Hi,
Just wondering if anyone can suggest anything further about an issue on which I've asked for advice in this group. Here is the problem. Due to a lapse in my own oil-checking diligence, I burned my engine out. My mechanic changed it for a used engine, not remanufactured. The replacement engine had no oil films to prevent rust, etc.. The work took place over 5 days at the beginning of January (cold winter outside, in case that matters). When I got the car back, I smelled all sorts of smells, and noxious fumes that caused my eyes to water and coughing that lasted 1-2 days after driving. Smells include (subjectively):
- Burning oil or diesel-like smell * Hot oil (smouldering?), not as bad as burning * Burning rubber * Musty, dusty sensation more than a smell, most associated with the lung/eye aggravation
There were black fumes coming out the exhaust upon starting. The valve seals were changed, which greatly mitigated the burning oil smell and eliminated the black smoke from the exhaust. The hot oil smell and caustic fumes persisted. Here were some things checked:
- No cross contamination between coolant and oil * No damp spots in the heater to suggest a pin-hole leak * No critters or feces up in the heater fan/core * Air ducts blown out with shop air * No fluid level decreased except for engine oil * Exhaust was system was checked (plugged at the rear to check for leaks) * Exhaust was analyzed (not sure what that involves) * Sensors where checked (I think that's what he meant by teradyne) * Cylinder pressure checked * Leak-down tests were good * Engine was shampooed * Aggravating fumes start to come in about 15-20 minutes after starting in winter (-10C or +14F), about 5-10 minutes now (+10C or +50F) * PCV was OK * Grommet between engine & passenger compartments good * A 2nd mechanic confirmed cylinder pressure, grommet, & PCV OK * I changed the PCV valve anyway (running out of ideas) * Visual inspection of firewall and hood gasket by person from Krown rust control
The decrease in oil was due to a leak where the crank shaft enters the transmission. I am at a loss as to why this was not caught after a few visits. I found it by crawling under the car, which is kind of tricky considering that I don't have ready access to my ramps (my apartment's locker policy is to only allow access at 10:30am, my place is too small to store them in the apartment itself). I'm mentioning this because it is something I have to be careful about -- I have to access the thoroughness of my mechanic rather than dismissing some possible causes because he didn't find any indicators. I've been bringing my car to him for a long time, and I think he is ethical and competent (and goes way out of his way to make accommodations). But I cannot understand how such a big leak could have been missed, and that simply affects how I go about troubleshooting.
Regardless, the oil stopped leaking after the seal was replaced. He also replaced the gasket where the front pipe meets the exhaust manifold, in case that was the cause (he thought it prudent when he noticed some soot around the old gasket). He prophetically said that he didn't think that was the cause of the caustic fumes -- something which makes sense, since the fumes did not smell like exhaust. Along these lines, a body shop manager at a Toyota dealership said that the car had no rust or perforations that might cause exhaust to be drawn in from the back.
Somethings which seemed to help for less than day (might just be wishful thinking) are:
- Driving through a touchless car wash with undercarriage spray * Pooring pails of warm water into the ventilation intake grill beneath the wipers * Aiming pressurized spray down the vent intake grill for 3 minutes * Having a detailing place shampoo the engine compartment
All of these washings reduced the smell. The last item practically eliminated all smells, including the chemical smell from my mechanic's shampoo. None of these washings seemed to have helped with the caustic fumes beyond a few hours, if at all.
I noticed on more than one occassion that when speeding up or down shifting, I get a whif of that dusty/musty smell associated with the caustic fumes at the top of the 1st or 2nd gears (when the engine revs are high). Based on my own rather naive understanding of things suggested in this group, it seems to indicate a head gasket problem, and a pin-hole leak in the heater core. That is, when the engine is reving high, maybe there is more pressure leaking to the cooling system, thus aggravating a pin-hole leak in the heating core. I realize that there are many counter-indications, such as the lack of cross contamination between oil & coolant, good results from leak- down test, and the lack of damp spots on the heater core. About the last point, however, I'm not sure if such a pin-hole leak would show except at high revs. I asked my mechanic to try a test suggested here: connect the intake and exit hoses to the heater core so that the coolant bypasses the heater core, and empty the coolant out of the heater core. He said that has the same effect as turning the air temperature to cold, but I suggested that there may be a difference, since the heater core is not empty of coolant when the air temperature is set to cold. He has agreed to do this, but his only opening is in about 2 weeks. I will drive with the windows down until then (hope it doesn't rain much). If that gets to be too long, I'll bring it somewhere that can do it sooner.
This testing for a leak in the heater core only a shot in the dark, in the absence of any other possible debugging ideas, and especially considering the counterindicators. Can anyone suggest any other course of action?
Tercel Owner
P.S. The oil level dropped from 110% to 80% in the last 2 weeks. I take 100% to mean the full range from "full" to "low". So 100% is at the full mark, 110% means that last oil top-off was 10% over the full mark. I thought all gross causes of oil consumption were eliminated by replacing the valve seals and stoping the leak where the crankshaft enters the transmission, but I wonder if a 30% drop in 2 weeks is normal?