help please Im a mechanical numpty
Discussion
Ive recently had car fully serviced but it came back ticking over at 1500rpm which seems too high.Ive just come out of hospital and cant drive so cant take it to be altered. Im sat on my a--e doing nothing and want to alter the tickover and then start fitting my new induction pipes. As the title says I am a mechanical numpty but I wouldnt mind having a go so any help would be appreciated.
Thanks in advance Aub
Thanks in advance Aub
Post a service it can be the adaptives and it needs to be driven to get it to settle.
Sometimes post service problems surface eg t-pots.
Are you fitting short induction - do you intend to fit a different ecu chip? I would attend to the current probs before fitting a chip or induction.
But you already know that!
Sometimes post service problems surface eg t-pots.
Are you fitting short induction - do you intend to fit a different ecu chip? I would attend to the current probs before fitting a chip or induction.
But you already know that!
Yes I have tried ringing the people who serviced the car but I got the impression it wasnt worth worrying about.The last time I drove the car it was working well other than the tickover being high. I was hoping it just needed adjusting and I could do it myself but I dont know how to. As for the induction kit it does come with a new chip which I will fit when the pipes are fitted.Is there some adjustment for tickover or is it all done through the ECU.
Thanks for the replies Aub
Thanks for the replies Aub
Gazzab said:
There is no idle screw.
Yes there is, it's at the back of the throttle bodies by where the cable attaches to them. In typically TVR fashion it's not exactly a paragon of precision engineering, however you could try winding it back a turn and seeing what difference it makes.HiYa,
Assuming (if you're as big a numpty as me) that you haven't got a clue how to connect the PC up then this'll give you summat to do.......
1> Remove the cover which crosses the back of the engine bay and covers the battery on the nearside and the brake reservoir on the offide (I think it is one 4mm countersunk Allen screw at the front on each side) You may have to pull the windscreen washer feed tubes though if yours has no play in this area ( I bought some longer tubes as this cover has to come off every time I go under the bonnet
)
2> Remove the driver's side airbox (On mine it is attached by three 4mm allen bolts, to the two mounting brackets fore and aft of the valve cover - and there are two breather pipes which push-fit onto the lower side)
3> On the photo below you will see where the throttle cable comes through from the clutch and brake reservoir cubbyhole. The throttle cable is held onto its anchor plate by two nuts which adjust the length of the inner cable relative to the outer cable guard. If these have been miss-tightened then you might have the inner cable pulling too much on the throttle assembly.
4> Once you've taken the airbox off and slackened slightly (so they can be adjusted by hand) the adjusting nuts - Start the engine and adjust the nuts so that the outer cable is effectively slackened.
Hopefully this will lower the tickover rate.
5> Tighten the nuts to the required rev level and replace airbox (Don't forget to attach the two drain/bleed pipes to the bottom of the airbox on refitting). Refit the back cover being careful to trace the paths of the windscreen washer tubes.
Close-up of cable adjusters on bracket.
Assuming (if you're as big a numpty as me) that you haven't got a clue how to connect the PC up then this'll give you summat to do.......
1> Remove the cover which crosses the back of the engine bay and covers the battery on the nearside and the brake reservoir on the offide (I think it is one 4mm countersunk Allen screw at the front on each side) You may have to pull the windscreen washer feed tubes though if yours has no play in this area ( I bought some longer tubes as this cover has to come off every time I go under the bonnet
)2> Remove the driver's side airbox (On mine it is attached by three 4mm allen bolts, to the two mounting brackets fore and aft of the valve cover - and there are two breather pipes which push-fit onto the lower side)
3> On the photo below you will see where the throttle cable comes through from the clutch and brake reservoir cubbyhole. The throttle cable is held onto its anchor plate by two nuts which adjust the length of the inner cable relative to the outer cable guard. If these have been miss-tightened then you might have the inner cable pulling too much on the throttle assembly.
4> Once you've taken the airbox off and slackened slightly (so they can be adjusted by hand) the adjusting nuts - Start the engine and adjust the nuts so that the outer cable is effectively slackened.
Hopefully this will lower the tickover rate.
5> Tighten the nuts to the required rev level and replace airbox (Don't forget to attach the two drain/bleed pipes to the bottom of the airbox on refitting). Refit the back cover being careful to trace the paths of the windscreen washer tubes.
Close-up of cable adjusters on bracket.
Edited by Mr Cerbera on Thursday 10th February 18:03
although i know about having to see what the throttle pot values are using a computer, which is how the ECU is seeing these values as a voltage, its it possible to disconnect the wires to the pot to get a resistance reading using a multi meter, or is this how they are set up.
When i adjust potentiometers at work on rail machinery you are able to balance the pot up by reading the resistance by twisting it on its mount and getting an even reading on both sides of the positive and negative taking a reading from the the cable terminals, is this similar to setting up these pots.
I take it the adaptive's are a limited adjustment of the voltage that the ECU is able to send to the pot itself before more mechanical or repositioning of the pot is needed?
As an engineer i'm still learning every day of my job which i have been doing ten years plus my apprenticeship and find applying similar things between cars and machines i am able to understand both better as they are the same in principle but different in application.
Peter
When i adjust potentiometers at work on rail machinery you are able to balance the pot up by reading the resistance by twisting it on its mount and getting an even reading on both sides of the positive and negative taking a reading from the the cable terminals, is this similar to setting up these pots.
I take it the adaptive's are a limited adjustment of the voltage that the ECU is able to send to the pot itself before more mechanical or repositioning of the pot is needed?
As an engineer i'm still learning every day of my job which i have been doing ten years plus my apprenticeship and find applying similar things between cars and machines i am able to understand both better as they are the same in principle but different in application.
Peter
pmessling said:
although i know about having to see what the throttle pot values are using a computer, which is how the ECU is seeing these values as a voltage, its it possible to disconnect the wires to the pot to get a resistance reading using a multi meter, or is this how they are set up.
When i adjust potentiometers at work on rail machinery you are able to balance the pot up by reading the resistance by twisting it on its mount and getting an even reading on both sides of the positive and negative taking a reading from the the cable terminals, is this similar to setting up these pots.
I take it the adaptive's are a limited adjustment of the voltage that the ECU is able to send to the pot itself before more mechanical or repositioning of the pot is needed?
As an engineer i'm still learning every day of my job which i have been doing ten years plus my apprenticeship and find applying similar things between cars and machines i am able to understand both better as they are the same in principle but different in application.
Peter
Hi Peter,When i adjust potentiometers at work on rail machinery you are able to balance the pot up by reading the resistance by twisting it on its mount and getting an even reading on both sides of the positive and negative taking a reading from the the cable terminals, is this similar to setting up these pots.
I take it the adaptive's are a limited adjustment of the voltage that the ECU is able to send to the pot itself before more mechanical or repositioning of the pot is needed?
As an engineer i'm still learning every day of my job which i have been doing ten years plus my apprenticeship and find applying similar things between cars and machines i am able to understand both better as they are the same in principle but different in application.
Peter
Without the software you may well get the throttles reading exactly the same but that's not the most important part of the puzzle.
The trick is to get both throttles either trimming or adding together through the rev range, which you can see by how far the adaptives are changing.
It is a very sensitive job and getting it 'spot on' can be time consuming.
OP,
First port of call has to be whoever serviced your car, 1500rpm idle is WAY to high and IS something to worry them about!
Duncan
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