Hello All,

I have a 1999 V70 AWD XC wagon with 265,000 miles. Today, I noticed the idle was uneven as I stopped at a traffic light. As I accelerated from a stop, the car began to stumble slightly lightly. I was near my destination, so I parked the car got out and attended to the errand. Upon my return I started the car, and it immediately started and stalled out with a bunch of "idiot" lights coming on, including the "Check Engine" light. The car started, and all the lights went out, but the idle was erratic jumping from 800 rpms to 1,100 rpms and back down to 800 rpms. I was able to drive the car home, but slipping it into neutral and stepping on the brake with my left foot and feeding it gas with my right. I drove 20 miles this way on highway and back roads before getting home. When I pulled into the driveway, the car did not stall out, but the idle continued to rise and fall between 800 rpms and 1,100 rpms. There are not "Idiot Lights" on. Does any have an idea what could be causing this? Thanks in advance to all who respond.

Hugh

Hello All,

I want to express my thanks to you collectively. Your advice about potential vacuum leaks was correct. My mechanic performed a smoke test on the engine and found several vacuum leaks and fixed them all. Since then the idle level has remained consistent. He said he did a check for error messages and did not see a "Check Engine" light code. When I dropped the car off, all the "Idiot Lights" including the "Check Engine" light were off and have remained off. The "Check Engine" light only came on the first time the engine stalled.

I am very thankful it was not an ETM. That was an expense and inconvenience I am glad I was able to avoid. Again, thank you for your advice, you have confirmed the value of this website.

Hugh

If your ETM was replaced by a yellow tagged module, you should be good there.

Yes, I agree with the others, check for vacuum leaks. Any hose that might supply air to the intake manifold is suspect. If you let this go on too long without fixing it, you will get a check engine light indicating mixture too rich or too lean.

There are some vacuum lines that are hard to see, like under the air intake box and under the air intake to the throttle body. All original vacuum hoses need to be replaced soon, they get old and crack with age.

When the rpm's get too low, the alternator will stop functioning and ALL of the idiot lights will come on.

--
Keeping it running is better than buying new

Klaus,

You mentioned a "yellow tagged module". I don't know if the replacement ETM that was provided by Volvo via an extended warranty did or did not have a "yellow tag". Tell me what a "yellow tagged module" is. Thanks, you forever pull back the curtain of ignorance for me.

Hugh

Replacements had a yellow tag, the original 1999 had a white tag. ALL 1999 ETMs failed,, including the one that came with your car. The replacements do not fail.

Glad you got the vacuum leaks fixed!
--
Keeping it running is better than buying new

Yes check all of the vacuum hoses. One that caused me a problem was from the underside of the inlet trunking at the front panel to the inlet manifold. Quite a small bore hose. With it off the computer thinks the engine is running weak and increases the fuel too much. Have you recently changed the air filter? Taking the lid off can pull things around. It's possible you don't have a vacuum tree. I have a 2000 V70 and I don't seem to have one. Mine is non turbo.

It sounds like a fuel issue, failing fuel controller
Check for vacuum leaks.

Why haven't you registered with Brickboard?

Bill

Bill,

Thank you for your reply and suggestions. I am worried it is the ETM failing. I have had it replaced on this car twice (both times under warranty).

I haven't registered for Brickboard because I do not know how to do so.

Hugh

Hi Hugh,

Click "Subscribe"
or go here
https://www.brickboard.com/contribute.shtml
Fill out the profile to enable private email, etc.

Good luck, Bill

+1 on what Bill said.

I’d start with vacuum leaks. Any loose hoses? How is the throttle body hose? Maybe hidden splits? Also check the vacuum hose tree. In particular, look for old hoses with hidden cracks and splits at the ends.

--
Will I buy another Volvo??? We'll see....

JWalker,

Thank you for your response. You give me hope that it may not be the ETM that has to be replaced (for a third time).

Hugh

Hugh,

I realize that 99’s can be prone to failing ETM’s. Never had one go bad on me. Did the check engine light (or any other lights) come on when your ETM failed before? Hopefully it is a vacuum leak. Have you replaced any vacuum hoses on your car? How about the throttle body hose? If not, they are probably due.

Jim
--
Will I buy another Volvo??? We'll see....