Ok. my car 97 pontiac sunfire needed a new alternator output cable. guy put a new one on but apparently messed with something else and now its not starting. said the theft light came on and that it isnt getting a spark. he has had it for a week and it still isn't starting what do i do?

Need alternator output tested at idleand at 2,000 RPM for both current and voltage . Post results .

Have you checked alternator output on the car, and will the battery stay up if you disconnect the cables overnight ?

Your car's symptoms (voltage fluctuations under load that shouldn't happen) seem to
strongly indicate that your voltage regulator has failed. The voltage regulator is the component
that regulates voltage coming from the alternator, and which is supplied to the rest of the car.
Your new belt tensioner indicates to me (and should have to your mechanic) that the
alternator and/or voltage regulator weren't able to operate properly, and a faulty belt tensioner
has killed more than one car's alternator/voltage regulator.
Your do not need new headlights. Do fix the turn signals.

In the 2005 Sunfire, the voltage regulator is an integral component of the alternator, and is
not separately serviceable. So your 2005 Sunfire needs a new alternator.

2005 Pontiac Sunfire Alternator - Duralast Part Number: DL2305-15-4 $199.99 available at:
http://www.autozone.com/autozone/parts/2005-Pontiac-Sunfire/Alternator/_/N-jmqtpZ93xme

The national parts chains (Advance Auto Parts, AutoZone, Pep Boys) will (for free) administer
a "Charging System Test." Which will telly you for sure that your alternator/voltage regulator
is bad. Do this before replacing alternator, since its a pricy part in the 05 Sunfire.

Just in case, Here's the 2005 Sunfire manual entry on (a) Diagnosis & testing the alternator, and
(b) replacement of the alternator

Alternator replacement is a do-it-yourself project, though you may need to get a
"Serpentine Belt Kit" on your favorite parts store's loan-a-tool program to remove/re-install the serpentine (drive) belt.
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Diagnosis & Testing - 2005 Pontiac Sunfire Alternator


Alternator Load Test

1. With the engine running, turn on the blower motor and the high beams ( or other electrical accessories to place a load on the charging system).

2. Increase and hold engine speed to 2000 rpm.

3. Measure the voltage reading at the battery.

4. The voltage should increase at least 0.5 volts from the voltage test. If the voltage does not meet specifications, the charging system is malfunctioning.
NOTE
Usually under and overcharging is caused by a defective alternator, or its related parts (voltage regulator), and replacement will fix the problem; however, faulty wiring and other problems can cause the charging system to malfunction. Many automotive parts stores have alternator bench testers available for use by customers. An alternator bench test is the most definitive way to determine the condition of your alternator.




Alternator No-Load Test

1. Connect a tachometer to the engine.
CAUTION
Ensure that the transmission is in Park and the emergency brake is set. Blocking a wheel is optional and an added safety measure.


2. Turn off all electrical loads (radio, blower motor, wipers, etc.)

3. Start the engine and increase engine speed to approximately 1500 rpm.

4. Measure the voltage reading at the battery with the engine holding a steady 1500 rpm. Voltage should have raised at least 0.5 volts, but no more than 2.5 volts.

5. If the voltage does not go up more than 0.5 volts, the alternator is not charging. If the voltage goes up more than 2.5 volts, the alternator is overcharging.
NOTE
Usually under and overcharging is caused by a defective alternator, or its related parts (regulator), and replacement will fix the problem; however, faulty wiring and other problems can cause the charging system to malfunction. Many automotive parts stores have alternator bench testers available for use by customers. An alternator bench test is the most definitive way to determine the condition of your alternator.


6. If the voltage is within specifications, proceed to the next test.



Voltage Test

1. Make sure the engine is OFF , and turn the headlights on for 15-20 seconds to remove any surface charge from the battery.

2. Using a DVOM set to volts DC, probe across the battery terminals.

3. Measure the battery voltage.

4. Write down the voltage reading and proceed to the next test.



Removal & Installation - 2005 Pontiac Sunfire Alternator


2.2L (VIN 4) Engines

1. Before servicing the vehicle, refer to the precautions section.

2. Remove or disconnect the following:

Negative battery cable

Accessory drive belt

Alternator mounting bolts

Alternator electrical connectors

Alternator





To install:

1. Before servicing the vehicle, refer to the precautions section.

Alternator. Torque the upper bolts to 37 ft. lbs. (50 Nm) and the lower bolt to 22 ft. lbs. (30 Nm).

Alternator electrical connectors

Accessory drive belt

Negative battery cable





2.2L (VIN F) Engines

1. Before servicing the vehicle, refer to the precautions section.

2. Remove or disconnect the following:

Negative battery cable

Accessory drive belt

Alternator mounting bolts

Alternator electrical connectors

Alternator





To install:

1. Install or connect the following:

Alternator. Torque the bolts to 16 ft. lbs. (22 Nm).

Alternator electrical connectors

Accessory drive belt

Negative battery cable

Alternator

Sounds like the alternator is on its way out. It should have roughly the same voltage output all the time.

you should take it somewhere llike a local parts store to have them test chargeing system and battery for free.Alot of them do that now days.

try checking the coolant resivoir level sensor has not come loose or got a bad conections in the plug.

Have your battery charged and load tested to make sure it's OK. Then check the charging system and alternator drive belt for tension and condition. If car won't staqrt after charge, you may need to remove alternator to have it tested on a bench. Otherwise, put a volt meter across both terminals. With engine off, volts should be 12 or higher. Running should be 13,5-14V running with all lights, heater and A?C on should not drop lower than 12.8v.Low readings running indicate a bad alternator. If everything in charging system checks out OK, problem is likely in the starter or starter relay.

If your timing is off you will have no power.check and make sure all timing mark's are correct.Some engine's are contact motor's,which mean's if your timing is off you could cause damage to valve's or piston's.Also you should do a compression test to be sure each cylinder has adequite pressure.Hope this help's.

please email me at [email protected] with any other info or questions i need more info