I've looked around the forums and couldn't find any posts with the same issues that my car has had.

A few days ago when I had the A/C on, the car went into limp mode with the EML, DSC and Service Engine light coming on. I turned off the A/C and was able to park within a minute. There was no smoke or anything, but maybe a slight burning smell from the A/C. Turning the car back on showed no problems, just the service engine soon light on.

Today I took the car to Advanced Auto Parts (A/C off, no service engine light or warning lights on) and got the P1688 code. Would anyone be able to pinpoint if the problem is more the crank pulley or the bypass valve knowing that the problem was caused from the A/C?

Thanks for the help.

 

Hit the search button for this forum and you're going to see a lot of information on this. Actually there's probably 3 threads that are still current from the past week that have all experienced your issues.

A/C on causes extra load on the drive belt system. Long story short, not sure what model year you have but the harmonic dampers tend to crack in the rubber that mounts the inner metal crank snout piece and its outer metal drive belt pieces. Extra load from A/C being on can cause this failing damper to slip which will instantly slow the belt which will instantly drop the boost the supercharger produces which will then set this fault.

You're not going to want to replace the harmonic damper with another OEM unit because they all eventually fail. Waymotorworks sells both a fluid/gel filled unit as well as the ATI super damper which many prefer. Either way, these fluid/gel replacement dampers are less expensive than the dealer replacement and will last the life of the vehicle.


Another search on the forums here and you will find how to remove and replace the damper. About an hour or two hour job. Can be a DIY if you have basic mechanics tools.

Remove RF wheel.
Remove RF wheel well liner (plastic screw clips and T30 torx screws)
Remove Drive belt (belt removal tool can also be purchased by Way or other mini vendors)
Remove large bolt holding harmonic damper on.
Use damper removal tool to pop off damper (it is press fit onto the crank snout)
Install new damper and torque NEW bolt (this bolt is a torque to yield, One time use bolt).
Reinstall fender liner and Reinstall and torque wheel.

 

Here's plenty of thread results from search:

https://www.northamericanmotoring.co...archid=7868655


Also, Welcome to the boards. Get it fixed fast and happy motoring!

 

Yup sounds like your ready for an ATI damper crank pulley, get that and you won't have another failure.

 

Bypass valve is 100% not the issue...if stuck open, car just runs fine, but no boost...just like below 3000 rpm...if you smelled a burning smell, i think waymotorworks hit it right...the crank damper is failing....once the rubber starts to slip you may be a few feet from needing a towtruck....

 

There's been a rash of Crank Damper failures as of late, a lot of the cars are starting to get "that many miles" on them + the really hot summer hasn't helped.

 

Mine failed Sunday on the way home from the grocery. Car went into limp mode, with all the lights on and a burning smell. ATI has been ordered from Way and the car will be back to running again by the end of the week. Car just turned over 101K with the OEM crank pulley.

 

I'm in on this 1688 code. Happened today. Same as all, EML and limp mode. When I let it cool off, I was able to drive (gently). Once it warmed up, went to leave, boom into limp mode. Had it towed home and tore the liner off. I see a lot of "rubber dust" around the crank and idler to the right. Crank feels solid though. I do have a burning smell. Not 100% sold on the crank as it looks 'new'. I bought the car with 65k and it has 85k now. Thoughts? I also notice on my boost gauge the needle has a slight flutter to it as of the last few days. I'm not opposed to spending money, I'm just opposed to wasting it by throwing parts at my car. Anthony at out motoring suggested the crank or a failing tensioner. For the record, it's an 06 R53.

Edit: has a slight rattle noise at idle that goes away at 1500-1800 and gone at a rev to 3k. After a few revs engine sounded normal and rattle came back sporadically.

 

Here's a video link of my noise...

http://instagram.com/p/gyfTtftyZR/

 

Hoping someone who's heard that sound will chime in. Thanks for the video.

I was looking for a thread I read a while ago,.. Can't find it now. It suggested a way to "inspect/test" the crank pulley. If memory serves, they said grasp the bottom of the pulley with your fingers, pull out slightly and then tap on the crank pulley with a rubber mallet. If you get pieces of rubber falling into the palm of your hand, then you've proved that the rubber in the pulley is beginning to deteriorate. -not sure if it's a fool-proof test or not, as I wonder if it could be possible to pass that test, yet still have a separating crank pulley?

Do you have the tool to take the tension off the belt? If so, it wouldn't be too hard to do that so that you can turn by hand the idler pulley, see if there's rough spots or play in the bearing.

The hunch I have is that with the rubber dust, the crank pulley is on its way out, and I will not be too surprised if you discover that the tapping sound you hear is the pulley brushing against the engine (timing cover) right behind the pulley.

Too bad it's such a pain to get the pulley off (well maybe not too much, especially with an impact wrench and the correct puller). I was thinking that if the task is within your ability/tools, and if you might have a slight oil leak behind the pulley anyway (many of us do) -then you could replace the seal, and then replace or reuse the pulley depending on what you find when you remove it.

 

I definitely can pull they pulley. I tore apart my Subaru engine with hand tools, so I'm not shy about doing this. Just don't wanna buy a crank pulley if it's the tensioner.

 

I hear ya on that. I don't like to buy parts unnecessarily. I'm going to get a tensioner myself soon. It bounces a lot, and I know the damper strut thing is blown, I can telescope it way too easy by hand when it's off. The only noise it makes though is my WMW tension stop vibrates. Does not sound like your at all. I'll be getting the Gates Tensioner from Amazon, it's like $80 -sweet deal.

 

P.s. if you do remove the pulley, don't forget to get a new bolt regardless. It's supposed to be replaced and not reused.

 

Somebody else should listen to this video

Bump

 

I just went out, took my pry bar and tried to wiggle the pulley. It's solid, it was lifting the motor. Is it more in/ out movement and not up/down? I was prying from the back side using the tubular frame part below the pulley as my leverage point. There definitely a ton of rubber dust between the crank and the idler to the right. It seems like the top (not grooved side) is glazed.

I just have all the usual symptoms...burning rubber smell and EML/ 1688 code once it warms up. Strangely though I have boost flutter around 10psi.

Here's another thing, every so often my car will barely idle. Sounds like I have a huge cam and my DSC light will come on. It's only happened a handful of times and more frequently recently. I also get an O2 and knock sensor code when it's hot outside.

 

Is your belt stretched, slipping?

Still doesn't explain the sound. Do you have a super long screwdriver to hold the handle against your ear and carefully touch the other end to various stationary parts of the engine?

So Bentley is showing that P1688 is Low Mass Air Flow. A related component is EDR electronic throttle actuator. There's a pair if potentiometers provide feedback of the position of the throttle plate and the position of the D/C motor that is supposed to open and close it. If the feedback signals are inconsistent a fault condition is assumed.
The other related component is of course the supercharger. Here's a much better test for you:
Mark the pulley with chalk line from the crankshaft bolt to the drive belt. Run engine and inspect marks. Chalk marks misalign if pulley fails.

 

The 1688, burning smell and noise all happened together. The belt feels nice and tight, no cracks and based on 85k on my car and I SUSPECT a new crank/balancer and belt went on at some point. The top non grooved portion of the belt looks glazed bug nothing crazy. The belt dust could be old, I'm just not sure.

I just idled the car, at cold it had the noise in the video. A few light blips of the throttle and the noise vanished. I turned on the a/c just to add a little load and it rattled like crazy. Listen here...

http://instagram.com/p/gyxoYrNyeh/

Also my check engine light is out and I did not reset it.

I'm stumped. I'm all for purchasing parts from a vendor if they'll chime in...way, outmotoring, chime in!

 

I guess I could always pulley the crank/ balancer and tensioner and inspect them...

Also, Alex; in muuuuuch searching of the 1688 code and seeing the TB/bypass replacement - I didn't find anything that said that was the cure. 100% seemed to be the crank.

The sound is NOT coming from the SC, I'm 100% certain. It's just right around the crank.

But what sensor would put it into limp mode!? That just seems odd. Are these cars that smart?

Also the burning rubber smell...I mean EVERYTHING I've read says the crank/ balancer is the culprit.

 

Yeah, I think the crank pulley is the most common.

As I understand, the sensor that trips the light is the MAF, it detects that's there's not enough air flowing for the throttle position and rpm and trips the light. ((edit: MAF trips the light AND limp mode, probably good thing that it makes it limp, because the water pump is running slow too)) The cause (most commonly i believe) is that the SC not spinning as fast as it should and thus not creating enough airflow for the given rpm and throttle position.

I too hope Way will chime in. I'm kinda like you, that I've always worked on cars, but I've only had my MINI for about 9 months. Learning a lot thanks to this forum. I've bought stuff from Way and other vendors that sponsor the forum. He's got the best deal on the brakes I want, and it's only a matter of time (2005 86k miles now) -I'll get an ATI damper from him too.

 

bump

 

Sent an email to Way and he diagnosed the pulley. So, looks like I'm getting an ATI. Hope he has the 2% pulley

 

Actually I'm doing stock diameter pulley and the 17%er I've been eyeing up for a year. Might as well since I'm doing a new belt and all. Went with Way's pulley pack (17, belt, plugs). Also bought an sc pulley puller.

 

That's awesome. I'm still torn about the pulley size. But I'll most likely do the crank pulley and sc pulley at the same time. Last week I put in all of the PowerFlex bushings. I really like them, and the little bit of vibration doesn't bother me really -the slight vibration is only there at idle anyway, BUT I was thinking that the ATI might smooth it out a little.

Let me know after your install if it really seems a lot smoother. Im always re-prioritizing my list of mods and maintenance; the ATI is moving higher on the list.

 

I had a Svt focus from 02-05, built the motor and had a nice turbo on it; pushing 423 at 21pso on pump gas (93). I had upgraded motor mounts so I know the vibration. I enjoy that and cam lope.

I will definitely keep you posted.

 

I haven't pulled the codes, but I just bought an 02 MCS that is doing the same exact thing...limp mode, etc. I can reset the car by restarting it, drives fine with normal input, but when I get on it, there is hesitation at various RPM's depending on speed and gear selection, and into limp mode it goes.

Watching the video, i was seeing that the harmonic balancer was spinning a little off balance. Also, couldn't see it very well, but the idler pulley (the stationary pulley) seemed to be slow spinning in respect to the belts speed. Just my input on what i saw.

I agree 100% with the above mentioned responses. Again, i am experiencing the same thing, and am smack in the middle of replacing my harmonic balancer with an ALTA 0%, the belt with to a quality race quality belt, and for kicks, i've got a detroit tuned by-pass-valve pending install. Figure i will report back one each thing is done and see if it solves the issue. My gut tells me i am starting to experience a combination of two things: belt slip and balancer starting to fail. This is a second car, so its parked right now. All the parts above ran me right around $280. I've got the harmonic balancer puller, and belt tensioner tool, so i'm good with that.

I wish everyone experiencing the same issues as us 'limp mode' peeps the best. If you want to check back with me sometime later i will be happy to discuss my outcome. I am hoping to have all the parts installed by the end of this week, weather providing.