will highway driving clean engine?

[WmWatt]

Well, the car passed the emissions test fine.

HCppm limit 95 reading 21, and limit 200 reading 61 at idle
CO% limit 0.54 reading 0.01, and limit 1.00 reading 0.14 at idle
NOpmm limit 1123 reading 121, and N/A at idle

The car has 116k km with original O2 sensor and catalytic converter

I forgot to mention I sprayed carburettor cleaner into the carburettor as part of the preparatory minor tuneup. I do this once a year.

As for the foam under the valve cover, it has been there once before years ago and I was advised to take the car out for a run on the highway. That got rid of it. I did take it fro a short run (Bert: to Manotick) but got distracted by an impromtu visit to the new HQ of the conservatrion authority so the engine was not continuously running. Also it was only 25 miles 'round trip. I expect the foam to burn off soon with longer seasonal driving.

Thanks for all the advice.

[blkfordsedan]

I have the same problem with every car my wife drives. She only drives about 1 mile to work every day and never gives the car time to warm up. I try to start her car in the AM and let it warm up to operating temp when I can, but it does little good. Frequent oil changes are the only way to combat in such situation.

Also, rust in the exhaust system is accellerated as well. I've always said that I would buy a car with 100+K highway miles over one with 50K all city miles any day. Think of how many times the trans shifts, brakes are applied, steering wheels are turned, doors opened, etc. when the mileage is all "in town".

[nonamekid]

To me, foam in the PCV and valve covers means blown head gasket and you're getting coolant in the oil...

That is the case some of the time. That typically presents itself with other issues also though, ie: pressurized coolant system, overfull oil, lack of power, and/or excessive exhaust. With no other symptoms, cool weather and short trips is the likely reason. Short trips in the summer tend not to get this issue as much as short trips in the winter. This is typically not an issue if the car is driven for about an hour, and then all the moisture should be gone.

[Movin]

To me, foam in the PCV and valve covers means blown head gasket and you're getting coolant in the oil, which will destroy an engine. When oil and coolant mix is makes the oil very foamy/sudsy and runny effectively making it too thin to work properly. With the lack of coolant and contaminated oil an engine will overheat and blow real quick.

I would check the coolant level before heading out next time. If it is good then hopefully this isn't the case but I've seen several cars die from this. (Mostly people not letting their cars warm up in winter causing a blown head gasket..idiots..)

But for general cleaning, I'd use a good ol' can of SeaFoam. 1/3 in oil, 1/3 in tank, 1/3 sucked into vac intake line off Brake Booster. Have a friend rev the engine till it's all sucked up, let it sit 10-15 mins, keep engine up at high revs till smoke clears. Then I'd change the oil shortly after some normal driving.

I brought my wife's 84 Honda back from the grave with a single can of SeaFoam, its great stuff! It would take 45 sec of continuous cranking to fire up and would die if you let off the gas. After 1 can of SF it started right up 1-3 cranks for years till the water pump died and we sold it. It is still driving around today with near 400k on it

Sorry I'm a bit of a wind bag sometimes lol

This is the best way to use any injector cleaner outside of Pro cleaning systems. Heck use two or more cans, cleaner is better. Can even clean
up a cat some. Excellent advise and good instruction!!!