95 Volvo 960, 170000 miles

[stanleeone]

Just to update a posting from April of 2011... I had a 95 Volvo 960, 170,000 miles, that would not accelorate. It would start fine, but under acceloration it just would not go anywhere - could not get out of its own way. Plus it shifted very hard. I put a new timing belt, mass flow sensor, and throttle control module on it, but there was no improvement. I took it to a shop and after several days, the mechanic gave up; he just said I had a sick Volvo. I took it to a second mechanic recommended by a friend and after having the car for two weeks, he finally discovered the problem. He said the flywheel has an aluminum disc in the center with a circular hole pattern and these holes are used for monitoring the RPM of the engine. The aluminum disc had broken (welds I guess) away from the flywheel and as the engine accelorated the disc would move out away from the flywheel and as a result, the RPMs could could not be read; so, the engine would basically go into a restricted (there is a better word, but I cannot think of it) mode. The mechanic somehow observed this with the engine running and looking through a hole; maybe used a borescope. He removed the transmission and replaced the flywheel and now it runs great. I think this is a rare type of defect, nonetheless, I just wanted to share it in case someone else might have the mysterious problem. Also, I want to thanks those on the forum that tried to lend help.

[billofdurham]

Thank you for this information. It is one fault I have never heard of nor, may I add, has my very friendly Volvo tech.

That mechanic is definitely worth keeping!

Bill.

[tjts1]

Our 89 240 automatic with LH2.4 had the same fault. The crank sensor timing ring would vibrate on the flex plate with an audible metallic ticking sound which cause the engine to lose power. The ring can be rewelded onto the flexplate without removing the transmission.