| Check the O2 sensors at 2000 rpm for adequate on-off I think at least 5 in 10 seconds.Even if correct swing count the voltage range could be faulty so check the voltage swings with a digital only VOM at each injector at 2000 rpm (should be 0.1v - 0.9v if healthy, fluctuating around 0.5v replace O2. Also check the O2 heater circuit for proper Ohm range. Check for vacuum leaks with a gage, will also tell many other things, read here: [ http://www.atlanticz.ca/zclub/techtips/vacuum/ ] Check the engine warm up temp at the thermostat ( I use an infra red gun) if not high enough the thermostat is faulty and that will affect gas mileage because the computer thinks the car is in warm up cycle and sends signal to the injectors, if replace use OEM and check new with stove test before install. Faulty thermo that remained open to far and affected mileage happened to me. The throttle position sensor could need adjustment. The mass air flow sensor could be faulty or dirty. The coolant temp sensor could be faulty check Ohms. Check the timing. Do a decarb with fuel additive like Chevron Techron concentrate not their injector clean product, to mild.
Clean the throttle bodies with CAT and O2 sensor safe spray and a tooth brush (place rags to catch overflow from throttle body). While you are at it check all connectors (you can get at) and clean and dielectric grease them, also grease the battery post connections by removing cables, cleaning posts and inside cable clamp grease up and reinstall. As far as the old style injectors they will eventually fail so save up. In the meantime Ohm them when cold, good reading is 10 - 14 ohms. Try to use non E fuel and add some stable if tank not used in 7 to 10 days, it will keep the fuel system corrosion at a low and keep the fuel fresh if tank takes awhile to use. When you have time as a further help do a ground net system, cheap ($15+/-) and easy to do. Look up how to on this site. Welcome to the Z32 world
ZUL8TR in Orlando,FL |
05:55:26 11/22/14
