Engine Maintenance and Modification Bradley Artigue

More documents

Recommendations

Info

FIAT 124 Spider Engine Maintenance + Modification Component Description ECU P/N CU97X The ECU is a small computer located under the glove box. It is not a serviceable component. The connector on the ECU is used to test many of the sensors in the FI system. 5.10 Fuel Injection Tuning A fuel injected Spider does not require (or allow) mixture adjustment. Tune-ups typically include the steps outlined above (in “All Engines”), setting the idle speed, and adjusting the throttle position switch. The oxygen sensor should also be replaced if it is old or questionable. 5.10.1 Replacing the Oxygen Sensor How old is your oxygen sensor? Don't know? Replace it. Sensors are good for approximately 30,000 miles. However, if your engine is running very poorly then do not replace the unit until good performance has been restored. No matter what you’ve read or heard the oxygen sensor on your Spider is not going to cause the vehicle to run poorly. Most people are not aware when the O2 sensor fails because the changes in performance are typically minor. Certainly the engine runs better if all sensors are working properly, but the O2 sensor will not cause your car to go from running great to hardly running. If you’re having performance issues that are major look elsewhere and leave your old O2 sensor installed so you don’t ruin a new one (they damage very easily with overly rich or lean engines). 5.10.2 Idle Speed Setting. Run the engine to normal operating temperature. On cars with automatic transmissions, set the parking brake, block the wheels, and put the transmission in "D". Completely seat the idle speed screw. Loosen the accelerator linkage stop screw retaining nut and adjust the stop screw to achieve 800 to 900 RPM on manual transmissions and 700 to 800 RPM on automatic transmissions. 48
FIAT 124 Spider Engine Maintenance + Modification Figure 37: Idle speed controls on the Spider 2000 Lock the accelerator stop screw with the retaining nut. Use the idle speed screw (1) to set idle at 850 to 900 RPM on manual transmissions and 700 to 800 RPM on automatic transmissions. If idle speed cannot be reached using this procedure, fully remove the idle speed screw (2) and clean the orifice and the screw itself using a high pressure spray cleaner (carburetor cleaner is fine). 5.10.3 Throttle Position Sensor Adjustment The throttle position sensor tells the ECU to turn off the injectors during deceleration. Improperly set it can affect the travel of the throttle plates and cause poor transition from full speed to cruise and idle operation. Unplug the throttle plate switch. Note the connector blades (on the plate switch, not the connector itself) are marked “3” “18” and ‘2”. Connect an ohmmeter between terminals 2 and 18 of the switch. Loosen the two screws holding the switch in place. Rotate the switch clockwise until the ohmmeter indicates a closed circuit. Tighten the two screws and reconnect the switch. 49
Page 1 and 2: Engine Maintenance and Modification
Page 3 and 4: FIAT 124 Spider Engine Maintenance
Page 47: FIAT 124 Spider Engine Maintenance
Page 91: www.artigue.com/fiat

Engine Maintenance and Modification Bradley Artigue

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?