Lessons Learned

[Bill]

As anyone that drives a 944 Turbo is aware, a mechanical issue can rear its ugly head at any moment.

Mine happened today on the drive from Carpokes world headquarters in Norcal to Las Vegas. While driving over Pacheco Pass in Gilroy I heard a “Pop” and the engine started bucking violently. What the hell?? I backed off the throttle and the engine smoothed out. What the hell?? Back on the throttle…repeat.

What I came to understand is the issue only occurred when the turbo came on boost. So rather than stop, I drove the remaining 500 miles below 3000 rpm, naturally aspirated while it was still running. I watched my AF gauge and EGT gauge closely and as long as I kept out of boost, there was no fear of a lean condition that would destroy my engine.

I made it home, opened the hood at took a peek. What I discovered was the rubber hose that goes from the turbo to the intercooler hard pipe was blown off and was resting half on half off the hard pipe. Reconnected the hose and had a happy engine under full boost (22 psi) again. Had I chosen to open the hood earlier I would have had the usual very enjoyable drive instead of a butt squinching one limited to 80 mph max and the zero acceleration of a 944 NA not a 400hp turbo.

So, there you have it. To the subject of this topic, this is my lesson learned. If you encounter the engine bucking, only under boost, raise the hood and check your turbo to intercooler to intake hose connections.

Tom…what do you think, maybe a section on “lessons learned” for everyone to share their issues and resolutions for all to learn from? Maybe help with a quick fix on similar recognized symptoms?

[Darwin]

This happened to me several times as well. For me it was always at the throttle body. The last time it happened, it actually moved to the drivers side and jammed against the throttle body linkage, forcing it to stay wide open. My engine bounced off the rev limiter for a few seconds but no harm was done.

[Tom]

Sorry that happened Bill, but glad you made it home. The last time that happened to me was 'the last time that happened to me.' I ended up welding on boost braces to my pipes so they cannot separate. The final straw for me was when a coupler blew off on 280 and I was a couple miles from the next exit. The car would start and run for maybe 2 or 3 seconds before dying (MAF disregarded for start-up??) -- I limped off the freeway by starting it and coasting 100 feet at a time, over and over. A downhill section helped a lot too. There was a CVS right at the exit, so I went in and bought a screwdriver and was back in business, but I immediately started plotting the weld-on braces. In the interim, however, I tightened worm clamps around the metal part of the tubes and secured them with metal straps to nearby fixed screws/bolts.... It wasn't pretty, but the couplers never came off with the pipes secured like that...