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There are a couple common concepts in automotive lingo that we need to clear up here.
1. Engine cranks but no start = Starter cranks but the engine doesn’t fire up.
2. Engine wont crank to start = No starter activity to crank the engine for start.
Which one do you have?
thats a good point, its hard to tell if we are dealing with a crank/no start or nocrank/no start. If its not cranking I would suggest checking Erics vid about starter diagnosis.
Jacob posted above earlier on what to test to rule out some components. Did you follow his direction?
do a good visual inspection of the wires and see if you can find something. No voltage to coil=no start, simple as that.
I dont know much on hondas but it does sound like it could possibly be a main relay too. Eric has a video about main relays if you are interested.
1. Test the coil and igniter in the distributor by removing the distributor cap and rotor. The Black/Yellow (BLK/YEL) wire should have battery voltage, key on engine off. Also, the coil negative wire should have battery voltage.
2. The Yellow/Green (YEL/GRN) wire should have 9 to 12 volts produced by the igniter.
3. When the YEL/GRN wire has the correct voltage, all the Engine Control Module (ECM) does is pulse the voltage to ground so spark will occur. This signal can be checked on a scope or a dwell meter. The signal should be a square wave signal on a scope or 10 to 14 degrees of dwell on a dwell meter on a 4-cylinder scale.
4. If the signal is correct, look for a trigger signal on coil negative. If there is a signal on coil negative, replace the ignition coil. If there is no signal on coil negative, replace the coil and igniter.
Does the fuel injectors have a pulse?If you find a problem inside the distributor you can just put the whole distributor in it cheaper than buying all the parts separate.
Thanks for the imput on the top of the ignition coil there is the negative and positive side i checked voltage there. Was i wrong for doing it that way? I don’t have many tools at all and not very knowledgable with all the names of tools. I plan to pull the main relay today to try to figure out how to test it. I hear the fuel pump humm for a few seconds is all I know. I checked the wires out yesterday they all looked good except under neath the dash by the fuse panel there is a black and blue wire that is twisted together from god knows where. I would like a fuse panel layout and wire diagram for the car with out paying if anyone has any ideas please help. I am a newb so all help is appreciated.
When you turn the key, what exactly happens. Does the car crank or is there no sound at all? Just trying to get a better idea of what is exactly happening. When did your car start having this problem?
When the car is in the on position all the dash lights come on and go off and the fuel pump hums and then it stops after a few seconds other than that nothing i checked all the fusses under the hood they are all good but under the dash there is a lot of bare spots in the fuse panel and i don’t know if there is suppose to be or what plus i want to make sure that all the spots have the correct fuse in it. the two wires i saw bare i am trying to figure out where they go and to what they go to. the car i bought for a dollar from a buddy who was driving down a road and it just died on him he had it 9 months and just stopped funny part was he was going to trade it in for a new car
LIke I was saying i had originally thought it was just a dead battery replaced it checked all the plugs they were bad so replaced them and the plug wires. After hearing that the distributor cap could be bad i looked and the points where dirty and some looked broke so i replaced it. While i was there I replaced the rotor on it as well.The local repair guy said that the coil are known to go bad on them so he told me to check the ohms from the positive and negative spots on the side. I got .9 to on the top he said that it was ok and then from where the cap sit on it to check from there to the negative side and i got 15 he said that he was ok but i replaced it anyway thinking sure enough that it was good enough I put it together and still no start or spark. So i broke it back down and checked the possitive and negative side and no voltage at all so i traced the wired to the fuse panel under the hood and all of them were all good. So i was told to check the main relay. Am I going the wrong direction with this or Am i getting close.
yes check the main relay. http://www.youtube.com/watch?v=viIZ8k60awY
Here is the diagram of the main relay.
I would run through this tree with a simple test light or preferably a dvom.
1. Verify that the Black/Yellow (BLK/YEL) wire on the igniter has battery voltage Key On Engine Off (KOEO). Verify that the coil positive and negative has battery voltage KOEO.
2. Test the White (WHT) wire at the igniter. It should have 9 to 12 volts produced by the igniter. If there is no voltage, and the igniter has power and the distributor and igniter are grounded, then the igniter is faulty. If the WHT wire has the correct voltage, the Engine Control Module (ECM) pulses the voltage to ground so spark will occur.
3. Test the signal on the WHT wire with a scope or a dwell meter. The signal should be a square wave signal or 10 to 14 degrees of dwell on a 4-cylinder scale. If the signal is good, look for a trigger signal on coil negative. A jumper wire can be used to manually try and trigger spark, back probe and pulse ground on the WHT wire or terminal of the igniter. The igniter should pulse coil negative and spark should occur. If there is no spark, check for a trigger signal on coil negative. If there is no trigger signal, the igniter and coil will need to be replaced
OK the starter turns but the engine won’t start so that is crank no start correct. How do i check the main relay and can someone one hook me up with a wire diagram and fuse panel under the dash layout and fuse I have a blue and black wire that is stripped and twisted together under neath the dash by the fuse panel and i would like to know what they go to if they need to be connected to something else or what
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