Mitsubishi Repair: 93 3000GT SL Starting and Idling problems, airflow meter, vacuum leak


Question
I have a manual 93 3000GT SL and over the past year the starting has been getting worse.  When I hit the starter, it sometimes clicks behind the dash somewhere.  It does this for a while and then eventually starts.  That was until last week, I tried for 15 minutes but no luck.  If I would get out and push the car a little while in 5th gear to turn the motor over and the starter too, it would usually start.  That is what I thought the problem was, the starter, but Checker said that the  starter checked out.  However, the positive lead (stud) on the starter was loose,  so we put a jam nut on it securing it down, but that still didn't help the starting.  It is still random when it wants to start right up and when it wants to click.

Also the idle is very low when it wants to idle at best.  I usually have to hold the gas pedal down slightly to keep it at 1000 rpm. Sometimes, it will idle on its own if I ease the pedal there very slowly, but it is down around 500 and very rough.  Then at other times the idle will be around 1000 then it will jump up and down on its own between 1000-1500.  I thought this might have been from a vacuum leak but looking under the hood of one of these cars is just intimidating.  

From reading other problems, I have found that the clicking is usually from an ECU going out.  Let me know what you think.  Thanks.

Answer
Corey: What of the solenoid which is part of the starter? Your clicking noise reminds me of a bad solenoid. How about your battery and the cables could they be loose? Sometime the battery has enough power to make the lights and radio to work but not turn the starter fast enough to start the engine. So you got a manual for your car, in mine it talks about a vacuum leak, check mounting bolts/nuts at the throttle body and the air duct between the airflow meter and throttle body for tightness, ensuring there's is no possiblity of air leaking at the gasket surface, at duct connections or through rips in the duct. Make sure all the vacuum hoses are connected properly and in good condition. You can get a stethoscope of a lenght of fuel hose head against your ear to listen for vacuum leaks while the engine is running. A hissing sound will be heard. Especially check the throttle body and intake manifold gasket areas and also the points where the fuel injectors enter the engine(the O-rings sometimes harden and allow vacuum leaks). The books says check your EGR valve. Check for bad stark plugs, stark plug wires that are shorting out or damaged, check your distributor cap/rotor damaged or carbon tracked. Air filter clogged, fuel pump not working right. Leaking head gasket, timing belt and/or pulleys worn. Camshaft lobes worn. Could be your computer too, have it check out. All that for a very low idle, could be a weak sensor but checking your computer by coding the car would show that too. By having your car coded, got a AutoZone close by? They will code your car for free. Hope this helps and good luck!