Throttle Sticking

[lovellracing]

Can anyone help?
The Throttle is sticking on my 3200gt It happened mildly a few weeks ago so I removed the throttle body and sent it back to Reman because it was under warranty. They said that they had found a problem with it. I stuck it back on the car and it seemed fine apart from a couple of times on starting there was no throttle response whatsoever, switching off and restarting seemed to do the trick. Now the throttle will not shut off from 35000 RPM. Can it be the pedometer or whatever its called (electronic throttle control) Give me a cable any day !!!

Cheers
Ray

 

[Contigo]

It's more than likely a sticking butterfly mechanism or the magnets are breaking down inside the TB itself. I'd send it back again! I'm on my 4th send back right now for exactly the same thing you describe so it i s an issue even when they have been upgraded to contactless.

 

[lovellracing]

Cheers Phil
I will call them tomorrow after all they do give a lifetime warranty
Ray

 

[davy83]

ok first of all the throttle on the 3200 is quite different to the 4200 so there is no common thread here.
I have a 3200 and so can comment on this a little. The throttle is like a lot of modern cars controlled by a pedal sensor, the engine ECU and an electronic throttle body which opens the throttle according to demand from the engine controller. it generally makes the engine easier to run.

The throttle sticking is most likely an issue with the throttle body on the front of the engine this is the most prone to issues. if you remove the air intake hoses you should be able to move the butterfly with your fingers (engine not running of course) if it is mechanically sticking this may be evident. The position sensors on the throttle body are notoriosly unreliable and i think the extreme temperature under the bonnet means they don't last long. These are often replaced with contact-less sensors which appears to help this problem and they last a bit longer. Maserati shed do these upgrades, as do a few others.

Also note that air leaks in the vacuum system and around the plenum cause problems with the electronic control system and can cause irregular engine speed. it might be worth checking for hoses around the plenum, and indeed listed for air noises under the plenum as there is a large cover which often comes loose and this can cause all sort of engine speed issues. Does it idle at 1000 rpm pretty steady or not?

While the pedal sensor can cause problems the throttle sticking open like that is not one of the symptoms i would associate with the pedal sensor. The pedal sensor was designed with a crazy intolerance to the difference between the two redundant outputs and also the output of the pedal sensor at idle, and so again the slightest problem with the pedal sensor makes it cause problems. Normally the car will throw an ECU light and log an error with either of these things failing so i am surprised you don't have errors? i make a replacement pedal sensor with contact less technology but i don't think that's what you need at this stage (yet ).

Can anyone help?
The Throttle is sticking on my 3200gt It happened mildly a few weeks ago so I removed the throttle body and sent it back to Reman because it was under warranty. They said that they had found a problem with it. I stuck it back on the car and it seemed fine apart from a couple of times on starting there was no throttle response whatsoever, switching off and restarting seemed to do the trick. Now the throttle will not shut off from 35000 RPM. Can it be the pedometer or whatever its called (electronic throttle control) Give me a cable any day !!!

Cheers
Ray

 

[highlander]

Apology for thread hijack but Davy, do you need the original pedal sensor to do your magic? Not needing one just now I think but as you say, only a matter of time and I do like to build up a store of essentials!

 

[davy83]

no its a complete replacement sensor, drop fit for the original, so no donor required! i looked at a refurb route but the Bosch things are all plastic and use cheap bearings its horrible, so the new one is all machined parts, precision bearings, solid metal, apart from the rotary encoder.

 

[highlander]

no its a complete replacement sensor, drop fit for the original, so no donor required! i looked at a refurb route but the Bosch things are all plastic and use cheap bearings its horrible, so the new one is all machined parts, precision bearings, solid metal, apart from the rotary encoder.

good man, put me down for one the next time you are doing a batch Davy.

 

[davy83]

i have one or two at the moment (I am making them in advance because my real job means i am not around as much as i would like, based out of the Middle East at the moment) so whenever you are ready.

 

[LDM 3200]

Hi what sort of price are they?
Not needing one at the moment but thinking ahead.

 

[lovellracing]

Thanks All,
Throttle body is on its way back to RRE Reman (for the third time) they will have it tomorrow. I do have a spare throttle pedal gizmo Davy what sort of money do charge? ........Don't suppose you fancy some Karting
Ray, Matchams Karting, Bournemouth

 

[Spartacus]

send it to Mike Roberts at the maserati shed . he will modify it for you and it wont ever do it again . see wheeler dealers Maserati 3200 episode

 

[conaero]

Mike, quite rightly so, won't touch a previously modified TB, he only refurbs unmolested units.

 

[jluis]

Having attempted a rebuild on a unit myself, I can understand Mike position on this.
It's hard to do without causing damage and the calibration procedure is something that could only have come out of a shady Chinese engineer head...

 

[davy83]

they are 350 plus shipping. i have not checked in a while but i think still cheaper than the Bosch unit. Should outlive your car easily and once set up also should never need any attention and never wear, i made one to solve the problem on my car and have made a few since for other owners, the car is tricky enough to keep running without having a flaky highly expensive pedal sensor that only lasts about 3 years, so i thought i would fix that one for good! pm me i can send you more details.

Hi what sort of price are they?
Not needing one at the moment but thinking ahead.

 

[redsonnylee]

send it to Mike Roberts at the maserati shed . he will modify it for you and it wont ever do it again . see wheeler dealers Maserati 3200 episode

After two TB replacements mine is now with Mike being upgraded to contactless. If I had researched a little more a few years ago it would have been done before replacing them.

 

[lovellracing]

BBA Reman did this unit in the first place (modified to contactless) it has gone back under warranty once before. It was only on the car for two weeks until the problem occurred again. It is down to them to repair it. They have had the unit two days now I called them yesterday and today someone is supposed to be getting back to me ........they have not yet, I will keep you informed

Ray

 

[Contigo]

Had this on a contactless too.

 

[lovellracing]

I managed to talk to someone eventually this afternoon who said so far they cant find anything wrong with it

 

[Contigo]

What pedal potentiometer do you have? Standard Bosch one?

 

[lovellracing]

Yes Standard one