It appears the throttle return spring is broken on my 97 XJR..

Part number is NBD3030AA

I called 2 different forum sponsors and both said it is no longer available from Jag..

Anyone have a used one? or know how I can get one?

I think it has to be specifically for the XJR as the same year XJ6 part number is different..


EDIT. Terrys didn't have one in stock, but they checked Jaguar and found 1 in the US..
They are trying to get it and will let me know for sure tomorrow..

 

Kev,

McMaster-Carr (mcmaster.com) carries a good selection of springs and I was able to find an extension spring of the correct length, O.D. and wire size to match the one on our N/A '93:

McMaster-Carr

I ordered a few different springs so I could evaluate their spring rates because I was concerned about the spring being either so wimpy that it wouldn't close the throttle, or so strong that the accelerator pedal would require too much pressure and make my foot ache. I had hoped to land on a stainless steel spring, but the one that worked best was finished in black oxide and had a spring rate of 1.74 lbs/inch (item 3114T77). I have no idea if the spring you need will be similar, but if you order one from M-C that has a similar length, O.D. and wire size, you'll have a good chance of it working.

Here's the diagram for the X300 supercharged throttle body. Part 7 is the return spring:


Another thing you may want to check is the accelerator pedal return spring, Part 2 in the diagram below:



It would also be worth checking to ensure the throttle cable is not corroded, gunked up or kinked.

BTW, M-C also carries torsion springs and I found one that was a good replacement for one that broke in our driver's door handle.

Cheers,

Don

 

Thanks Don..

Wondering if anyone has a service manual that has the steps to replace the spring?

It's pretty buried under the cover there.. not out in the open like a naturally aspirated car..

Raining again here and my truck is in my garage so I can replace the
stsarter, so I don't think I'll get the car on ramps today to look from underneath..

 

It's been a few years, but.....

I recall that the spring can be replaced from underneath if your manual dexterity is fairly good. Or you have eyeballs on your fingers. One or the other. You can see the spring, and you can reach the spring with your fingers....but you can't do both at once.

I also recall that if you remove the intake elbows and ducts you can see and reach the spring fairly easily from topside.

Cheers
DD

 

"Appears" ? Have you looked at it?

There are two return springs, actually. The linear spring already discussed and a coiled spring on the throttle shaft itself. In the back of my mind I think there was a Jag TSB suggesting that both be changed for something stronger.

Are you having a high idle problem?

Cheers
DD

 

hmmm.. Dons diagram shows just one, but I do recall seeing a different kind of
spring on the forum that was part of a recall but I assumed it was for the regular
motor, not the supercharged motor as it isn't pictured above?

I'm making an assumption that the return spring on my car is weak or broken based on
the behavior.. With the car off, if I floor it and let go of the pedal, the throttle
body only returns half way.. the last half is 'floppy' like there is no tension on it.
I can easily flip the throttle closed by pushing it with a dowel from the topside..
No resistance like it's gummed up or stuck.. it's just like a spring isn't keeping
tension on it.

If I start the car with that 'closed' it fires right up and idles fine (although slightly high)
but if I blip the throttle a little it revs, and doesn't come back down till I manually
return the throttle body mechanism.. So there is some measure of tension on it as
it does return to about half throttle, but it doesn't return the rest of the way.

Car is certainly not driveable the way it is right now..


edit: I just stuffed my iPhone down in there and snapped this picture..
The coiled springs on the throttle body shaft appear intact, but the black
rod the arrow is pointing to is hanging limp..




.

 

I'm dubious of how much help it will be to your situation, but here is the no-cost mod to accomplish the TSB on the NA car:
https://www.jaguarforums.com/forum/x...carman-111454/


NA version doesn't have any rods nor tension springs from what I recall.

 

If the throttle body has never been cleaned (to your knowledge) it is way overdue. They get gummed up.

Also, the throttle cables might need adjustment.

Cheers
DD

 

I got the new return spring and installed it this afternoon.. It certainly helped the
situation, but did not completely fix the high idle.. It will come back down to 1200 or so,
but I still need to manually close the return the rest of the way to get it to a normal idle.

The supercharged motor is exponentially more difficult to clean the TB on..

It looks like major disassembly is needed..

My car runs sweet, no hesitation and smooth power.. just doesn't return all the way to base idle.

Tomorrow I'm going hunting for a stronger return spring before I tear down the things
in the way of getting to the TB.. (you had to see the contortionist moves needed to get the spring on)

 

Did you slacken and then readjust the throttle cables yet?

Depending on how far you plan to take things apart you might wanna consider replacing the octopus hose at the same time


Cheers
DD

 

i know this is a stretch with this being in 2014 but how on earth did you acsess both springs without taking the throttle body out i can get to the one spring easy but the coiled srping that goes around the throttle shaft i cant even seem to find. 

 

how on earth do you acsess this spring on the supercharged motor I can see on of the two but the second one is not only impossible to get to but I can't even manage to find jt anywhere and I really do not want to take out the throttle body if I do not have to

 

Hi 96 xjr cole,

Welcome to the Jaguar Forums! It's great to have you with us.

These springs are probably no longer available from Jaguar, so your best bet will be to source a similar size spring from a supplier such as McMaster-Carr (mcmaster.com).

Please visit the New Member Area - Intro a MUST and post a required introduction so we can learn something about you and your Jaguar and give you a proper welcome.

Cheers,

Don

 

My post disappeared?
I posted the recall/TSB that was issued a few decades ago.

I replaced dozens and dozens during the campaign.

The original spring can also be used if you wind and extra turn and trim the spring end off.

 

Bob,

96 xjr cole is inquiring about a supercharged engine. Does the TSB also apply?

Cheers,

Don

 

Page 2.
Note: On 1995 MY XJR vehicles not previously reworked under
R493, the only repair to be performed under T493 is to replace the
throttle spring.

Page 13.
REPLACING THROTTLE RETURN SPRING – SUPERCHARGED ENGINES
1. Remove the intercooler induction elbow retaining bolts and clip.
2. Remove the elbow, hose and sealing ring.
3. Disconnect the cruise control vacuum hose and the return spring and remove
the retaining nut and the actuator.
4. Disconnect the inner accelerator cable from the throttle assembly.
5. Loosen and remove the three Torx head screws that retain the throttle
assembly cap to the pedestal and remove the cap sub-assembly.
6. Unhook the throttle torsion spring (Illustration 9) from the throttle shaft
actuator and then remove the spring and the sleeve from the shaft.
7. Remove the sleeve from the spring and discard the spring.
8. Insert the sleeve into the replacement spring. Install the sleeve and spring on
the throttle shaft and hook the spring on to the actuator.
Note: Tension (pre-load) the throttle return spring by rotating the
straight extension one full turn counterclockwise until it can be
installed in the same position as the original spring.
9. Carefully reinstall the cap to the throttle assembly noting the lever location.
Install and tighten the screws.
10. Reconnect the accelerator cable to the throttle assembly.
11. Reinstall the speed control actuator on the mounting bracket with the
retaining nut.
12. Reconnect the vacuum hose, linkage pin and the return spring.
13. Reinstall the sealing ring on the induction elbow and then reinstall the elbow
on the throttle assembly with the retaining bolts and clip.
14. Check the operation of the throttle assembly.
15. Remove fender covers, reconnect the battery, reinstall the battery cover, and
close the lid of the luggage compartment. Reset the vehicle clock and
customer preferences.
16. Using the WDS, perform the oxygen sensors orientation test. (Select set-up
and configuration, engine and transmission, oxygen sensor orientation.)
17. Using the WDS, perform the throttle potentiometer adaptation test.
Note: During the throttle pot adaptation test portion of the engine
set-up procedure, the WDS will ask if a new throttle position
sensor has been installed. Answer this question with YES even
though the existing sensor is being reused. This action will allow
the WDS to reset a larger set of parameters.
18. Check for the presence of any erroneous diagnostic trouble codes (DTCs). If
DTCs are present, they should be recorded, and then cleared.

 

thank all of you guys this is definitely gonna help me out alot also i made a post in the new member thread about me and my car I belive I did so right if not I apologize just let me know and I will fix it. happy to be apart of the forums!

 

I'm currently in the process of accessing the spring I'm on step 3/4 and I'm having a lot of trouble, how exactly do I get the screw out that holds the vacuum on and how do I go about getting the inner accelerator cable off

 

I got the things off and the new spring on but upon inspection I belive that thr other spring is bad as pictured how do I get this one out and where do I find a replacement please help I am currently in the process of doing this and need to know soon