Hi all,

Our 940 Turbo starting smoking underhood last night after driving for about 20 mins. The smoke was coming from the back left area of the engine, near the firewall close to the throttle cable. I snapped this pic:

http://www.brickboard.com/IMAGELIB/volvopic.htm?js_link=1&id=10784

I will try to get out there in the daylight and replicate, but I'm wondering--even though it seemed seated as normal--if the dipstick had popped up a bit and allowed oil mist to spray the area, enough to get puffs of white smoke going.

Thoughts appreciated.

Hi all,

To close the loop... it was a broken heater valve, the plastic fitting which fits up to the firewall. That was replaced along with its two hoses. Problem solved.

Re: oiliness, I asked for a new dipstick o-ring. Also, I was overdue for valve adjustment, so I had that done as well, along with checks of crankcase ventilation, partly to get a new read on my various slow oil leaks in the context of correct ventilation and a new head gasket.

This weekend I'll get under the car to change the oil and filter, and while there will see how other leaks look (oil filter pedestal, rear main seal have been trickling for a while...)

Thanks again for the input.

Dear Greg R,

Hope you're well. Unless a clamp has worked loose (unlikely) the heater hoses and heater control valve should be replaced. AT ONCE!!!

Absent a loose clamp, the hoses and/or the heater valve have failed. If they're factory-original, they're at the end of their working life or past that point.

Do NOT drive the car even 10 yards, without replacing heater hoses and the heater control valve.

Use Volvo brand heater hoses. These hoses are hard to access/inspect. Volvo brand heater hoses last, reliably, 12-15 years (high ambient temps / low ambient temps).

See the FAQs for the procedure.

Hope this helps.

Yours faithfully,

Spook

Hi Spook, Tom, others...

Yes, I figured if I was losing coolant almost as fast as I was adding it to the reservoir, I would not be driving the car anywhere!

I am up against a wall time-wise so won't have the chance to replace the hoses and valve myself. I went ahead and called AAA and had the car towed to the mechanic. Will provide a final update when fixed.

Thanks all for the good advice.

Can't think of anything on that side that would blow oil. Brake reservoir or master cylinder?
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Post Back. That's whats makes this forum work.

Actually, the greasy looking stuff could be antifreeze residue.

Hi all,

More/different info. As PhilC noted, oil dipstick wasn't that badly seated (still, the O-ring is due for replacement). The REAL problem however appears to be a coolant leak at lower left of the engine.

The other symptoms reported by my son last night and confirmed by light of day:

- Check Engine light.
- Low coolant. (He did not look to see if engine temp ran high as he was busy worrying about the white smoke!)

This a.m. I confirmed very low coolant level; I slowly added several quarts of coolant/water mix to the reservoir, only to find it dripping down the rear left engine block, onto the tranny, and onto the driveway.

The car was tilted slightly rearward by the slope of the driveway; I quickly started up the car and turned it around so that it was tilted frontward. The leaking stopped, although not sure if this was also because it drained to a level where it no longer wanted to leak.

I pulled the engine codes and got only one: 1-2-3, which per the FAQ means "signal missing to/from coolant sensor" and that could mean bad connex, corrosion of ground, etc. (Not sure if coolant is really low it could also throw that signal?)

My visibility to that part of the engine is poor. Questions:

1) Is there a hose or hose connection "down there" that could be broken, causing this major coolant leak? Is this driveway repairable? (If it's a gasket or seal, fuhgeddabowdit.)

2) Can the car maintain enough coolant to get to a garage? (My trusty Volvo mechanic, unfortunately is about 10 miles/20 mins away.)

Sign me,

Goin' nowhere

There are six coolant hose connections there. One under the intake manifold going to the head, two into the firewall, two into the heater control valve, and one behind the block going to a metal tube to the water pump. It is one of these connections or the hose with an equal likelihood that the heater control valve is leaking. Replace all the hoses and the heater control valve. Volvo hoses should be used.

For the oil, make sure the pvc system is clear. Lots of stuff in the FAQ.

Tom

1. Heater hoses going into the firewall.(if it is, replace heater valve unless you know for sure it's new)
2. Guess it depends on how bad the leak is.
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Post Back. That's whats makes this forum work.

Did it smell like burning oil? Dipstick looks well seated in the pic.

Hey there,

By light of day and with further examination, turns out I have a major coolant leak, so I assume that coolant splashing on manifold was what was causing the white smoke. See my reply to original post for further detail. Meanwhile, the area does also seem a bit "oily," not sure if that's an artifact of coolant leak.