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Coolant Leak

About three weeks ago my car started rapidly leaking coolant. Since then I have been using mostly water to keep my car cool because I do not have the money to fix it right now. Then a few days ago I started having trouble getting my car started and today it died while it was idling. Could the water have caused all of these problems in such a short amount of time?

You didn’t mention where the system is leaking. An external leak should not affect engine performance, as long as you keep the coolant level high enough to prevent overheating. An internal leak could cause problems. Sometimes internal leaks in the water jacket or at the head gasket will allow coolant to enter the combustion chamber(s). One quick check is to look at the oil on the dipstick. If it looks milky, you’ve got water in the oil. In this case the coolant has probably entered the combustion chamber and made its way into the oil pan. Another symptom is steam coming out of the tail pipe when the engine is running.

I should have added that water by itself is no more likely to cause trouble than coolant, by which I mean an antifreeze-water mixture. It may be that your other problems are unrelated to the coolant leak. You’ve got to determine where the coolant is leaking and whether it is entering the combustion chamber.

Please provide the following:

Make: _______________
Model: _______________
Year: ________________
Miles: ________________
Engine (if known):___________
Transmission (automatic or Manual):__________

What are your outside temperatures like? Is it getting below freezing where you operate this car?

Straight water (no antifreeze/antiboil) will boil and create steam at lower temperature than the proper mix. This is exactly what you don’t want if you have a leak. One who cannot afford antifreeze cannot afford to drive. Now you have the problem of not being able to drive and possibly more damage to your car than you had when it just leaked, but ran.

“Could the water have caused all of these problems in such a short amount of time?”

Yes.

I wonder if junkyards ever have used coolant available from the cars that come in. That might be better than straight water.

Water is not a great coolant. It will not work as efficiently as the coolant/water mix specified. It also will not protect you from freeze damage.

Depending on where the coolant is going, driving it even with real coolant could cause expensive damage to the engine.

My advice is if it needs more than a gallon total (all additions since you noticed the problem, then you are not at risk for serious damage.

Unless you can afford to replace the car today, you can’t afford to rive it.