No maximum power

Step 1: Is ignition system in proper condition?

Check battery voltage, ignition distributor, spark plugs, ignition coil, ignition timing, etc.

• Yes: Go to Step 2
• No: Repair or replace damaged ignition components

Step 2: Is engine in proper mechanical condition?

If maximum power still cannot be attained after the electrical test, check for mechanical problems: Compression, basic adjustment of valves and engine oil pressure.

• Yes: Go to Step 3
• No: Repair or replace damaged components

Step 3: Does the throttle valve open completely?

Check condition of throttle linkage and accelerator pedal. Straighten bent linkages as necessary. Watch for sticking accelerator pedal (caused, for example, by a floor mat etc).

• Yes: Go to Step 4
• No: Repair as necessary

Step 4: Is the fuel pressure correct?

Test fuel pressure according to Test Chart.

• Yes: Go to Step 5

Step 5: No leaks in air intake system, system in proper condition?

See Engine does not start Step 8.

• Yes: Go to Step 6
• No: Repair leaks

Step 6: Is the quantity of fuel delivered by the fuel pump correct?

In order to test the quantity of fuel delivered detach the fuel hose at the start valve. Extend the hose and lead it to a measuring vessel of 5 liters capacity with a graduated scale. Remove the top section of the air filter, open the air-flow sensor flap by hand until the pump operates. Measured value for correct delivery (after 1 minute of operation) about 1.5-2 liters per minute.

• Yes: Go to Step 7

• No: Check for the following conditions and repair as necessary:

  • Fuel filter clogged (replace)
  • Fuel-pressure regulator defective (replace)
  • Fuel pump power too low (replace)

Step 7: Is the air flow meter in proper mechanical condition?

For testing, see Engine does not start Step 9.