1999 V70 Tachometer drops and Car dies with No Error codes

[sagewhitesage]

I'm Original owner of my 1999 V70 with 300k miles and have an anomaly happening where I need the creative minds to help narrow down what part should I replace and in which order as everytime I take it Volvo or to any other mechanic My Volvo doesn’t present herself with what I am experiencing. Frustrated but this car's engine runs excellently.

Consistent problem I'm experiencing:
-tachometer starts to drop immediately below 1000 and starts to sputter and then engine goes limp including power especially when I am slowing down to turn or a stop light.
-Only the battery light and the check oil light and the Up Arrow light displays on the dashboard when all power is off.
-75% of the time if the tachometer starts to act up and I can safely pull over to stop and put the car immediately and park and just gun it to try to run gas through the engine and then it behaves ok afterwards.
-If the car shuts dow it will start up 50% of the time with no problem or I have to gun the gas for a few seconds and then it drives normally afterwards.
-I get NO Volvo codes (courtesy of the last 2 years replacing parts)
-I may be driving with my foot on the gas pedal driving on freeway or a city street at 40 mph and then sometimes it feels the engine doesn’t know that I’m giving it gas and may drop by 5 to 10 mph for about a few seconds and then it recognizes that I still have my foot on the pedal. (I recall my fix experience of this about 2 years ago but didn’t think anything of it until this year where it’s happening often. So I’m thinking whatever is happening this is the major symptom that may be the causing the go limp shut down of the car when I slow down.
-I may pull out of my garage and then I would see the tachometer starting to go under 1000 and a little shaking occurs as if the engine isn’t getting any gas thought I may be pressing on the gas pedal. I put it in park and press on the gas pedal for a few seconds then it idles happily.
Other days, it happens then when I get down 100 yards and decelerate to turn right and the car goes limp with power shutting off.

I have replaced in the past 3 years:
Fuel Pump
Fuel Pump Relay
Both O2 Sensors (May 2014)
Air Mass Sensor (Feb 2015)
Installed latest software in on board computers from Volvo (Aug 2015)
Replaced vacuum hose under manifold (3/2013)
Replaced many other hoses that contribute to Evaporator Leak error codes along with a few smoke test to smoke out any holes from 2013-late 2014.

Had a retired Volvo mechanic check who had the tool/computer to check if my electronic throttle module is the culprit. After checking he said the ETM is not the problem. He suspected the ignition switch may be the culprit but I had that changed in 2008.
I talked to my former mechanic for 7 years in my former state and he suspects it is the Idle Air Control Valve. (When I called Volvo the part was $300. Can I buy an after market one)

[abscate]

You can buy a junkyard IAC valve but you will have trouble putting it in, because your 1999 doesn't have one.

They symptoms sure sound like a ETB that is dying but if the ETS light isn't coming on that's usually accompanies ETB problems. Has the ETB ever been replaced? If not, you have the worlds longest living Magnetti Marelli ETB.

I think you need to check all your battery cables and grounds carefully. Dying on turns is indicative of bad cables

[sagewhitesage]

Correction: I didn't replace the Fuel Pump relay but the Fuel Pump Ignition relay.

Yes, the ETB was replaced years ago by the Volvo dealership but I need to confirm when they open up.

I will have a check on battery cables and grounds carefully.

I decided I would go to the Volvo dealership as from the weekend the issues was happening often.
Of course, when I started the car and drove out my neighborhood it hummed like a new car. No issues as I'm drove to the dealership which is 10 mins way.

Then one of the senior mechanics hopped in the car and drove it with me riding. So he started driving fast and after a few minutes while driving on the roads (not freeway) he was able to feel a misfire of some sort. Then magically the 'check engine' light came up. I was excited.

After 2 hours back at the Volvo shop he came out and advise me of the following:

-Checked Fault codes ECM 150A air mass Flow sensor. Lower Limit.(**my comments-> I just had the AMF replaced brand new in February for the same thing that I am experiencing now by another shop. **).

-Checked the Fuel Pressure is at 45 PSI. Check for vacuum leak and PCV systems is in OP. (***The volvo mechanic said it would be good to perform the PCV service for all intake hoses but not now until I test my car out for a day or two of the things he did***)

-Checked and Cleaned the ETM. Throttle Body and it passed the test with no issues. (****I have never changed the PCV or ETM in my vehicle.**)

-Check the Spark plugs look ok.

-Check and replaced Air filter since it was dirty.

-Found the Fresh air door is not opening which needs the Air box to fix. I opened the door temporary and see if it takes care of the running issue. Recommend PCV Service if it still has the running issues. (**Mechanic either force this door open for now to see if this may be the culprit**).

I just drove the car on the freeway in the heat of the day for a couple of hours and no problem so far. However, I'm not optimistic as this is only a guess for now. My long term mechanic who is out of state doesn't believe this door or the PCV will resolve the problem.

So I will see in the next few days how the Volvo operates.

[sbwga]

Hi,
I read your thread and was wondering if you could tell me the final fix? I am having the same issues and it is hard to pin down. Any feedback would be greatly appreciated.

[sagewhitesage]

Hi Sbwga

Well time has passed and I think I finally nipped it in the bud but it took about a year to figure it out. Here is chronological items from my last posting:

-When I went to the Volvo dealership they gave me the same mechanic that works on the hard to figure out cars. So he couldn't find anything except he noticed the air fresh hose that recycle air would not stay open. So he figured let's force it to stay open to allow the engine to get fresh air. Maybe this was the problem since the This lasted about 6 months and I was a happy camper.

Then it started again....

-I found a shop from Yelp about a volvo mechanic who only works on volvo and their rates are better than the dealer. (The Vo-Vo shop Inc in Phoenix, AZ). So I went. When I called before I told him I had a 99 volvo with 300,000 miles. He assumed (like other mechanics) that I was bringing in a beat up car. When I arrived he was shocked to see the body of the car (original..never been repainted) and the engine looking good. He knew he was dealing with a lady that spends preventative maintenance and good car of her car. I actually listen to my car and have it check it out versus ignoring it. He actually found a couple of original parts in my engine and was shocked but I take care of it besides having a volvo angel watching over my car.

He Spent 2 days troubleshooting and finally did a smoke test to find a pin hole in one of the hose. He kept it for a day to test drive it and again the TAchometer dropped and car died. He already had told me it will take a few days. I was ok because I needed so desperately for him to figure out what others couldn't.

-He scanned ECM and the fault codes were:
*ECM 150A Air mass meter sensor lower limit (I had this air mass meter replaced 1.5 years ago at another local Phoenix shop so this particular one didn't last. I have to make sure I ask for geniune parts that are known to last years).

*ECM 250A Fuel Trim Lower LImit

*760A INMOBILIZER COMMUNICATION FAULT

#1)He found the air mass meter failing ( though I had it replaced 1.5 years ago).
#2)He found a very clogged oil trap hose and this was preventing my engine from really performing and even functioning. When he replaced this I couldn't believe how good my engine was humming like a tuned race car. I realized this hose was slowly over the past year or two contributing to my engine not breathing at capacity. I read up on this part and realized it may have contributed to other pressure leaks from the short past (http://www.myswedishparts.com/how-one-r ... -thousands)

#3)After testing and a day drive..the mechanic noticed the tachometer wanted to on occasion make a slight movement especially when he was at a red light but maybe 1 out of 20 times he would see this. So he knew that it could only be the Engine Idle Value. He replaced it...test drove it for a day,off and on to try reproduce. Fortunately, this took care of it.

#4)He also replaced the Air Fresh hose (that the previous Volvo mechanic Mcgyver'd to stay open).


Since November 18, 2016 I have had not a single issue with this ongoing idle issue. I don't drive my Volvo much but I currently have 308,500 miles on it. Though I have spent a several thousands in the past 2.5 years on wear and tear items like on suspension, joints, bushings, brakes, etc but I can say the Engine is operating like it did when I bought it 16 years ago.

Good luck. I'll continue to post if anything should creep up in the next year.

[abscate]

Congrats on the long running life , your Taking care of your car has paid off!

You don't have an idle air valve on this car but there is a valve for managing vAcuum for the brake system which can be confused for an IAC.