A little more than a year ago I decided to do the clutch pedal helper/booster spring removal modification. For you that are not familiar with this mod, it basically involves either removing the pedal helper spring all together or using a weaker spring witch in turn definitely makes the clutch feel and use much better in my opinion.

Of note is that the stock spring is very strong which in turn keeps the pedal all the way up tightly against the clutch delay switch. This will turn out to be key in my experience.

The clutch delay switch has two functions: 1. It disengages the cruise control should one depress the clutch pedal while using the CC. 2. This switch is also called a delay switch. It slows/ closes the throttle plate for a fraction of a second everytime the clutch pedal starts moving downward or is engaged. I believe this is to make shifts smoother for those who don't have the best shifting skills.

Here is where things went bad for me. I tried several weaker springs and finally went with a very weak spring. By doing so, my clutch pedal would sit not quite all the way up and not quite resting on its own weight. That meant that the clutch delay switch would be right between on or off. This caused all kinds of intermittent issues.

Not long after this mod I decided to do a bunch of performance mods: turbos,injectors,IPD,throttle body, intake, IC's,clutch and so on.

I've been chasing gremlins for almost a year, incredibly frustrating. I posted several time trying to find the issues. At one point I absolutely hated my car because of these gremlins. At the time I though my issues where from doing all the performance mods or perhaps a bad ECU or a bad tune. I turns out the issues were because of the clutch switch being in a "limbo" position, somewhere between on or off. I replaced every check valve, solenoid, wheel speed sensors, FPR, O2's and so on. I replaced a buntch of stuff that I didn't need to chasing these issues.

My issues where intermittent, impossible to replicate and very random. Depending where the switch was, on or off, would determine if I had issues. Hitting a bump in the road or if my foot was resting on the clutch pedal just before a shift would cause weird thing to happen. The data logs showed that at times, very weird things where going on with the throttle plate/DME.

I finally figured it out when my foot caught the back side of the clutch pedal causing it to go up fully against the switch. I felt a slight "bump"/hesitation very similar to the VarioCam bump. I tried it over and over again and sure enough, if the switch was released or partially released, It affected the car and how it pulled. WOT or aggressive throttle inputs with the switch in limbo were awful.

If you are looking to do this mod, make sure to either:

Use a spring that keeps the pedal up against the switch
OR
Completely remove the switch and tape the switch completely in. Do not disconecting the switch as this is the equivalent of having it in the delay mode not to mention your cruise control will not work.

I ended up completely removing the spring and simply pushing the switch completely in and taping it in all the way. I also have the switch tie wraped way out of the way.

Now I can say that 90% of the drivability issues I was experiencing are now gone. Unbelievable!!

Hoppefully my year + nightmare will save someone the same aggravations I went through. If you are having drivability isuues, check the clutch delay switch.

I have to give a HUMONGOUS shout to Sam from ByDesign and Mitch from COBB tuning. Sam is the best, incredebly patient with unparalleled customer service.


Karl

 

Holy smokes, quite an ordeal for such a simple thing. Glad you got it sorted!

 

go to home depot and ask for this sku #684838 in the hardware dept. there are 2 springs in the pack. use the longer soring. its just enough to hold the pedal from kicking the cruise out but soft enough to think theres no spring at all in the setup.

 

Thanks, I'm all set. I like it better with no spring at all. It lowers the pedal a bit and I like the quicker throttle response without the clutch delay switch kicking in.

 

Interesting, I have never heard of the clutch switch and throttle connection. Who confirmed that the switch affects the throttle position (aside from you and your experience)? I removed my spring and have had my cruise control working intermittently because of it, but haven't noticed any other issues. I've done a lot of data logging and have never had my throttle position change at wot. Maybe it wasn't doing it then and I've never noticed it at part throttle.

 

There a few post about that switch and the " delay" function it serves. Some of the track guys chimed in about it and the benefits of deactivating it. I think because my pedal was right in between on and off it caused some additional issues. If it stays either on or off while driving I think it doesn't cause any issues. It's when it goes back and forth between on and off while accelerating problems arise. Kinda a tug of war going on.

Just as an experiment, drive in 3 rd gear on flat ground around 3000 rpm. Make sure you pull up on the clutch pedal to have it tight on the switch and then keep a constant speed and throttle pedal position and push on the clutch pedal about 1/2" just enough to activate the clutch switch but not enough to make the clutch slip. You will feel a very slight deceleration even though your foot did not move on the gas pedal.

Now keep in mind I have a lager throttle body, air intake, IPD plenum and injectors. I suspect all these mods may accentuates the "bump" sensation. I did not notice this when my car was stock.

 

Wow, nice find! I have been checking up on your other thread from time to time to see if you got it resolved.

 

I can't tell you how frustrating it was for everyone involved, myself, my mechanic and the tuner. I literally wanted nothing to do with my car for several months. I've put less than 1500 miles on it in the last year.

I think it was a "perfect storm" type thing. Had I completely removed the spring I would not have had any issues. The spring I used simply put the switch in a bad spot, continually teeter tottering between on and off. I had no idea what was going on since I never use cruise control.

Thanks for your concern.

 

Good to know and I'm glad you've got it sorted out. I man up and ust the GT2 spring, good workout for the left leg. I don't think that a frail woman would be physically capable of driving my car however.

 

Talk about a wild goose chase full of gremlins! I really appreciate your kind words buddy because you're actually one of the most patient people I've ever dealt with. You never pointed the finger and you always stuck by us. I really appreciate that! Sorry you have to deal with this and if I knew about it we may have turned on a few lightbulbs but honestly it was just a wild ride. I'm really glad you can enjoy the car now!

 

Thanks Sam, I'll bee doing logs this weekend...Finally we can do some final tweaks on the tune instead of chasing gremlins.

 

Nice that you got it figured out! Sam has been helping with me with a gremlin of sorts as well after several upgrades. I can also attest what a testament to customer service he is. His pride in what he does and service to his customers is unmatched!

 

Damn, that sucks! First I've heard of there being any sort of torque management going on but that sounds like exactly what it is. Like everyone else my switch is intermittent however I found the plunger could be extended to reach the pedal by tugging on it. Sadly if the clutch comes all the way up I think that gets reset Really do NOT like that spring but to get cruise working on my ProEFI the switch needs to work - ugh!

 

I don't know what your ProEfi does but you can still remove the spring and have the CC work. You simply tape the switch with plunder all the way in. The CC will work fine. The only function that won't work is the clutch pedal CC kill switch.

 

guys your making this to hard. the home depot spring is super light. less than a couple bucks and keeps the c/c working as it should without impacting the feel