I have a 1993 honda prelude si,2.3L and a timing light but i dont know how to time . where are the timing marks . when i look through the window all i see see are two teeth marks. and also what is the idle speed suppose to be .are you suppose to have in gear or in neutral for both idle speed and timing and also what hoses do you disconnect for timing.

SOURCE: 1993 honda prelude si dash lights

my 93 prelude was doing the exact same thing and for me it was my alternator was working properly.
go to a parts store and have them test it.

Alan Timperley

• 91 Answers
• Posted on Dec 08, 2008

SOURCE: rising and falling idle

Hey, first i would check all of your vacuum hoses. Over time they can crack and leak and that can create the problem, then the computer compensates to correct it. The throttle position sensor could also be a possibility and in combination with a vac leak, can create a wide variety of symptoms that are difficult to separate and trace down. Get a can of carb cleaner with the little spray straw, start the engine and let it idle to warm up. Spray a little on each vac connector, around the base of each injector or the throttle body, and see if the rpms run up. If so, you may have found a leak that needs tightening down. Vacuum hoses can sometimes just have the split end cut off and reconnected. The hard plastic spaghetti lines may be so brittle they need to be completely replaced. Manifold and throttle body bolts can be tightened up, but occasionally the gasket may need replacing. I would start with that and see what it does for you. Let me know if I can be of any more assistance.

SOURCE: hi was enquiring what would it cost to fix a head

yes car may not start if gaske is blown ,low compression or coolant in cylinders. price 750.00?

SOURCE: where is the timing marks

The timing marks are on the timing belt cover on the front of the engine right above the crankshaft pulley.