'98 V70 XC - Two problems,

mindshadow · Post by **mindshadow** » 10 Jan 2014, 09:57

1st - So, my coolant light came on but there's plenty of coolant in the overflow tank. Car isn't running hot. Is it possible the sensor is just bad?

2nd - I'm having some problems getting the car started. In the morning it's usually fine and will pretty-much crank right up, although there seems to be a fair amount of smoke that comes out when it first cranks. In the afternoon when I leave work I usually have to give it some gas to get it cranked. This all started after I took my car to the shop for a pretty big oil leak, which turned out to be near my turbo (the return line perhaps? I forgot). I've checked and don't find any vacuum leaks or anything. I suspect the PCV system may be involved, since there's so much smoke in the morning and I've seen smoke coming from the dipstick, but I'm not entirely sure how that could be the case. The PCV job was supposed to have been done a while back, but perhaps the mechanic didn't do a good job. :\

Thanks.

Post by **kcodyjr** » 10 Jan 2014, 15:18

1st - check the wire connector to the sensor, and if it isn't loose, trace it back. There might be a wire break.

2nd - if you have smoke from the dipstick, you have either a PCV problem or failing rings. If the mechanic that did the PCV wasn't a Volvo guy, you're right to suspect his workmanship.

What color smoke in the morning?

mindshadow · Post by **mindshadow** » 10 Jan 2014, 15:49

Blue. Definitely burning oil.

Post by **kcodyjr** » 10 Jan 2014, 16:24

Blue smoke means oil was burned under compression, as opposed to gray/black smoke from burning oil in the open. That means it's getting into the cylinders through the intake stream. If it was coming in through the PCV system, you shouldn't be getting smoke at the dipstick. I therefore suspect the turbo's internal seals.

If it was a non-turbo-related leak, such as a bad stem seal or piston ring, I'd expect it to do it all the time.

That said, it's possible that you have rings just beginning to have a blowby issue, that goes away when the metal expands after running for a few minutes. Does the dipstick smoke go away when it warms up?

Do you have a compression tester assess the engine's internals?

Post by **MoVolvos** » 10 Jan 2014, 19:37

_

Viscosity and type of oil can make a huge difference - Read entire post
https://www.matthewsvolvosite.com/forums ... =1&t=59045

Change to this and if the smoke lessens in the morning you know it is the rings
http://www.walmart.com/ip/Shell-Rotella ... l/14958681

My 98 S70 T5 with 231K was gushing oil from the dipstick when purchased. Non-stop billow and wet engine. Couldn't drive it had to be towed back after purchase. After the PCV still had smoke in the morning but within 6 months of using the 15W-40 the morning puff was gone. It is almost 2 years now (3rd oil change in Nov 2012) and still no puffs in the morning at 245K. You can take the time to do a variety of test or a quick oil change to the Rotella or wider ranged viscosity Dino for a quick test on the rings.

Blessings,

BKM

_

Post by **kcodyjr** » 10 Jan 2014, 20:09

BKM speaks the truth. Dino oil has the advantage in an internally worn engine.

I don't think we've gotten to solutions yet, though. We're still working on diagnosis.

A compression tester is a less invasive test than switching oils.

socompsp · Post by **socompsp** » 11 Jan 2014, 00:11

is your CEL on? you should be able to call the shop that did the work and get info on the exact service done. in the mean time remove the upper intercooler hose and clean it. after a day of driving you should be able to see how much oil is going into the intake (if any). this will indicate internal turbo leak, and how bad. as stated the color of the smoke indicates burning under compression, so the leak wouldnt be on the exhaust side of the turbo. the only other place that i can think of where oil can enter the combustion chamber is through valve guide seals, and through or around the piston. you more than likely do not have a cracked piston as that would cause a loss in compression and CEL to illuminate. let us know how it goes.

Post by **anjill182** » 11 Jan 2014, 03:40

The smoke and hard starting may be due to a bad injector leaking fuel.

socompsp · Post by **socompsp** » 11 Jan 2014, 11:13

anjill182 wrote:The smoke and hard starting may be due to a bad injector leaking fuel.

huh? im curious to hear your reasoning behind that thought.

Post by **rspi** » 11 Jan 2014, 11:51

1. If the low coolant light is on, check the bottle and make sure the plug is in good on the bottom. Then rock the bottle to make sure the level float is not stuck. Not sure why it would get stuck all the sudden but who knows.

2. Hard cold starts may be connected to a bad ECT (coolant sensor going bad). Could also be low fuel pressure coming from the pump. Try turning it on, then off, then trying to start it next time. Maybe priming the pump/fuel like will help.
Also, these cars at this age are know for having valve stem seal leaks which allow oil to leak past the seals while it sits. Then at start up you will get some smoke until it burns off. Does it smoke after sitting idle a while?

Go to 8:30 in this video: