'96 850R Very low mpg, very low power.

bmessina · Post by **bmessina** » 04 Feb 2013, 10:38

Post-baby update - I didn't drive the car at all over the last month.

Did 2 things yesterday - Charged the battery (was completely dead) and replaced the TPS. No change from previous poor running condition when I drove it this morning.

bmessina · Post by **bmessina** » 09 Feb 2013, 22:31

Wish I could update the first post with what I've done so far, but anyway - Just checked/swapped out the ECU and coil with known good pieces today, no change. I've also checked the battery ground, looked good and tested good.

Making an appointment with the Volvo guy down the street. I'm officially out of ideas.

bmessina · Post by **bmessina** » 13 Feb 2013, 11:07

Day 1 at the shop - The shop owner said he was out of ideas, and called in an "expert". It's a Volvo shop, so I'm not sure what that means. I'm letting them have another (billed)hour with it, then I'm taking it home.

Post by **rmmagow** » 13 Feb 2013, 12:43

Is it possible there's a clogged converter involved here? My converter on a 98 V70 seems to be totally shot, heavy rattling at idle but shields are tight. I don't have any Converter related Cels at all but on occasion the car feels pretty down on power.

bmessina · Post by **bmessina** » 13 Feb 2013, 12:57

Yup, I had that thought last month and checked it. Seemed fine, replaced it anyway, no change. Wish I could edit my original post with all the checking/replacing I've done...

Post by **erikv11** » 13 Feb 2013, 13:19

On page 1, was the rotor replaced recently and then the trouble started, or do you mean you replaced the rotor (and all the parts in that list) as part of troubleshooting but replacement didn't help?

The rotor has internal electronics and can they go/be bad while appearing fine externally. I'm just reaching here, I know ... Sounds like a very systemic problem, like maybe bad contacts or wiring at the ECU.

bmessina · Post by **bmessina** » 13 Feb 2013, 13:29

I replaced the rotor as part of the stage 0 process. It didn't help.

I haven't checked spark strength at the plugs, I might try that. After that check, I'm going to (carefully) start checking the contacts/wiring at the ECU. Based on how that jump start shocked (hah) things back to normal for a minute, it has to be electrical.

Post by **northernlights** » 13 Feb 2013, 15:59

bmessina wrote:As is the standard, I grounded the dead car somewhere other than the battery. The bracket for the throttle spool, specifically. Yeah, I'll be checking my grounds

For a SWAG, maybe run a ground wire from the bracket to chassis and a similar to the battery negative?

Post by **E Showell** » 14 Feb 2013, 07:57

If hard starting is part of your symptoms, given the carbon on the plugs, it is possible your problem could be due to a bad engine coolant temperature sensor. They do fail and cause driveability issues including an over-rich mixture.

Post by **erikv11** » 14 Feb 2013, 09:51

Smart post, check it!

'96 850R Very low mpg, very low power.

Re: '96 850R Very low mpg, very low power.