Engine Shaking, Ready To Give Up On My S80

[renzo86]

So, where should I start? A year and a half ago (or longer..) I got this 2000 S80 T6. I've been through a lot (and i mean A LOT) of repairs and replacements. The most expensive one was sending the car to rebuild the tranny. I have replaced oxygen sensors (4), catalytic converter, PCV oil trap, heater core (all vaccuum lines replaced), boost pressure sensor (just today), purge valve, alternator, battery, intake manifold gasket, ETM (yellow label), and some other components from the suspension (control arms, etc etc etc...).

After the tranny was rebuilt, I noticed the engine shaking for some reason.. ?? I took the car to the shop where they rebuilt the tranny. The guy said they never touched anything in the engine. He also said tranny doesn't have anything to do with the engine. ??? I'm not so sure about that. I took my car to more than 4 shops and had them scan the computer millions of times already.

Right now I'm at the point to give up on this car. What's left to do? Rebuild the engine? Will that take care of the check engine light and the shaking ??

Any thoughts? Comments?

thanks everyone! This forum has been my main tool for all the replacements I mentioned above! I'm greatly thankful for all the info provided!

[t10opila]

You mentioned scanning for codes, were any present? (if so, what are/were they?)

When do you encounter the shaking, all the time, highway speeds, low speed, braking, accelerating, rainy tuesdays?

Just need a little more info, and I'll see what I can do to help

[boosted5cyl]

I know the feeling about wanting to give up. When is the engine vibrating? Does the CEL flash at all?. What codes have been pulled from the car? Off the cuff it sounds like a possible dead ignition coil and or tired/incorrectly gapped sparkplugs. Either of these issues could cause damage to the cats and O2 sensors.

If its vibrating at idle, you can try disconnecting and reconnecting the fuel injectors one by one while it is running and observe how the motor behaves to isolate the poorly behaving cylinder(s). Search youtube for a "power balance" test. They may say to disconnect the igntion but I am not a fan of that as you end up dumping raw fuel on your cats and o2 sensors. Its easier to pull the injector connectors anyway.

Investigate these possibilities before you go anywhere even considering a motor rebuild.

[renzo86]

Thanks for the info boost.

The last code I had them pull out was P0238 which relates to overboost and who knows what else. I replaced the boost pressure sensor and I noticed some improvement while accelerating from 0 to high speeds. Before this replacement I had engine or transmission hesitation between 55mph and 65mph. I tested drive the car yesterday after replacing the BPS and I believe that problem is gone!

While parking my car the check engine light showed up again!
I guess I need to scan the ECU again.

Regarding the engine shaking, it shakes at idle. I remember now that they guy who sold me the car had sparkplugs that had 3 sparks on each. Did you guys think that kind of sparkplugs affected the engine over time???

Well, the CEL is on again. Engine still shaking like if something was really pushing the whole block.

I'm gonna disconnect the injectors one by one and see if there's any difference. Besides that, I'll unplugged the coils and will try to see if the spark is going through. I'll also check the sparkplugs for correct measurement.

[renzo86]

Okay so I spoke too soon..! The hesitation when I'm going on the freeway between 55 and 65 mph is still there. It feels like transmission doesn't know what to do... ??

Also check engine light and message ENGINE SYSTEM SERVICE REQUIRED are on.

I'm ready to call a junk yard!!! Grrrr!!!

[fn42]

I remember now that they guy who sold me the car had sparkplugs that had 3 sparks on each. Did you guys think that kind of sparkplugs affected the engine over time???

Aren't the 3 prong plugs for non-turbos only? that could definitely cause some misfiring

I may be mistaken though

[cmblackburn]

Engine mounts?

[renzo86]

Checked engine mounts already. It feels like something else. Could it be compression on each cylinder? Any suggestions on how to perform that kind of test?

Those sparkplugs that I mentioned the car had before, are only good for some models. I checked online and they are not compatible with my s80 T6. I'm just guessing that could cause some engine damage. Maybe? Maybe not?

[boosted5cyl]

Sounds like you might have a misfire and or boost surging. Hard to tell over the internet. Could also be a torque converter not locking up. How does the car pull if you do a WFO run in second gear?
For the plugs, if it was my car, id pull the plugs that are in there out and put basic copper plugs in, gapped to .026"- .028". No splitfire, v-gap or any other nonsense. Simple down to basic copper plugs. The only problem with the coppers is they have to be changed more often but they are cheap.

Yes, scan the ECU again, get the codes and post them up.

[fn42]

Checked engine mounts already. It feels like something else. Could it be compression on each cylinder? Any suggestions on how to perform that kind of test?

Those sparkplugs that I mentioned the car had before, are only good for some models. I checked online and they are not compatible with my s80 T6. I'm just guessing that could cause some engine damage. Maybe? Maybe not?

Incorrect spark plugs probably won't cause any damage, but misfiring over a log period of time could mess up the catalytic converter

get those 3 prong plugs out!!! go to the volvo dealer and get the OEM t6 plugs


start with the plugs, if those don't help test the compression to start narrowing it down. If you have a cylinder with really low compression it's most likely something internal (read: expensive)

edit: as far as TESTING the compression, you need a gauge that screws in to the spark plug hole. Disable ignition (pull fuel pump fuse), start it and let it run till it dies, then screw the gauge in and crank it for a few seconds. Repeat w/ each cylinder