Snap! Pow! Vroom!!! Clunk,clunk,clunk... gosh, now what!?!?!?

[skinnerd]

Yesterday, cruising at 70mph on I-84 heading back to SW Portland after the workday, it happened.

All of a sudden, I heard what sounded a big pow in the back of the car, and then my 2.7MFI engine began revving to the moon. What the ....!!!! Well here I am in rush hour traffic out in the passing lane 3 lanes from where I know I need to get to really quick. As I'm headed to the right side, I'm hearing this loud clunking from the back. Oh, I somehow got it together to turn the ignition off, so I flip the key on again and yep, the engine starts revving way too high. Off I turn it. Did I tell you one of the pedals went to the floor boards when all this began? So my mind is racing... trying to figure out just what happened while trying to get the car to a safe location for later towing.

Somehow I do it. The car is on the top of the exit ramp (not sure how I coasted that far) and in a safe place where hopefully some bozo won't plow into the rear of the car. When I look under the car, one of the axles is visibily disconnected from the transaxle and just hanging there. Great... somehow the bolts backed out all the way. Raising the hood, the shafts to the throttle bodies were stuck in the wide open position.

To make a long story a little shorter. Two hours later AAA Plus had deposited me and Rudy via flatbed towtruck to the street in front of my house. PO'd, I went and had a beer to digest all that had happened. The only thing that really concerned me was the possibility of over-revving the engine to the point of bending valves. This engine has a cutout at about 7400rpm, but I may have revved right past that with no load on the engine and the throttle bodies wide open. Any thoughts out there concerning this?

Later last night, I pulled my floor jack and jack stands out to the street to start assessing the damage. Sure enough the driver side axle had come disconnected at the transaxle. Three bolts were completely missing, and and 2 of the 3 remaining were bent to ****. The flailing driveshaft dented up the SSI pretty good, and completely took out the throttle linkage (it's MIA) between the car body and the little bellcrank by the MFI pump. If there was a support for this linkage on the side of the transmission, it was ripped completely off. CV grease was everywhere in sight. That will take me an entire evening and 3 rolls of papertowels to clean up. Luckily the drive shaft didn't punch a hole in my trans or any other vital organ. Continuing into the engine compartment, I investigated the cause of the linkage being locked up. The reminants of the throttle linkage shaft that the CV joint took out was positioned just right to hold the throttle bodies wide open. In addition, the impact damaged part of warmup snorkel for the MFI. There's a flapper that opens after the engine warms up that won't open any more as the plastic cam that rides on part of the throttle linkage was broken in half by the impact from the CV joint.

I was able to hacksaw off the bent CV bolts and borrow a couple from the other axle (my goal was to get the car up the hill and into the garage for the evening). The engine started up but is backfiring massively (again I'm worried I internally damaged the engine from the over-rev). Instead, I am able to just use the starter and 1st gear to get the car up the hill and into the garage. Mission accomplished! I can easily order the missing/damaged parts. I will need to somehow remove the broken stud on the side of the transmission where the linkage support used to reside. Afterwards, I will need to conduct a leakdown test to see if there are bent valves.

Just didn't need this, but I've read of others problems on this board, and they always get through them. Next time I'll be using Locktite on the axle bolts... that's the lesson learned from this adventure. All-in-all, I'm lucky that I didn't get hurt (imagine this happening at a track event coming into a corner at about 90?). The car will certainly be repairable and I'll learn some useful things from the process. Hopefully, there are no bent valves, but that remains to be seen. This is nothing that a couple a (dozen) Hefeweizens can't help. Thank God for Pacific NW microbrews.

Anyway, thought you'd enjoy the story and just something else to add to the memory banks. I know it's hard to think straight when you're in the middle of a crisis... just ask me, I was trying. I'm sure I didn't catch the over-revving motor quick enough and I'm not sure the rotor rev limiter could either. Things happened so fast, and the next thing I knew I was sitting on the side of the road.

[Tim Walsh]

That really sucks. I know it's on my list of things to watch out for after you and porsche_virus have had troubles. I think it'll go with the 3000 mile checkup

[Wayne 962]

You're lucky - it could have been much worse. I'd say you got off easy, as I have heard of flailing axles flipping cars over on the track.

The only real way you can over-rev your engine is if you downshift into the wrong gear. Sounds like the rev-limiter did it's job. Not a pleasant sound, but I'm sure that your engine is okay.

-Wayne

[masraum]

I have experienced the same thing, but it was at a very low speed and in a Dodge Omni that used a VW tranny with 6 allen bolts (sounds familiar doesn't it) Glad things came out relatively well. Keep us updated.

[pbs911]

Sorry to hear this. It could have been much worse. I have heard of the axles tearing off the headers and really doing some damage. Mine did the same thing but it happend just as I was pulling away from a stop light from a dead stop. Since that time I check the torque on the CV bolts at least once a month. Some do back out. Checking these bolts should be part of your normal monthly routine.

[skinnerd]

Thanks Dr. Paul... it will be from now on.

[HarryD]

Doug,

Ouch!

Hope the scope of the damage is limited to the few places you already know about. If you need a hand, I'd be glad to help out as best I can.

Hope Rudi is on the road soon.

[rcwaldo]

If I ever have the inner cv bolts out (in the 993), I am drilling them for safety wire. Easy to do and cheap insurance...

Hope you get your car repaired soon!

Chris

[Superman]

Roninlb has drilled and wired his CV bolts, and though I am not one to over-react, I certainly could not criticize this decision. I'm with Wayne on the rev limiter thing. If it worked, then it would have limited revs to 7400 or wherever it's set. In other words, I'd guess your engine is fine unless the limiter failed to work.

If the throttle linkage nipple was busted clear off your tranny, then I would think this might be the worst of the troubles. You may have dodged a nasty bullet.

[widebody911]

I had an axle let go years ago, and it beat the holy carp out of one of my brand-spankin-new SSI's. Of course, back then a set of SSI's was only ~$300 (I found the receipt a while back)

[jmz]

ouch! Doug, that motor is bullet proof and I'll bet all is fine.

[Schrup]

I think I would have soiled my britches. I hope your motor is ok & you have it back on the road soon. I'm going out & check my CV bolts right now to stave off any nightmares tonight.

[finadict]

why wouldn't your insurance cover the damages caused by the CV failing? I know the CV isn't covered but it seems to me the damage it caused would be, especially if the engine is hurt.

[kepperly]

A similar incident happened in my 77 930 back in 86. pulling to the top of first gear and bang,bang,bang,bang. on the brakes hard and after a look called the tow truck. 6 new c/v bolts on the left and retorque all of the rest to the recommended 90ftlbs
instead of 45 that my wrench had " thought " was right, I got to drive it back to Wichita, Ks. From Oklahomia City, Ok. with the exhaust sounding like an old VW with the heads loose, and breathing all of the exhaust that was now presurrizing the interior of the car instead of the turbo. What a hangover from that. Good luck my friend, hope theres not anything serious.

Keith 87 slant nose turbo look cabriolet carrera

[Sonic dB]

Pardon my newbieness....could someone explain what drilling and wiring the bolts is all about?

Do you drill a hole in the head of the bold, then run a wire through and secure the wire around something? perhaps the tranny? I dont get it...

[kepperly]

You drill all six then run a twisted safty through each one and it prvents them from unsrewing more than a 1/4 turn.

keith- 87 slant nose turbo look cabriolet carrera

[Doug Zielke]

Originally posted by Superman
Roninlb has drilled and wired his CV bolts,

So did I.
And so should everyone.
It's not that hard.

[osidak]

I had the my drivers side inner cv drop when pulling out of a sears parking lot. rolled maybe 5 feet. sheared 3 bolts mangled one and the others where missing. After trying to do a quick repair in the parking lot I called a flatbed and had him drop it at the house where I had a friends 911 torn apart putting chain tensioners and turbo tie rods in,

[Dantilla]

So is "Kermie" your daily driver for the next little bit?

I may still have some of the throttle linkage parts that you damaged out in my garage. Let me know what you need.

[Rod911]

English is not my native language. Can anyone explain the word "rev" to me?

thx