Car ATF fluid sucked by Car engine, what to do ??

Question

Car mechanic topped up ATF fluid in my auto car, engine noise changed with large cloudy fumes from the exhaust pipe. It seems my car engine sucking ATF fluid, what harmful effects it can have on the car engine health ?? I only drove for 2.5 miles before stopping.

Thank YOU very much to people who so far have answered the question.
More details:
Car is a Renault Clio 1.4 Automatic Year May 1996.

Answer 1

I've actually had this problem on at least two different vehicles. From what you are describing, it sounds like the shift modulator is faulty. The shift modulator is a device attached to the transmission (it will be in different locations, depending on make and model of car). What happens is that the shift modulator is vacuum actuated and over time the rubber diaphragm bursts inside and then the vacuum line sucks transmission fluid through the intake (either your intake manifold or carburetor) and then burns in the combustion process. It makes a huge cloud of smoke and really stinks. The part will probably cost around $12 and it might take about 15 minutes to swap it out. One way to verify is to take the vacuum line off the shift modulator and if there is any fluid in the vacuum line it is definitely the problem, however you may not see any fluid so that is not a sure-fire way. There was one that I just had to accept on faith that was the problem and when I swapped the part out it fixed it. Good luck and I hope this fixes the problem.

Answer 2

It won't destroy your car, however it will foul up the spark plugs if left in it's present state. The main question is ''How did the ATF fluid get from the transmission to the intake manifold?''. Older cars had on their automatics a device called a ''modulator''. It's purpose was to control shifting of the gears. Inside the modulator there was a rubber diaphragm. When this Daphna cracked, the transmission fluid would get sucked into the intake manifold via a vacuum line connected to the modulator. Perhaps this or something similar is the problem.

Answer 3

As long as it is not sucking in too much, there will be no harm. We actually used to do this on purpose to try to de-carbonize motors back in the old days. If the motor sucks in too much at once; however, serious motor damage can occur such as bent connecting rods or a hole in the piston. Obviously the motor is not supposed to be supplied a constant amount of any type of lubricant to be burnt. You need to have the leak of ATF fixed right away. It is usually drawn into the motor from the vacuum modulator that is mounted on the trans. case. If this diaphram is leaking a small amount, it will draw the fluid through it up into the motor through the vacuum supply line down to it. As you have not stated what type of car or transmission is in service here, that is about all I can tell you about this.

Answer 4

Bad vacuum modulator on the transmission. There's a vacuum hose going to it from the engine and when the modulator seal goes the engine vacuum draws transmission fluid into the intake manifold. You can disconnect and plug the vacuum hose and the engine port it came off of for a while. It won't shift very well, but it will get you through the day till you get it fixed.

Answer 5

You failed to mention what KIND of car. BUT...LOL..alot of cars....GM made a bunch like this.....have an automatic transmission that shifts using the engine vacuum. This " Vacuum Modulator" is located on the transmission and has a vacuum line directly to the intake manifold. When the " diaphram" goes bad...it sucks the fluid out of the transmission...up the line...into the engine and burned where it makes alot of smoke. Get it fixed...shouldn't be a big deal.

Answer 6

Transmission fluid chambers and combustion chambers are so far apart that that's not possible.

Large clouds of white fumes typically means you're burning coolant. Typically because of a head gasket leak, cracked head or cracked block and radiator fluid is getting into the combustion chamber.

Have your engine cylinders leak tested. to determine if the head gasket has gone bad, or check to see if you have water in your oil or oil in your radiator (a sure sign that the head gasket has blown)

Unless your mechanic poured ATF fluid into the crank case and the less viscous fluid is getting past the oil rings to be burned, the transmission fluid and engine combustion chamber don't interact.

Answer 7

Yes it has fluid. At least it better have. There is a plug about halfway up on the side of the transmission. The fluid level should be even with the bottom of the hole. Don't remove the plug that is on the very bottom on the side, this will drain your fluid. Your truck most likely has a Warner 77mm 5 speed (T5). If so it requires Dexron-II fluid, not gear oil.

Answer 8

I, as many others, wonder what kind of car you are driving???????????????The VACUUM operated MODULATOR on the back of your transmission has died. The internal diaphragm of the modulator has ruptured.This will do no harm to the engine but it will, in short order, contaminate your catalytic converter. No fault of the mechanic,,,,Just have replace the transmission modulator. Take it for a long high speed ride to try to clean out the converter. At least 100 miles at highway speed.

Answer 9

It won't hurt if that's what it is. It used to be a common practice to drip ATF into a carbureator while the engine was running to help clean the carbon off of the valves. Does it work. Ask the NASCAR guys, some of them still swear by it to this day.

Answer 10

Sounds like a older car with a vacumm shift modgulater < spelled wrong< what happens is when this past goes bad the vacumm it uses to make the trans shift is sucked into the motor