The car drive fine without using air conditioning but lost power when turning the air cond....have to press the petrol/ pedal or the engine will die...

1. Replace any hydraulic line showing external damage. Rubber hoses more than 4 years old should be replaced. Install new seals for all disconnected fittings (as required) and install an in-line power steering filter. Tighten all hose fittings to OE specifications. 2. Flush the entire power steering system using the vehicle manufacturers recommended fluid. Fill pump reservoir to the proper level.
3. Disable engine to allow cranking without starting. This can be done by unplugging the main power wire (large red one) from your Delco HEI Distributor unit. Block wheels, put transmission in neutral or park and set parking brake, then crank engine 5 to 10 seconds (avoid overheating starter motor).
4. Refill pump reservoir as necessary. Repeat step 3 until level is correct.
5. Enable the engine to allow starting. Start engine and let idle. Slowly turn steering wheel from lock to lock a number of times.
6. Turn engine off and inspect fluid level and condition. Add or remove fluid as necessary. If fluid is foaming, wait one hour then recheck level. Repeat step 5 and 6 until fluid level is correct and shows no sign of air. If the problem persists recheck installation and connections.
1. With engine off, apply and release brake pedal 5 to 10 applications to deplete accumulator reserve pressure. With foot slightly pressing brake pedal, start engine. Pedal should drop and then push back against your foot.
2. With engine running, turn steering wheel until lightly against steering stop. After 5 seconds return wheels to the straight ahead position and turn engine off. Apply and release brake pedal. There should be at least one power assisted brake application. Start engine and allow accumulator to recharge before moving vehicle. 3. Test drive vehicle.
NEVER operate any vehicle until brake and booster systems are functioning properly. Remember, your vehicle is only as good as it's braking system. Brakes are the singlemost important component on any motorized vehicle.

Bleed fuel system you probably have air in system...check file pressure /volume from fuel pump discharge line look on the net

Throttle Actuator Control (TAC) System Description
You have APP- accelerator pedal position sensors or one of the Throttle position sensors is going bad ! In the (TAC) system ! This is drive by wire or electronic throttle control . If you take it to the dealer or a ASE certified repair shop they can check the DTC'S - diagnostic trouble codes ! This is nothing for a DIYer to mess with ! This system can set 7 different DTC'S

Reduced Engine Power Mode When the PCM detects a condition with the TAC system, the PCM may enter a reduced engine power mode. Reduced engine power may cause one or more of the following conditions:
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Acceleration limiting--The control module will continue to use the accelerator pedal for throttle control; however, the vehicle acceleration is limited.

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Limited throttle mode--The control module will continue to use the accelerator pedal for throttle control; however, the maximum throttle opening is limited.

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Throttle default mode--The control module will turn off the throttle actuator motor and the throttle will return to the spring loaded default position.

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Forced idle mode--The control module will perform the following actions:

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Limit engine speed to idle by positioning throttle position, or by controlling fuel and spark if throttle is turned off.

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Ignore accelerator pedal input.

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Engine shutdown mode--The control module will disable fuel and de-energize the throttle actuator.


Drive by Wire Function and Diagnostics by Wells

this sounds like a problem with the throtal pot located on the end of accelorator pedel thi used to be a problem

I would have someone check the computer for trouble codes next.

The fan fuse was blown? Well, the only way that will make your engine overheat is if you were sitting still for a long time and it overheated. If you keep the vehicle moving, the air can cool the radiator (without the fan), and it should be fine.

Even I had this problem. After sometime engaging gear was difficult. There are two reasons. First, it could be leakage of servo fuel/brake fluid from the master cylinder on the clutch side or it could be due to the wear of the pressure plate.

The compressor is service as one unit. remove the belt and shack the pully if it wobles the compressor bearing is toast.

make sure your plugs and wires are in good condition.also fuel and air filter.the engine has to be well tuned up.because air conditioner compressor put a little load on engine.if engine is not well tuned.the AC will pull it down.cause it to lose power and run rough.

It's quite possible that your A/C compressor is locking up, thereby causing excessive load on the engine.(translates into lack of power to drive wheels) Typically there are signs, such as the noises you heard, or a slipping or thrown belt. If the compressor is locking up, being belt driven it will draw excess power from the engine. It's also possible that the compressor clutch in conjunction with compressor is going bad as well (both are usually related). That would cause excessive amperage to be drawn through the circuit, thereby blowing the fuse. Ultimately, it sounds like you have figured out your own problem, but I hope what I've posted helps.