Why Won't My Car Start?
If you turn your car key and get nothing, or get anything less than an engine roaring to life, you might be in for a bad day. Starting problems can be very frustrating because there are so many things under the hood that can keep a car from starting. Heck, pretty much everything under the hood can keep the car from starting.
In order to troubleshoot a no-start problem, you need to start at the beginning of the line, the battery, and work your way back. Some tests for a no-start problem are simple, others are a pain in the neck and a technical nightmare. Nonetheless, you need to figure out why the car won't start, so we'll try to help. If your key won't turn in the ignition, try this fix.
Electrical No-Start Problems
• Check Your Fuses: Few cars have a fuse associated with the starting system, but before you go monkeying around with everything, check your fuses to be sure it's not that simple.
• Battery Corrosion: Over time your battery connections can become dirty, or corroded. This corrosion breaks the connection your battery has with the rest of the car, and it won't start. Try cleaning your battery posts and try to start the car again.
• Dead Battery: The most common reason your car won't start is a dead battery. If you have a battery tester that can measure cranking amps, test your battery to see if it's weak. If you can't test it yourself, you can test the battery indirectly by jump-starting the car. If it starts right away, your problem is most likely a dead battery. Replace the battery, and clean the battery connections to ensure good contact.
• Bad Igntion Switch: If your battery checks out, but the starter is still silent, it may be a faulty ignition switch. Turn the key to the on position (not all the way to start). If the red warning lights on your dash don't light up (and your battery connections are clean), the ignition switch is bad. If they do light up, turn the key to the start position. The dash warning lights should turn off at this key position (most cars). If you're not sure, turn on the headlights. When you try to start the car, the lights should either dim (a lot) or turn off completely. If they do, your ignition switch should be ok. If not, the switch will need replacement.
• Bad Starter Connection: Corrosion can not only keep your battery from connecting, it can affect any electrical component, especially the ones exposed to the elements like the starter. If you have a helper, you can test the connection by holding a circuit tester lead on the wire that engages the starter. This is the smaller of the two wires connected to the starter. Be sure no part of your body is near the moving parts of the engine - it could still start at any time! Have a friend turn the key and check the current. If you're getting current to the starter but it ain't spinning, it needs replacement.
If your starter spins freely when you turn the key, the problem lies elsewhere. Now you begin to check the other systems that could keep it from firing up.
Diagnose Automatic Transmission Problems
There are a few words in the language of auto repair that make car owners want to crawl back into bed, and "transmission" is at the top of the list. There's something about that mysterious box underneath your car that incites fear. Unfortunately, most repair shops know this, and will take advantage of the situation by reaching deep into your pocket.
Before you hand over your keys and a blank check, brush up on the simple end of automatic transmissions. If something is seriously wrong, at least you'll be armed with enough knowledge to avoid being overcharged, over-repaired or straight ripped off. Sometimes it's easy to diagnose automatic transmission problems.
Your transmission is a remarkable contraption. Somehow it can shift your car from gear to gear, knowing how fast you need to go and how quickly you need to get there. What goes on inside is a mystery to most. Unless your thirst for automotive knowledge borders on compulsive, you can leave it a mystery. The basics will be enough to have an intelligent (which translates to "not about to be ripped off") conversation with your mechanic.
Basic Parts of a Transmission
While there are many, many little parts inside, your transmission is essentially made up of a few key parts of systems.
• Bell Housing: This is the cone shaped metal case that you can see when you peek underneath your car. If you have a front-wheel-drive car it's stuck on the side of the engine under the hood. If your car is rear-wheel-drive, the tranmission will be mounted underneath the car behind the engine.
• Gears: Even though you're not shifting them, an automatic transmission has gears. They are broken into main gears and planetary gears. You need all of these to be able to drive.
• Fluid: Transmission fluid is very important to an automatic transmission. All of the magic happens in the fluid. Most cars come with red transmission fluid, good to know if you are looking for a leak.
• Filter: All of that fluid has to be clean for your car to shift gears at the right time. To keep things fresh, your transmission has a filter to catch any gunk.
Now that you know a little about what's happening in there, you can try to figure out why your transmission is acting up, or at least understand what your mechanic is talking about while he tries to make your bill into his new fishing boat.
Transmission problems fall into two very similar categories:
• Won't go.
• Won't go smoothly
These two groups of problems are caused by the same faults in your transmission, so whichever your car is doing, the following applies.
Is your fluid level correct?
It's important to check your transmission fluid at least twice a year. Not only can a low fluid level cause your car to shift poorly, it can eventually lead to transmission damage, and a costly repair. If your car seems to be losing fluid on a regular basis, you may have a leak.
Is your transmission leaking?
Checking for leaks isn't as trying as it may seem. The transmission is a closed system, so there are only a few places that can spring a leak. Unless it's been changed to a non-dyed fluid, your car will have red transmission fluid. Here are a few places to check for leaks:
• At the filler tube base.
• At the drain hole underneath the transmission.
• Between the transmission and the engine.
• At the selector shaft - the rod that connects your gear shift to the transmission.
• Speed sensor mounting point. This will either be your cable screwing into the transmission housing or an electronic sensor bolted to the housing.
• The radiator. If your car has a transmission cooler, it's possible that a leak will cause transmission fluid to leak into the radiator fluid. They don't mix well, so you'll see it floating around in there.
Is your filter clogged?
Your transmission's filter is vital to its performance. If you haven't replaced your filter in a while (or ever for a lot of us), be sure to do this before you start talking about rebuilds or replacements.
Most transmission problems can't be fixed by the average do-it-yourselfer. There are just too many specialized tools and pieces of equipment you'll need, and buying this expensive gear just to screw up your first three tries at fixing the thing just doesn't make too much sense.
Now that you're in front of the firing squad, it's time to drop some knowledge on your fix-it guy. Tell him what the car's doing. Then tell him what you found out when you inspected the transmission. If there's a leak, let him know where and how much is leaking.
Time for a rebuild?
When your transmission gets tired enough, you'll have to have it rebuilt. It's true. For some makes and models of car, it's true a little too often, but that's neither here nor there. The important thing is checking any other possible causes to your problem before you take the transmission apart, which is very expensive. If you haven't replaced your filter yet, do it! This fixes a nice percentage of transmission problems. If your filter is good, and nothing simple is out of adjustment, be prepared to drop some serious dough on the rebuild. The good news is that most shops warrantee a transmission rebuild for a nice amount of time. A small consolation as your handing over the credit card, but at least you know that it will get fixed and stay fixed.
on Dec 29, 2009 | Volkswagen Euro Cars & Trucks