S70, 2000, shaking uphill and rough idle

hud304 · Post by **hud304** » 22 Dec 2009, 08:20

This all started happening on a cross-country drive yesterday night, so any help is appreciated.

I had been driving on the interstate for about 10 hours when my car started to have trouble going up slight inclines. At around 1800 RPM, it starts to "slip" or "shake". It's like the power is dropping out for little bursts, a few times per second.

If I back off on the throttle and go to lower RPM, the shaking goes away. If I apply extra throttle and go to higher RPM, the shaking goes away.

I've got a leak of oil or transmission fluid on my crankcase, so I thought that maybe the transmission fluid was low. I happened to have a quart, so I added about 0.2 quart. It's hard for me to get a consistent reading on the dipstick, but it's between 'cold' and 'hot', so I figure the level must not be too wrong. Anyway, adding the fluid didn't help.

While driving 20 minutes to a hotel, the 'check engine' light came on and then started blinking. Eventually the blinking stopped but the light remained on.

I've had a rough idle for over a year now, but after last night the idle (in Drive) is even rougher - a lot of shaking.

In may or may not be related, but the ABS light has been on for months (I figured I'd get the guy in Colorado to repair mine eventually, but haven't done it yet).

I'm 10 minutes from an indy volvo repair shop that I'll probably visit today, but any help from the community would be great too. Thanks.

Post by **polskamafia mjl** » 22 Dec 2009, 08:30

W/o codes we're simply shooting in the dark here, but a few drain and fills might cure your transmission problems and repairing the ABS would take care of the ABS light. There is something wrong though since your car threw a code, and by extension the CEL, so you need to read the codes and then we can truly start diagnosing the problem.

Post by **FlyingVolvo** » 22 Dec 2009, 08:53

If the Check Engine light was blinking, that indicates that your engine is misfiring which obviously would lead to power loss and rough idle.

When was the last time you had spark plugs replaced? I would replace those and make sure the coils are in good shape. Make sure to replace anything with OEM Volvo (or if you want cheaper plugs, get Bosch Coppers).

Post by **polskamafia mjl** » 22 Dec 2009, 08:58

Make sure they are gaped to .028"

Post by **confused_al** » 22 Dec 2009, 12:41

I do not have any answers but do have questions.
How long have you had this car?
Whats the status of your ETM? Software updats, replacement?
In case you want know more about ETM, here is the link;
https://www.matthewsvolvosite.com/forums ... m.php?f=12

hud304 wrote:I've got a leak of oil or transmission fluid on my crankcase

When was last time your PCV serviced?
BTW, ATF has to shoot up to get to the crankcase.

hud304 · Post by **hud304** » 24 Dec 2009, 14:23

Thanks for all of the suggestions. It turns out that I just had a bad coil.

Many thanks to Swedish Import Repair of Oklahoma City, which managed to fit me into their busy schedule and get me back on the road within an hour of showing up!

To answer your questions, last year I had changed my spark plugs, checked that my PCV system produced slight negative pressure at oil dipstick, and had Software Update 155, related to the ETM.