If your Fiero seems to be turning over slowly I would suggest the following
steps (not necessarily in order of likelihood, but rather ease of checking):
| Use a good voltmeter to check the battery voltage. Voltage should go up
with the engine running about 2000 rpm. |
| Check the battery water level (I cover the battery with a towel when I
pop the caps to catch any acid that may spray). |
| Remove and clean the battery terminals and cables with a wire brush.
After reassembly, coat with grease or vaseline to prevent corrosion.
(Be careful to never hit the wrench to metal). |
| Check the positive battery cable to starter connection. This was the
source of all my problems. As you have to work near the exhaust, wait
until the car cools. Disconnect the battery cables, as otherwise it will
be an electrical disaster if you hit any metal with the wrench while
tightening this connection. It took a 15 mm wrench, putting the car up
on blocks, and some arm contortion to get it tightened. |
There are two likely causes of this. One is a fuel delivery problem,
and the other is an ignition problem.
| Turn the key to the run position. Do you hear the fuel pump run for a
second or two? Note that it does not do it EVERY time you turn on the key,
just when it's been several seconds or more, and the fuel system needs to be
repressurized.
| If you don't hear it, you need to check your fuel pump relay. |
| If you do hear it, the fuel pump is probably not your problem. |
|
| Check for firing injectors. On the four-cylinder, this is simple. Take
off the air cleaner and you can see the injector spray fuel. It should spray
a nice conical shape. On the V6, you can't see the injectors, but if you have
a voltmeter, you can test whether they are being fired. This won't necessrily
eliminate them, but it is unlikely that all of your injectors would go bad at
once. Unless you got something bad in your gas, or you are out. (You DID
make sure you're not out, and that it's not your gas gauge which is bad,
right?)
| To test whether the ECM is firing the injectors, disconnect the large
flat six-connector wiring harness located near the passenger side of the rear
(closest to the trunk) valve cover. Each set of two pins can be tested with a
voltmeter. The first two power three of the injectors. The middle two fire
the other three injectors.
The last two fire the cold start injector (only fired during cranking, when
the engine is cold). |
| If they aren't firing, you have a wiring problem or an ECM problem. Don't
forget to check the fuses. There are two, one for each bank of injectors. |
|
| If you didn't find anything wrong with the fuel system it's time to
check the ignition system. The easiest thing to do, is to take off the
distributor cap (don't disconnect the plug wires) and look at the
metal contacts on the inside. If they are
covered with corrosion (flaky white stuff), then take a screwdriver and scrape
it off. Note that if it is very corroded, it may mean the contacts are too
worn and need replacing. If your cap needs replacing, your wires probably do
too. But you can test a few other things for free, before you spend the
$20-$30 for a new cap, rotor, and set of wires. |
| One of the most common causes of ignition problems on the Fiero is the
ignition module. Many parts stores will test it for free, or you can buy a
$30 tester that will do it for you. |
| If you don't have anywhere handy that will test it for free, disconnect
the wire leading from the coil, at the distributor. Set it so that it is
next to something metal, like one of the nuts on top of the strut tower. Have
someone crank the car, while you watch (not too closely!). You should see an
arc of electricity from the wire to the metal. If not, your coil is not
firing. This means either your coil is bad, or your ignition module is bad. |
| If it did arc, then check the individual spark plug wires in the same way.
You should see a nice blue arc every time. If you get a good spark on some
wires, and not on others, replace the wires. Then re-test. If you get the
same results, replace the distributor cap and rotor. |
| If the hold-down bolt on the distributor is missing or if you have removed
the distributor, it may have become turned enough so that the timing is too far
off to start the car. You will have to set the timing to fix it. If the
distributor was removed, you may have to re-time the engine. |