My '90 Honda Accord EX wont start. I have replaced the master relay, and a rebuilt distributor, the engine cranks but won't start. The "check engine light" does not come on at all when the ignition is switched on. There is no problem with fuel, the spark is not bright blue/white but yellowish and weak. The battery is brand new. Can someone please help especially with CEL that won't come on. Thanks.

 

http://techauto.awardspace.com/ecu.html

give this a go..

 

I only skimmed that real quick, but I didn't see a check for the bulb being burned-out??
Check the simple stuff first.

 

If the "Check engine" light does not come with the ignition ON, it's possible that there is no power coming to the engine computer (e.g, due to a broken wire, faulty relay, burnt fuse, etc.) or that there is a problem with the engine computer itself.

Sometimes a car may have an intermittent problem, when it starts fine most of the time, but once in a while it doesn't. Such problems, that are not presented at all times, could be very difficult to diagnose. What will help your mechanic to find such an intermittent problem is if you notice when, under what conditions the car doesn't start and what helps to get it started. For example, if you notice that wiggling the ignition key helps to get the car started, it may tell your mechanic that the problem is likely with the ignition switch (very common problem). Or if the security light flashes on the instrument panel each time the car doesn't start could tell your mechanic to begin with checking anti-theft system.

 

If it was just a burnt bulb the car should start ,,,,,,,,,,,,,,He also has a no start condition

 

If there was no power coming to the ECU, there would be no spark whatsoever. He says there's a weak spark.

If he has had a burned-out bulb for a long time (not noticed) then maybe NOW it's trying to throw a CEL code but it can't.