I could feel a sort of lump or groove causing resistance and getting it to stay in place on exactly 0.45 ohms is impossible so far, it keeps wandering off by 0.01 plus or minus.

Anyone have a linky to a hall effect version? that works on my K.

[rj]

Jenvey does one. But... you'll need to adjust your map to work with it.

0.45 ohms is pretty much a short circuit. Are you sure it's not kilo-ohms?

If it's a 5k pot then it means 1 volt per kohms - and output as a consequense 0.45 to 0.46 volts.

[CharlesElliott]

When our race series brought in a class with the aluminium VVC intake, we started having TPS failures regularly. It was improved with a more flexible wiring sub-loom and a thin rubber gasket between the TPS and the plenum. Vibration was the killer as you suggest.

[Markiebabes]

,45 volts not ohms Anthony

Penny and Giles-    https://www.cw-industrialgroup.com/Applications/Motorsport/Rotary-Position-Sensors/NRH300DP-No-Contact,-Rotary-Position-Sensor

they are left or right hand version cant remember which for the roller barrels  

HTH 

 

 

[7 wonders of the world]

Emerald is easy, just follow the Throttle pot set up link, it take seconds  

[anthonym]

7w - yes did that this day.

howdy markiebabes been a while. :-)

 

 

p.s. I've ordered a new TPS, I think 20 years is long enough.  From Redline of course.

[Shaun_E]

I had 2 failures on my K and eventually switched to a P&G Hall effect one which has been on the car ever since through sprints/hiilclimbs, circuit racing and track days. You should really re-map the car as, although the throttle pot range can be reset, you don't know what the behaviour is in between full open and full closed - the "curve" may be different to the original TPS.

[rj]

Have been thinking a little:

Both sensors - mechanical or solid state - should be lineaer. This should in theory mean that if you do the calibration as mentioned by Anthony elsewhere all should be good.

If you have another ECU make sure your "end points" have been set up correctly to ensure that the load sites are detected as wished. If I were to replace mine (MBE 967) I'd start measuring output from TPS (in volts) at idle and at WOT (IGN on, but engine NOT running) and then repace the sender to check if the outut are the same.

If not I'd make a spreadsheet to correct the values where I calculate the offset and span for both sensors and of course correct the values in the map.

I think that's what the calibration feature of the Emerald does, but with the MBE you are able to create more load sites at low opening angle which makes you able to create a more accurate map for part throttle. I have very little knowledge to the Emerald, but I don't think you can map the TPS this way on it.

[revilla]

Not directly relevant in your case, but for those with "proper" ECUs (standard Rover MEMS) and a "proper" intake system (not those funny rows of trumpet things you funny people seem to like)  ...

Standard MEMS3 uses MAP for load information and the only things it actually uses the TPS for are:

1. Detecting closed throttle, so it knows when to manage the idle speed.
2. Detecting rapid throttle movements, so it knows when to enrich to enhance the throttle response.

(Information direct from the horse's mouth)

When you do the calibration procedure (ignition on, throttle fully open and fully closed five times, ignition off) it trains the ECU to recognise the voltage corresponding the closed throttle, but it doesn't do anything about the scaling or WOT value. If you look after calibration on OBDII, closed throttle should give a calibrated TPS value of 3.92% (1/255th - it's digitised in 8 bits) but WOT will vary from one TPS to another, it's just whatever you get.

(Information from my own investigations)

In this case, replacing the TPS with a non-contact one should be very straightforward. So long as it gives a fairly consistent voltage at closed throttle (if it didn't it would be useless anyway) and something even vaguely linear to tell the ECU when it's moving quickly it should just work after calibration.

(He says ... in theory ... never having actually tried it!)

[anthonym]

Dup

[anthonym]

‘Morning rj

bit slow on the uptake here. So 1V per kohms means my .46 is .46 of a volt ant .88 is .88 of a volt..?

I am revisiting this thread because replacing the injectors and lamda sensor leaves just the TPS wear question. As I understand it these do wear because they have a track inside that the connection rides along back and forth. So if you spend all your time on motorways it won’t experience such frequency of movement as only ever doing twisties. Track use.. always full throttle or none? Slightly tongue in cheek with this analysis, though it is tempting to thing different use types will affect wear, but I grant it may just affect where it wears and not the absolute total of wear.

point is whether to fit the new TPS I have waiting in the wings or whether yet again there is a risk of that affecting the maps. I hear loudly the voices that say resetting the Emerald K6 will align the maps, but Steve G asked me to return the TPS to the same setting as it was, which intuitively ( sometimes not reliable in these matters) seems to contradict.

Anyway, the sleuthing process continues though not so apparent in here as it involves doings rather than chattings.

28. c here, max is usually 25 (@1300m) what’s it like down there at sea level?

Regards

Anthony

and for part numbers and identification in the future: seems the pic is above.

also discovered that the TPS has a return spring in it, so twiddle it left and it springs back right quite strongly (viewed from the rear and off the car) wonder if that weakens over 20 years, it must. Does it matter.. I guess not. 

 

[rj]

It denends on how the load sites are defined by the Emerald, and I can't answer for certain.

I /think/ it simply divides the difference from Vmin to Vmax into 16 load sites as in load site 1=Vmin, Load site 2=Vmin+(1/15x(Vmax-Vmin)), Load site 3=(2/15x(Vmax-Vmin)).... to Load site 16=Vmax

If this is the case you can freely swap TPS and re-calibrate the ECU. You also need to make sure the ariflow at idle is as it's supposed to.

If, however, it's done like in the MBE it's crucial to set the TPS to the voltage at the pre-defined value and set the ariflow to the corresponding flow. The MBE is non-linear. You can define each load site to be the voltage you want. This enables you to have many load sites at part throttle - especially at low opening a small difference in opening angle will make a huge impact on airflow. Hence you can make you part throttle drivability much better.

Not much help, I know...

[anthonym]

Deleted to new thread