4.5 Throttle Pots renewal
Discussion
Good evening everyone. Appreciate perhaps wrong time to ask ahead of the THE game ….. but then again no rush…
Have a 4.5 that has of lately developed a stutter between 1500- 2500 and does not seem to run right. Hesitates but then takes of when asked. Had coils replaced end of last year and all HT Leads and spark plugs 50 miles ago. Had throttle pots cleaned and adaptives and pots properly reset. Was advised that there is a chatter from the drivers side one but ECU compensates correctly. Car ran right for a good few miles but the fault has then returned. Mechanically idle is correctly set at 950 and she holds this and idles smooth enough. Now I have rs ajp app on the phone and can see the values the ecu gives. I assume the fault is throttle pot related ? Reset adaptives and runs fine after that but then relearns the ,fault,. Now I do have two new blue throttle pots and mechanically minded and able can replace them myself. As the car was running right with the current throttle pot values will it be okay to put a new one on the drivers side and adjust the values to the same as before ? The drivers side is the one that moves around - passenger side odd bank? Is rock solid at 18 when idling. Since I don’t change anything mechanically I hope that’s the right way forward ? Any help would be appreciated here as currently the car is not a pleasure to drive.
Many thanks in advance !
Ulrich
Have a 4.5 that has of lately developed a stutter between 1500- 2500 and does not seem to run right. Hesitates but then takes of when asked. Had coils replaced end of last year and all HT Leads and spark plugs 50 miles ago. Had throttle pots cleaned and adaptives and pots properly reset. Was advised that there is a chatter from the drivers side one but ECU compensates correctly. Car ran right for a good few miles but the fault has then returned. Mechanically idle is correctly set at 950 and she holds this and idles smooth enough. Now I have rs ajp app on the phone and can see the values the ecu gives. I assume the fault is throttle pot related ? Reset adaptives and runs fine after that but then relearns the ,fault,. Now I do have two new blue throttle pots and mechanically minded and able can replace them myself. As the car was running right with the current throttle pot values will it be okay to put a new one on the drivers side and adjust the values to the same as before ? The drivers side is the one that moves around - passenger side odd bank? Is rock solid at 18 when idling. Since I don’t change anything mechanically I hope that’s the right way forward ? Any help would be appreciated here as currently the car is not a pleasure to drive.
Many thanks in advance !
Ulrich
Does it stutter on a steady throttle at anywhere between 1500-2500RPM, or it is if you accelerate from 1500RPM up to 2500? It could be a noisy throttle pot causing the ECU to falsely trigger acceration enrichment when you're at a steady RPM, or you could have fuel mixture issues. The original TVR software has a readout of whether the ECU has triggered acceleration enrichment. What does RS AJP say the lambda sensors are doing? They should flick from low to high voltage at steady RPM, if you're accelerating they'll be pegged either low or high, can't remember which voltage refers to a rich condition.
Hello Will,
many thanks for your reply here. Basically feel it most when you ease along at light throttle - say 40 in 4th or third - floor it and no probs- equally over 4 k when Lambdas cut out. The Lambdas are also switching happily back and forth - both. One of them is new - the other was replaced about 3 years and 10000 miles ago. I noted that the adaptive values on the even bank (drivers side i.e. TP 1) flick wildly along between -30 - 0 and above. The odd bank is around 0-10. When I changed the spark plugs I noted that the odd bank ones were a bit sooty black (no oil though - phew) whereas the ones from the even bank were light brown / greyish.
After I had reset the adaptives car was running nice and pulling like a train but has since relearned the bad habit .....
When she runs and I unplug either throttle pot car continues to run and doesn't die.
IF I change the even TP to a good one i.e. a brand new one and dial it in the same as was set up before and reset adaptives
should have not got to go through a full set up a I assume. The throttle linkage is nice and tight and she had been set up mechanically for 950 idle which she holds steadish - flicks a few up and down but nothing wildy.
Ulrich
many thanks for your reply here. Basically feel it most when you ease along at light throttle - say 40 in 4th or third - floor it and no probs- equally over 4 k when Lambdas cut out. The Lambdas are also switching happily back and forth - both. One of them is new - the other was replaced about 3 years and 10000 miles ago. I noted that the adaptive values on the even bank (drivers side i.e. TP 1) flick wildly along between -30 - 0 and above. The odd bank is around 0-10. When I changed the spark plugs I noted that the odd bank ones were a bit sooty black (no oil though - phew) whereas the ones from the even bank were light brown / greyish.
After I had reset the adaptives car was running nice and pulling like a train but has since relearned the bad habit .....
When she runs and I unplug either throttle pot car continues to run and doesn't die.
IF I change the even TP to a good one i.e. a brand new one and dial it in the same as was set up before and reset adaptives
should have not got to go through a full set up a I assume. The throttle linkage is nice and tight and she had been set up mechanically for 950 idle which she holds steadish - flicks a few up and down but nothing wildy.
Ulrich
Ulrich said:
This afternoon both TP's replaced against two new new ones - set at 19 as idle - give and take 1 and hey presto night and day - runs miles better - and very smooth - picks up easy and no shunting and stuttering anymore...Adaptivs on idle sit nailed on 0.
Shows the value of new throttle pots, and yet they have been NLA from the official suppliers for several yearsYou can use the white ones but as they are counter clockwise (correct me here If I have it the wrong way round..) you need to drill through the white plastic bit and put them on the other way round and connection end down plus I think the outer connections in the plug must be switched around. The aircon compressor can get in the way but this is the bodge around the problem. I was simply lucky to find some new blue ones.
don't know if these are for you 4.5s out there https://spareto.com/products/mobiletron-sensor-thr...
sorry don't think they are available
sorry don't think they are available
Edited by jong1e on Sunday 18th July 13:24
Byker28i said:
TwinKam said:
I believe that Joolz at Kits & Classics (spitfire4v8 on here) has stock of both blue and white ones.
This - Use Joolz, he did a bulk buy to provide for ownersImran999 said:
I thought I had read that the last group buy resulted in the supplier shipping a quantity that was an order of magnitude higher than had been ordered. He should be swimming in them!
IIRC, he ordered Blue, but got White. So had to reorder Blue, and got Blue. But they may have mostly been pre-assigned...
Ha yes, there was a slight mess-up on the initial order, how i laughed at the 2 grand outlay, hahaha 
then how I laughed even more at shelling out another 2 grand to get the correct ones .. hahaha
The good news is that the black (not blue, you can't get blue ones at all) pots have all but sold out so I will be placing another order soon.
The other good news is that I use the white ones for my RoverV8 throttle pot upgrade, so not all was lost, phew!
then how I laughed even more at shelling out another 2 grand to get the correct ones .. hahaha The good news is that the black (not blue, you can't get blue ones at all) pots have all but sold out so I will be placing another order soon.
The other good news is that I use the white ones for my RoverV8 throttle pot upgrade, so not all was lost, phew!
spitfire4v8 said:
Ha yes, there was a slight mess-up on the initial order, how i laughed at the 2 grand outlay, hahaha then how I laughed even more at shelling out another 2 grand to get the correct ones .. hahaha
The good news is that the black (not blue, you can't get blue ones at all) pots have all but sold out so I will be placing another order soon.
The other good news is that I use the white ones for my RoverV8 throttle pot upgrade, so not all was lost, phew!
Bless you Jools, glad it all worked out for you in the end then how I laughed even more at shelling out another 2 grand to get the correct ones .. hahaha The good news is that the black (not blue, you can't get blue ones at all) pots have all but sold out so I will be placing another order soon.
The other good news is that I use the white ones for my RoverV8 throttle pot upgrade, so not all was lost, phew!
steviejasp said:
gruffalo said:
I have a couple of blue ones spare.
PM me if you need some.
The over supply to Jules was I seem to remember of white ones.
Hi, I’ll take them if they are still available please.PM me if you need some.
The over supply to Jules was I seem to remember of white ones.
Call me on 07920 494667.
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