Edmunds dealer partner, Bayway Leasing, is now offering transparent lease deals via these forums. Click here to see the latest vehicles!

Volvo S70 Starting Problems

bobkolbobkol Member Posts: 2
I tried to start my 1999 Volvo S70 AWD Turbo. It acted real rough, kept stalling and black smoke came form the exhaust. I was able to limp it home but it will not even start now. I know I have a bad downstream O2 sensor, but I don't think that would cause all of these problems. Any ideas?


  • knoltingknolting Member Posts: 1
    We are having the same problem with our '98 s-70 what did you find out and how did you fix it???">
  • muuramenianmuuramenian Member Posts: 3
    No black smoke, but ours was running rough and stalling before it gave up completely. New mass airflow sensor cured it.
  • bobkolbobkol Member Posts: 2
    I ended up changing both O2 sensors. At first I changed to downsteam sensor and it was better, but still sluggish. But once I changed the upstream sensor the problems went away.
  • jotjot Member Posts: 4
    You should have a check engine light on. You need to read the codes, Auto Zone does it for free. Has this problem just started? If not you are probably going to need a "cat" as well as the Front and rear sensors. Check-out "Matthewsvovlosite.com", "Brickboard.com" or "Volvospeed.com"
  • cindyroucindyrou Member Posts: 2
    I have run a carfax and it comes back clean. It does not list any dealer maintenance, however. I am going for a test drive tomorrow and will be asking for maintenance info, because it appears the previous two owners (one for over 100000 mi) must have used someone else. It has 126,500 miles on it. It looks great, and I am looking for your opinions. I need a car that will be reliable for a very long commute (65 mi one way) and that will get me at least 100000 miles until I can afford a new car.

    I live in central Alabama, and I am hoping there might be someone on this forum who can give me some maintenance info and costs for the area.

    Most of all, and I guess this is a question for you gentlemen on the forum, would you feel comfortable putting your wife, sister, mother or daughter in such a car for such a long commute (in the wee hours of the morning, by the way)? And, considering that money is a huge issue here, what kind of upkeep am I possibly looking at?

    Also, what are the questions you would ask if you were considering purchasing it?

    Thanks very much for your advice and help!
  • joe162joe162 Member Posts: 1
    Problem: No start (crank but not run), water coolant sensor, radiator fan relay.
    Model: S70, 1998, 2.4 engine.
    Situation: Will not start (crank but not run), when cold
    plus cooling fan runs after cranking engine.
    Repair items which made no difference:
    new fuel filter - located by passengers rear tire = $30.
    new spark plugs - located engine center under top cover plate (Bosch +4) = $35.
    new battery = $65. - love that squeeze type connector.
    sensor MAF mass air flow:
    located in top corner of intake air filter box.
    yes engine will stall when repluging in connector - shows it is working..

    Repair items which solved the problem:
    sensor water coolant temperature: (eEuroparts.com $30)
    plug located by thermostat just under top radiator hose.
    unplugged sensor = cold 5.00 K ohms, = hot .36 K ohms.
    other side of plug to ECU = cold 5.56 K ohms, = hot 5.59 K ohms.
    yes if you run engine with this unplugged check engine light will need resetting.
    reset using DTC plug with ODB reader with reset - or Volvo dealer.
    plug located in arm rest by drivers seat.
    Engine would not start when cold because Electronic Control Unit, (ECU) viewed the engine as warm. This was indicated by the cooling fan running after the no start cranking.
    No there was no DTC codes showing.
    No check engine light was not showing
    No the fan relay was not defective.
    No the fuel filter was not clogged.
    No the fuel pump and check valve was not defective.
    No there was good spark to the ignition.
    No the key switch was good.
    The water coolant temperature sensor seemed ok, did not check to be bad.

    How to get running even with this no cold start situation.
    (1st way) Open up air intake by loosing hose clamp on rubber flex hose, slide hose back,
    Add 3 or 4 tablespoons of raw gasoline.
    Start the engine, with full throttle peddle.
    This will provide enough fuel to start the cold engine.
    The engine will run because there is nothing wrong.

    (2nd way) Unplug water temperature sensor
    (slide connector off tab holder, squeeze the lock, unplug the two wire connector)
    Start the engine. Proves this to be problem.

    The problem is the ECU does not provide more fuel for the cold start up because it considers the engine as warm.

    Solution: Unplugging the water temperature sensor, this allows the engine to start on a cold 40 degree morning. During this situation of running engine with everything cold and the sensor unplugged apparently the ECU reset itself. After this I simply repluged the water sensor and problem was gone, with exception of check engine light. However this only lasted 2 days then problem reappeared. Then would start only if you turned the key 2 times. Then would not start at all. I then unplugged the temperature sensor and instant start, (rough running until warmed).

    I installed new water temperature sensors, problem solved, very easy to do. You don't even have to drain water from radiator (will be a small fluid spill). Remove thermostat cover (Torx screws) unscrew coolant sensor, screw in new one, reinstall thermostat cover, connect wire for sensor, job done, add a little coolant.
  • brkncarbrkncar Member Posts: 1
    My friend has a 1999 volvo s70 2.5L turbo that will not start and I cannot figure out what the problem is. A little backround on the car: it was stolen a while back but recovered, we have no idea what happened to the car while it was out of his possession. When we got it back the intercooler was broken but we replaced it and it ran fine afterwards.
    He was driving down the road few months later when the oil light came on. He put some oil in it, but it took a while to crank it to start. That lasted for a week until it died whle driving down the road. Then it still took a while to try to crank but never quite turned over, and the battery would drain before it would turn over. so now we have checked the filters and injectors ant they all look fine. the coils all have cracks in them, could the be shorting out through the head and not be getting any spark to the plugs or is it somthing different? We are going to do a compression test soon and i will let you know what the results are.
    I know problems like this are hard to describe over the internet so if you have any questions, i will do my best to answer them, any help that you could provide would be very useful. Thank you in advance!!!!!

  • gmac50gmac50 Member Posts: 6
    I've put a fuel pump..filter and mass air flow sensor in it and it still stalls...no codes or check engine light comes on
  • robk6836robk6836 Member Posts: 2
    Any ideas on a cold starting problem? My 98 S70 requires several key turns to start when the outside temp is below 30. I replace the coolant temp sensor, and the thermostat. When I turn the key I noticed that the radiator fan is running, even at a cool start. Is this normal?Once the engine does start it idles down and turns off, which I have to restart and give a little gas pressing the gas paddle before it will run on its own.

  • thehats00thehats00 Member Posts: 2
    Here's an FYI to everyone who has had this problem. I have read countless posts and followed much useful advice. I changed the temp sensor, the fan control relay, the maf sensor and the fan ran continuously. I finally found that none of these parts had been bad. When changing the temp sensor, I failed to notice the tremendous amount of corrosion inside the positive terminal of the sensor connector. Cleaned this, put dielectric grease on it and it sured the hard starting, the fan running and the lack of boost from the turbo. $250 in un-needed parts and several hour in wasted labor all because of corrosion in a connector. Always check the simple things first! Apparently a bad signal from the temp sensor causes multiple problems such as hard starting, fan override that forces the fan to stay on in 'safety mode' and it also tells the ecm to kill the turbo boost. Hope this helps.
  • steven807steven807 Member Posts: 1
    Battery is a few months old and strong. Car was not starting quickly. Today it ceased to start. No reaction upon turning the key. Tried jumping - but not necessary - battery strong, headlights and accessories unaffected. How do I diagnose this? How do I test the solenoid and then the starter?
  • sickwithitsickwithit Member Posts: 1
    Love my Volvo. Have not had bad problems with it until now. It will die while idelling and then not start/run back. It will turn over like it wants to start but won't. I get occasional exhaust smell and bad mileage. I average 22 miles to the gallon. Saturday I got 12. It has died sitting at lights. I've had to put it in neutral, foot on brake and gas in order to keep it running. Sometimes it will start and run with no problems, sometimes not. It even hesitates while driving down the road. When it started I thought I had gotten bad gas. In two months I have replaced the catalyc converter, 2 vacuum hoses, and the air flow sensor ( 3 times). :mad: When hooked to a computer it says air flow, so we initially thought we were getting bad parts. My mechanic has even taken it for a second opinion cause he's as stumped and aggravated as I am. Any suggestions? :sick:
  • jrobertsrook1jrobertsrook1 Member Posts: 1
    Hi my 99 s70 will not start after replacing the radiator. I had to disconnect alot of electrical wires which ran across the fan shroud and reconnected them. The car turns over but will not start. I did not disconnect the battery while I did the change does this matter?
  • richsrichs Member Posts: 3
    I have the exact same problem at present! HELP!!! I hope you can reply to this and help me find the solution!!! It would appreciated..Thanks ...Frustrated
  • bgalebgale Member Posts: 1
    Hey my name is Brett I have a 95 volvo 850 turbo and anytime the temp is below 35 deg it takes a good 20 minutes to get this car to crank and stay running I tried your solution and it crunk in the 2nd attempt you are the man thanks so much for your info it may just save my JOB . I'm on my way to purchase a new temp sensor.
  • mitchem1234567mitchem1234567 Member Posts: 1
    I have a 1998 Volvo s70 none turbo I just replace my starter but when in turn the key the headlights go off and the motor.wont crank one turn over

Sign In or Register to comment.