I did a brake job on my Grand Marquis today, and took the car out on an open road to bed the new pads. I did several runs up to 100 km/h (63 MPH), braking right down to 20 km/h (13 MPH) without stopping the vehicle and accelerating back up to 100 km/h. I did this about 10-12 times until the brakes got to a point where they started to fade.
After running the car hard, I noticed a cloud of black smoke in the rearview mirror during acceleration. So I stopped the car, and revved the engine in neutral. With each press of the gas, huge clouds of black smoke were coming from the driver's side tail pipe. I reckon it may have been the same on the passenger side as well, although I did notice blue smoke coming from the passenger side. When I killed the ignition, I also noticed blueish smoke coming out the passenger side tail pipe (engine off). This lasted about a minute.
Now the crazy thing is, the car is not an oil burner. During my last run of Liqui-Moly TopTec 4200 5w30, I never had to add a drop of oil during the 6,250 mile drain interval. The engine did use a bit of oil, but it was barely noticeable on the dipstick and probably around 200 ml tops. I have exactly 2,233 km (1,395 miles) on the current fill (Liqui-Moly Synthoil Longtime 0W-30) and the oil level hasn't dropped at all.
Worth noting, however, the car was an oil burner when I bought it because of a problem with the valve seals. So the insides of the exhaust, especially the passenger side, are caked in carbonized oil. I use a mixture of 50 ml TCW3 to 150 ml MMO with the fuel, and ever since I've noticed the deposits in the tailpipe getting less to the extent where I can now see the shiny metal underneath all the oily carbon. The driver's side is extremely clean, but the passenger tailpipe puffing blue smoke is still dirty. So my guess is the additive is increasing combustion temperatures, and the blueish smoke I saw could have been because of the oily deposits in the tailpipes.
Getting back on topic, after letting the car sit and allowing it to cool down, there is no smoke from the exhaust at all. But run it hard enough, and it will puff out black smoke under load. When you run it hard for a period of time, the engine also starts to ping under load. My guess is the EGR valve, and I am considering replacing it rather than cleaning it, considering it's the original with 252,100 km (157,563 miles) on it, but I just wanted to hear what better qualified BITOGers have to say.
Thanks!
After running the car hard, I noticed a cloud of black smoke in the rearview mirror during acceleration. So I stopped the car, and revved the engine in neutral. With each press of the gas, huge clouds of black smoke were coming from the driver's side tail pipe. I reckon it may have been the same on the passenger side as well, although I did notice blue smoke coming from the passenger side. When I killed the ignition, I also noticed blueish smoke coming out the passenger side tail pipe (engine off). This lasted about a minute.
Now the crazy thing is, the car is not an oil burner. During my last run of Liqui-Moly TopTec 4200 5w30, I never had to add a drop of oil during the 6,250 mile drain interval. The engine did use a bit of oil, but it was barely noticeable on the dipstick and probably around 200 ml tops. I have exactly 2,233 km (1,395 miles) on the current fill (Liqui-Moly Synthoil Longtime 0W-30) and the oil level hasn't dropped at all.
Worth noting, however, the car was an oil burner when I bought it because of a problem with the valve seals. So the insides of the exhaust, especially the passenger side, are caked in carbonized oil. I use a mixture of 50 ml TCW3 to 150 ml MMO with the fuel, and ever since I've noticed the deposits in the tailpipe getting less to the extent where I can now see the shiny metal underneath all the oily carbon. The driver's side is extremely clean, but the passenger tailpipe puffing blue smoke is still dirty. So my guess is the additive is increasing combustion temperatures, and the blueish smoke I saw could have been because of the oily deposits in the tailpipes.
Getting back on topic, after letting the car sit and allowing it to cool down, there is no smoke from the exhaust at all. But run it hard enough, and it will puff out black smoke under load. When you run it hard for a period of time, the engine also starts to ping under load. My guess is the EGR valve, and I am considering replacing it rather than cleaning it, considering it's the original with 252,100 km (157,563 miles) on it, but I just wanted to hear what better qualified BITOGers have to say.
