V70 Erratic idle, no power

Mookie · Post by **Mookie** » 23 Feb 2018, 22:48

Today, my 1999 V70 abruptly lost power. At idle, with the transmission in P or N, the engine lurches back and forth between about 700 rpm and 1200 rpm. In P or N, I can rev the engine by pressing the accelerator.

In gear, there's no throttle response whatsoever. The idle continues to oscillate, and the car rolls a bit in response, but stepping on the gas makes no difference at all.

For what it's worth, the weather has been very rainy for the last several days.

Thanks to any and all for your help.

Post by **rspi** » 23 Feb 2018, 22:55

Check your fuses.

Mookie · Post by **Mookie** » 23 Feb 2018, 22:56

Which one(s)? Is there a particular circuit I should look at?

WhatAmIDoing · Post by **WhatAmIDoing** » 23 Feb 2018, 23:42

Are you using a KAE fuel pump relay?

Post by **abscate** » 24 Feb 2018, 04:50

If you have over 150k miles on it, the throttle body could be near end of life.

Your description sounds a lot like limp mode, which is what the car does when that part dies

Any lights on on dash?

Have pending codes read at an autozome or buy a cheapish reader that's will read pending codes ($35 or so)

Post by **wizechatmgr** » 25 Feb 2018, 00:06

Make sure the battery isn't low... When I had an alternator go I experienced the same symptoms when I went well below 12.5V. Once the battery was charged back up I had no further issues.

The ETM can be tested with VIDA. It gives a pretty little graph of both of the varistors sweep and the deviation from expected.

One other trick - put the car on a charger and place the key in "on" for a half hour. Come back out, turn it off, then start the car. I know I pissed my car off rather badly by not exiting the ETM test correctly. When this happens it will hit limp home mode for a time.