Hey guys , hoping someone has run across this, I've got an R53 S, one day coming home from work (I'm a german body tech) the car felt like what went into limp mode or just loss a lot of power, check engine was on, pulled over and how luck would have it I had my scanner with me, code was (P1688 Electronic throttle valve control 2/3, air mass calculation) cleared the code went back on my way, and it happened 2 more times in very short order, the 4th time got a the battery light and it started getting hot, so of course I'm thinking it threw the belt, sure enough it broke, and it was twisted up as if it got real hot, so while I'm waiting for a tow truck and my wife, I tried to spin all the pulleys, alt, ac, idler, tensioner, all fine and blower,,,,but not freely, then again I don't know how free it should spin, I did some research and apparently there is an oil cavity on the back side of the blower where the rotors are connected by a couple of gears that the oil should be replaced periodically, based off of the trouble code and the belt breaking, I'm thinking that's were the trouble is, maybe after spinning under a load it gets hot and it starts locking up, I should also mention I believe the guy before me put a JCW over drive pulley on the blower, Any clues ??
And if you think it's the supercharger, what's a good way to go, new , rebuilt, bearings (do it myself), and were would be a trustworthy place to get it from, lots old used blowers on ebay, buy I'm not trusting that so much.

Thank you very much for your time , mike

 

I'm no expert but - just out of curiosity; did you happen to smell any burning rubber before the belt was thrown?
Also, If the car has the factory/OEM Mini harmonic balancer/crank pulley- you can grab a hold of it and try to push/pull it back and forth. Try to spin it and see if it slips or wobbles or if you can see any cracks in the center rubber portion.
The factory crank pulleys are notorious for wear and the rubber will eventually give-way and throw a belt sometimes before they (pulley) even break.
I had a belt thrown when my idler pulley detonated and left me stranded waiting for a tow truck. The precursor/tell tale sign was a high pitched squeal that almost sounded like the SC whine.
The SC pulley should rotate/spin but with a little more resistance.
You may want to take a look at the belt tensioner as well.
IME; Any of these parts above may cause the belt to slip and break loose.

Just a thought.

 

^^^ What he said to start (malfunctioning crank pulley). Rebuilt S/Cs go for around $1,500 so that's more than likely a consideration for most. There are oil cavities at both ends of the S/C. The larger holds 100ml and the smaller, 25ml. The S/C needs to be removed to top the oil. This is normally done at the 100k mark so you need to bounce that against your mileage and also determine if the PO might have already done it or had it done. This is VERY important because it uses oil (special Delco S/C oil) over time just as your engine does. Run it dry and you'll have big problems.

 

F.Y.I.
https://www.northamericanmotoring.co.../market/364253

 

Thanks for the replays guys

 

But the plot thickens, ok, the pulley was bad , I replaced it, put a new belt on (had trouble finding the correct length as the previous owner put an overdrive pulley on the SC) cleared the 1688 code , did a brake job, went for a quick road test to bed in the brakes , all ok, next day went to work after about 1.5 miles it went in to limp mode , check engine light on, restarted it, went another 100 feet, limp mode and threw the belt , scan says 1688, CRAP! 2 weeks later went for the big disassembly, SC off, it seems ok, wtf, so I guess you look for what is throwing the belt,,,,,,,, but I get the code before the belt breaks ??????

I guess the next step is disassemble the SC,,,,,,,

Any clues guys , thx for your time,,,,

 

Not sure I'd disassemble the SC without some clear indication the SC is the problem.

It is a used car. Mod'd. Who knows what was done or done and done wrong. Check the SC drive pulleys are in alignment. Verify tensioner is ok.

 

Thx RockC , tried to upload a video of turning the SC , looks good, all pullies seem ok , tensioner looks like this now from driving the car with no belt, it was hitting the balancer, so it has to be replaced , (should it do that though, hit the crank pulley) the pulley on it is fine and , bearings ok and no wear on the pulley itself, I have no worries in disassembling the SC , I have been rebuilding race motors for years, a blower should be a piece of pie, plus its all ready out and I was going to change the oil , the question is not just the belt,,,,, why is it going into limp mode with a 1688 DTC "Before" the belt breaks??? that's the odd part , maybe the SC gets hot and locks up?? frees up once cooled down,,, thanks again

 

Boy that thing really took a beating. Didn't it ?!
Just curious -
What size SC pulley do you (or the PO), have on there?
Is it possible you may have a mismatched belt?
Or perhaps a failing tensioner might be to blame?

It seems good that you pulled the SC off for further inspection and service/oil maintenance though.

 

What was wrong with the SC pulley? Also, what kind of overdrive crank pulley did the PO install? Did you try marking the pulleys to see if either of them is slipping on the shaft?

 

I would definitely take a look at the crank pulley. They have a rubber center than can separate over time. The inner spins but the outer doesn't spin at the same rate. That would definitely throw a code and likely a belt as well. If the cash is available go with a fluid-filled ATI. If you're a hot rod guy you know the brand. PRW also makes a fluid-filled crank pulley that's less expensive but it's not rebuildable like the ATI.