Burned Valve Database DATA ONLY or a P0455 code will be set

[cn90]

Dumb question re burned valve and gas mileage.

If the cylinder #3 Exhaust valve is burned and I already disconnected the connector to injector #3, the piston #3 simply runs up and down the bore w/o contributing to engine power.

For those who drive around with 1 burned valve and injector disconnected, what is your gas mileage?
Same vs worse vs better?

[thebull]

a) Year = 1993
b) Model = 850
c) Mileage Total = 220 000km
d) Mileage under your ownership = 20 000km
e) Octane Gas you typically use = 91
f) Supplier of Gas = Shell
g) Driving Cycle (% city/ % hwy) = 80% city 20% hwy
h) Driving Behaviour (average, passive, aggressive) = average
i) Typical Load in Vehicle: single occupant, or multiple occupant = two people
j) Location and Typical driving weather = -10 C to 37 C
k) Does the car have leaky valve guides (ie: blue smoke at start up) = Oh Yes!
l) What kind of oil do you use - Castrol 5W40
m) Describe in detail how it happened: (ie: ambient temperature, throttle input, load, etc.) = Fresh Oil change and on the hwy.
n) How many valves burned and which Cylinder = 1 valve #3 cylinder
o)What brand coolant do you use, when was it last changed. = Volvo coolant at 204 000km with the timing belt
p) What did you do with engine/car = New head-gasket, lap all the valves (with 3 new exhaust one), new valve guide seals.

I sold this car to friend of mine. Now approaching 300 000km and runs strong. No oil consumption.



Car after

[j-dawg]

I was instructed by my Volvo dealer service to reseat and remove deposits from the valves to run the car in second on the highway rpm at 5000 for five minutes without interruption and ac off.

Then the valves would reseat. It worked like a charm and the car would idle smoothly and start right up cold for a while.

The old-fashioned Italian tune-up! A bottle of Techron in the tank every few thousand miles is probably good prevention, at least for the intake valves.

[E Showell]

My mechanic advises to use Techron sparingly. Suggests you can over do it.

[j-dawg]

Yeah, I've heard rumors of it's effects on oils. Best to use it shortly before an oil change.

[mecheng]

a) Year = 1993
b) Model = 850
c) Mileage Total = 220 000km
d) Mileage under your ownership = 20 000km
e) Octane Gas you typically use = 91
f) Supplier of Gas = Shell
g) Driving Cycle (% city/ % hwy) = 80% city 20% hwy
h) Driving Behaviour (average, passive, aggressive) = average
i) Typical Load in Vehicle: single occupant, or multiple occupant = two people
j) Location and Typical driving weather = -10 C to 37 C
k) Does the car have leaky valve guides (ie: blue smoke at start up) = Oh Yes!
l) What kind of oil do you use - Castrol 5W40
m) Describe in detail how it happened: (ie: ambient temperature, throttle input, load, etc.) = Fresh Oil change and on the hwy.
n) How many valves burned and which Cylinder = 1 valve #3 cylinder
o)What brand coolant do you use, when was it last changed. = Volvo coolant at 204 000km with the timing belt
p) What did you do with engine/car = New head-gasket, lap all the valves (with 3 new exhaust one), new valve guide seals.

I sold this car to friend of mine. Now approaching 300 000km and runs strong. No oil consumption.



Car after

What engine/model?

[mecheng]

Updated Pareto analysis, thanks to all that listed their data. Please try to answer all the questions as it creates a complete picture.

Interesting to note that most failures were with aftermarket coolant as the Volvo coolant has been reportedly designed to reduce hot spots in the engine due to turbo charging. Also interesting to note that none were with aggressive driving owners as the valves apparently rotate over 3000 rpm and therefore may clean the deposits. I occasionally run the car in 3rd gear at highway speed for a minute or two for this very reason!

Need more data to draw conclusions, so keep them coming.

I wanted to add what my Volvo dealer told me when my 1998 V70 was a couple years old and had hard cold morning start problems. Oh it was a 2.3 hpt auto equipped car. It also in conjunction with the hard starts also had rough idle in gear almost like a misfire. Car under full warranty at time Volvo dealer told me 5 cylinders engines have problems with deposit forming on valves and causes seating problem causing the problems I experienced.

I was instructed by my Volvo dealer service to reseat and remove deposits from the valves to run the car in second on the highway rpm at 5000 for five minutes without interruption and ac off.

Then the valves would reseat. It worked like a charm and the car would idle smoothly and start right up cold for a while.

I noticed car needed it every six months or so. I did a lot of one mile trips per day with that car. I would think it would cause extreme heat and pressure incinerate any deposits during those five minutes.

I have done it to every Volvo since as preventive maintenance about every six months and never had a rough idle or hard cold start or any sort of valve trouble. June

Excellent info! Yes I read that on one of the Volvo forums a while back, it might have been this forum or SS. The recommendation was over 3000 rpm. 5000 rpm would probably have a higher chance to spin the valves but you also may cause damage to the engine (bearings specifically). I would not perform it on a hot day or with old oil, and the 5 minutes seems excessive to hold 5000 rpm.
Nonetheless, good info.

[rspi]

Updated Pareto analysis, thanks to all that listed their data. Please try to answer all the questions as it creates a complete picture.

Interesting to note that most failures were with aftermarket coolant as the Volvo coolant has been reportedly designed to reduce hot spots in the engine due to turbo charging. Also interesting to note that none were with aggressive driving owners as the valves apparently rotate over 3000 rpm and therefore may clean the deposits. I occasionally run the car in 3rd gear at highway speed for a minute or two for this very reason!

Need more data to draw conclusions, so keep them coming.

I wanted to add what my Volvo dealer told me when Mt 1998 V70 was a couple years old and had hard morning start problems. Oh it was a 2.3 hpt auto equipped car. It also in conjunction with the hard starts also had rough idle in gear. Car under full warranty at time Volvo dealer told me 5 cylinders engines have problems with deposit forming on valves and causes seating problem causing the problems I experienced.

In order to receive seat the valves to run the car in second on the highway rpm at 5000 for five minutes without interruption and the valves would reseat. I noticed car needed it every six months or so. I have done it to every Volvo since and never had a rough idle or hard cold start or any sort of valve trouble. June

Interesting notes. Hopefully I won't have anything to worry about, because I have all the checks on the list as far as common things NOT associated with burnt valves... I drive more aggressively, engine is over 4k RPM almost daily, I run Zerex G-05 coolant, which seems to be very close in quality and chemistry to Volvo blue coolant, and I only run 93 octane Top Tier fuel, using either Lucas fuel treatment or Techron at least monthly.

Same thing I was doing which I believe prolonged the inevitable.

[rspi]

Robert, I had Alfa Romeo's back in the 70's and the very early ones had no valve
stem seals, I don't really think that is it. It is possible that if the seals are bad,
then also the guide clearances are wide and then the valves don't seat as well
leading to leaks and then burned valves.
They were all NA and they all had Sodium cooled exhaust valves.

Come on man, I doubt that Alfa had an engine built like the B5234 nor did it have 350,000+ miles.

[rspi]

Updated Pareto analysis, thanks to all that listed their data. Please try to answer all the questions as it creates a complete picture.

Interesting to note that most failures were with aftermarket coolant as the Volvo coolant has been reportedly designed to reduce hot spots in the engine due to turbo charging. Also interesting to note that none were with aggressive driving owners as the valves apparently rotate over 3000 rpm and therefore may clean the deposits. I occasionally run the car in 3rd gear at highway speed for a minute or two for this very reason!

Need more data to draw conclusions, so keep them coming.

I wanted to add what my Volvo dealer told me when my 1998 V70 was a couple years old and had hard cold morning start problems. Oh it was a 2.3 hpt auto equipped car. It also in conjunction with the hard starts also had rough idle in gear almost like a misfire. Car under full warranty at time Volvo dealer told me 5 cylinders engines have problems with deposit forming on valves and causes seating problem causing the problems I experienced.

I was instructed by my Volvo dealer service to reseat and remove deposits from the valves to run the car in second on the highway rpm at 5000 for five minutes without interruption and ac off.

Then the valves would reseat. It worked like a charm and the car would idle smoothly and start right up cold for a while.

I noticed car needed it every six months or so. I did a lot of one mile trips per day with that car. I would think it would cause extreme heat and pressure incinerate any deposits during those five minutes.

I have done it to every Volvo since as preventive maintenance about every six months and never had a rough idle or hard cold start or any sort of valve trouble. June

I assume that you are stating that you have never experienced a burnt valve in any of your vehicles. I do aggressive runs a few times per week but nothing like 5000 RPM for over 1 minute at a time.

Do you mind me asking what kind of high mileage have you experienced?