Main fuel relay quick fix.
*I dont take credit for this. However I have been having some trouble with my car starting for a while. I have searched like crazy. After looking and testing ingiton, starter, alternator, fuel pump. It was the main relay... I was able to re solder it and save big money. (also have a back up on the way for later just incase) There are some other things I did to find out that this was the problem, didnt know what to search for for a long time. PM me if you have any questions. Tom I was not sure if you would want to move this since is it some what a how to. But then again targeted to 4gs mainly so I thought it would help out best here. Sorry if you feel like the needs to be moved. *
So, your 88-91 Fuel Injected Honda Civic won't start? Many people here had similar problems (including me), and I'll try to explain a few troubleshooting tips that might help you get your Civic running again. Even if your Civic is a bit older, or a bit newer - you might find some interesting informations here.
One of the first things you want to do when you have problems with your Civic is to check your ECU / ECM (Electronic Control Unit / Electronic Control Module) for error codes. It is a metallic box, placed under the carpet, below the glove box, where a passenger would usually keep his/her feet while driving. Pull the carpet down a bit, and you'll see it. There will be a circle on the metallic sheet, which is just an opening through which a red LED light can blink. When you turn the key to position "II" (when the Check Engine Light, Oil light and Battery light turn on, but you do NOT yet crank the car) the LED will blink once, as if it's saying "Hello there, I'm alive...". That LED will report any error codes it might have stored after the initial hello-blink. Error codes are coded with blinks as follows: number of short blinks = error code, pause = another error code is coming now. For example, if you're getting a "HELLO_BLINK-pause-blink-pause-blink-blink-blink-blink" it means the ECU stored error codes 1 and 4. Once all error codes are "blinked" (displayed), ECU will "reblink" them again. Notice that if you're getting something like this: "HELLO_BLINK-pause-blink-pause-blink..." it means that ECU has an error code 1 stored. If there are no error codes, then the ECU will just blink once and will not blink again.
After you've written down all your error codes, you can search online for an error code list. You can find an error code list on www.4thgenerationcivic.com
Now error codes might give you an idea as to what's going on. One of the very common error codes you can get is 16. It means there's an error with Fuel Injection System. Now, don't go running right away, trying to replace fuel injectors. If your car is having a hard time starting in a hot weather (after being parked in the sun for an hour or so), or if you shut it down, go to the store, come back and it won't start, AND you check your ECU and see an error code 16 - you most likely have a bad Main Relay. It's such a common thing with Civics. Now don't either go running to the store to buy a new one. All you have to do is take out your old Main Relay, resolder it's joints, and put it back in. I did that to my car (it experienced the same problems i described above) and it's starting every time since i did that. Detailed instructions on how to "DIY (Do It Yourself) Main Relay Fixing" can be found here - http://www.markl.f9.co.uk/howto/ele.../main-relay.htm
When you're done with fixing the car, have your negative battery cable disconnected from the car for about 20-30 seconds. It will erase the ECU memory of error codes. It will help you notice any new error codes once you see your car is having troubles again.
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Procedures to check if your Igniter Unit or Ignition Coil is bad.
In order to reach the Igniter Unit, you should remove the Distributor Cap and Leak Cover, which is a plastic thing just under the Rotor (it might help if you remove the rotor as well). Ignition Coil is on top of the distributor (you'll only see it if you remove the Distributor Cap) and the Igniter Unit is a match-box like unit, just under the rotor. You can see it once you take the Leak Cover off. Now you should see 4 wires connected to the igniter: WHT, BLK/YEL, WHT/BLU and BLU.
Now here is how to diagnose problems with the Igniter Unit:
Check for voltage between the BLK/YEL wire and the body ground with the ignition switch on. There should be battery voltage. If there is no voltate, check for an open in the BLK/YEL wire between the igniter unit and the ignition switch.
Next, check for voltage between the WHT/BLU wire and the body ground with the ignition switch on. There should be battery voltage. If there is no voltage, check for: faulty ignition coil or an open in the WHT/BLU wire between the igniter unit and the ignition coil.
Next, check for continuity between the WHT wire and the body ground. There should be continuity. If there is no continuity, check for: and open in the WHT wire between the igniter unit and the ECU or poor ground.
Next, check for continuity between the BLU wire and the body ground. There should be continuity. If there is no continuity, check for: and open in the BLU wire between the igniter unit and the tachometer (or the A/T control unit) or poor ground.
And if all continuity and voltage tests are normal (with a known good 50A fuse), but the engine won't start - replace the igniter unit.
Here is how to diagnose problems with the Ignition Coil:
There is a BLK/YEL and WHT/BLU wires connected to the coil. Call the terminal to which the BLK/YEL is connected terminal A and the other one terminal B. The circular thing on the side of a coil is a secondary winding terminal. Switch ignition to OFF. Remove the screws and disconnect the wires from terminals A and B. Using an ohmmeter, measure resistance between the terminals. Replace the coil if the resistance is not within these specifications: between the A and B terminals - 0.63-0.77 ohms, and between terminal A and secondary winding terminal - 9,760-14,640 ohms.
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If everything above turns out to be ok, problems with starting might be caused by not getting a spark, not getting fuel or by your timing being off.
To check if you're getting fuel, the easiest way would be to pull out your injectors (if you have a fuel rail and 4 injectors (all 1.6 liters Honda Engines have 4 injectors, only 1.5 liters DX has 2 injectors)) with the rail still connected to them (and electrical connectors connected to them too), pointing them to somewhere that will not ignite the fuel once they (if they) squirt gas out, and have someone crank the car while you look if gas is squirting out. If the gas is not squirting out, you now know that your car is not starting due to not getting gas to the injectors. It might be caused by clogged fuel filter, clogged fuel lines, non-working fuel pump (make sure you check for Main Relay before this, because Main Relay gives power to the fuel pump - if your Main Relay is not working fine, and you DON'T check it first - you might beleive that your fuel pump is not working, and be amazed that your newly bought fuel pump is not working either, all because of a Main Relay) or no gas in the tank (a long shot, but hey...). If you are getting gas, then connect everything back (injectors into the intake manifold) and go on checking for spark.
Now for spark - I'll quite labman..."If it has spark plug wires, pull one off and hold the terminal near a ground while somebody cranks the engine over. If you don't get a spark, start checking the ignition system." So, since we do have spark plug wires, pull one off, hold it with something wooden (to not get sparked yourself) near to the chassis and see if you're getting a spark on each spark plug wire. If you're getting a spark on each wire, then the only problem might be wrongly set timing. If you're not getting a spark, and ignition coil and igniter unit both test fine, then either spark plug wires or distributor cap and rotor must be replaced (wires, cap and rotor are cheap things...you should replace them all if you're not sure when you last replaced them).
-----
Maintainance tips
Check your oil regularly. Do not allow your engine to get low on oil.
Have your valve clearance adjusted every 15000 miles, or 1 year, whichever comes first. Unudjusted valve clearance might cause your mileage to drop down, and your car will run worse as a result of lower compression.
Do replace your spark plugs, spark plug wires, distributor cap, distributor rotor, fuel filter and air filter if you do not remember when you last changed them. You won't beleive the change once you do replace them.
Have your tires properly inflated. It can do wonders to your mileage.
-----
Final notes
These are just quick tips for those who think they can perform the work on their car themselves. If you're not confident about doing it - don't do it. It's not hard to do, but if you do not understand what you're doing, you might break something, and I don't want to be held responsible for that.
Search the net, learn about your car...all the knowledge that i have about engines and about cars, i learned on the net. At the time of writing this note, I learned about engines for only 8-9 months. Before 8-9 months i couldn't point at an engine head while the hood was opened, and now i'm not afraid to work on my car myself.
As a final notice, let me just give you a link to my web page, where i documented some work i did on my car - http://public.carnet.hr/~kpuljic/honda/
You can find pictures I took while replacing distributor cap and rotor, if you need to know how the inside of the distributor looks like before you open it.
Enjoy your car and drive safe!
*I dont take credit for this. However I have been having some trouble with my car starting for a while. I have searched like crazy. After looking and testing ingiton, starter, alternator, fuel pump. It was the main relay... I was able to re solder it and save big money. (also have a back up on the way for later just incase) There are some other things I did to find out that this was the problem, didnt know what to search for for a long time. PM me if you have any questions. Tom I was not sure if you would want to move this since is it some what a how to. But then again targeted to 4gs mainly so I thought it would help out best here. Sorry if you feel like the needs to be moved. *
So, your 88-91 Fuel Injected Honda Civic won't start? Many people here had similar problems (including me), and I'll try to explain a few troubleshooting tips that might help you get your Civic running again. Even if your Civic is a bit older, or a bit newer - you might find some interesting informations here.
One of the first things you want to do when you have problems with your Civic is to check your ECU / ECM (Electronic Control Unit / Electronic Control Module) for error codes. It is a metallic box, placed under the carpet, below the glove box, where a passenger would usually keep his/her feet while driving. Pull the carpet down a bit, and you'll see it. There will be a circle on the metallic sheet, which is just an opening through which a red LED light can blink. When you turn the key to position "II" (when the Check Engine Light, Oil light and Battery light turn on, but you do NOT yet crank the car) the LED will blink once, as if it's saying "Hello there, I'm alive...". That LED will report any error codes it might have stored after the initial hello-blink. Error codes are coded with blinks as follows: number of short blinks = error code, pause = another error code is coming now. For example, if you're getting a "HELLO_BLINK-pause-blink-pause-blink-blink-blink-blink" it means the ECU stored error codes 1 and 4. Once all error codes are "blinked" (displayed), ECU will "reblink" them again. Notice that if you're getting something like this: "HELLO_BLINK-pause-blink-pause-blink..." it means that ECU has an error code 1 stored. If there are no error codes, then the ECU will just blink once and will not blink again.
After you've written down all your error codes, you can search online for an error code list. You can find an error code list on www.4thgenerationcivic.com
Now error codes might give you an idea as to what's going on. One of the very common error codes you can get is 16. It means there's an error with Fuel Injection System. Now, don't go running right away, trying to replace fuel injectors. If your car is having a hard time starting in a hot weather (after being parked in the sun for an hour or so), or if you shut it down, go to the store, come back and it won't start, AND you check your ECU and see an error code 16 - you most likely have a bad Main Relay. It's such a common thing with Civics. Now don't either go running to the store to buy a new one. All you have to do is take out your old Main Relay, resolder it's joints, and put it back in. I did that to my car (it experienced the same problems i described above) and it's starting every time since i did that. Detailed instructions on how to "DIY (Do It Yourself) Main Relay Fixing" can be found here - http://www.markl.f9.co.uk/howto/ele.../main-relay.htm
When you're done with fixing the car, have your negative battery cable disconnected from the car for about 20-30 seconds. It will erase the ECU memory of error codes. It will help you notice any new error codes once you see your car is having troubles again.
-----
Procedures to check if your Igniter Unit or Ignition Coil is bad.
In order to reach the Igniter Unit, you should remove the Distributor Cap and Leak Cover, which is a plastic thing just under the Rotor (it might help if you remove the rotor as well). Ignition Coil is on top of the distributor (you'll only see it if you remove the Distributor Cap) and the Igniter Unit is a match-box like unit, just under the rotor. You can see it once you take the Leak Cover off. Now you should see 4 wires connected to the igniter: WHT, BLK/YEL, WHT/BLU and BLU.
Now here is how to diagnose problems with the Igniter Unit:
Check for voltage between the BLK/YEL wire and the body ground with the ignition switch on. There should be battery voltage. If there is no voltate, check for an open in the BLK/YEL wire between the igniter unit and the ignition switch.
Next, check for voltage between the WHT/BLU wire and the body ground with the ignition switch on. There should be battery voltage. If there is no voltage, check for: faulty ignition coil or an open in the WHT/BLU wire between the igniter unit and the ignition coil.
Next, check for continuity between the WHT wire and the body ground. There should be continuity. If there is no continuity, check for: and open in the WHT wire between the igniter unit and the ECU or poor ground.
Next, check for continuity between the BLU wire and the body ground. There should be continuity. If there is no continuity, check for: and open in the BLU wire between the igniter unit and the tachometer (or the A/T control unit) or poor ground.
And if all continuity and voltage tests are normal (with a known good 50A fuse), but the engine won't start - replace the igniter unit.
Here is how to diagnose problems with the Ignition Coil:
There is a BLK/YEL and WHT/BLU wires connected to the coil. Call the terminal to which the BLK/YEL is connected terminal A and the other one terminal B. The circular thing on the side of a coil is a secondary winding terminal. Switch ignition to OFF. Remove the screws and disconnect the wires from terminals A and B. Using an ohmmeter, measure resistance between the terminals. Replace the coil if the resistance is not within these specifications: between the A and B terminals - 0.63-0.77 ohms, and between terminal A and secondary winding terminal - 9,760-14,640 ohms.
-----
If everything above turns out to be ok, problems with starting might be caused by not getting a spark, not getting fuel or by your timing being off.
To check if you're getting fuel, the easiest way would be to pull out your injectors (if you have a fuel rail and 4 injectors (all 1.6 liters Honda Engines have 4 injectors, only 1.5 liters DX has 2 injectors)) with the rail still connected to them (and electrical connectors connected to them too), pointing them to somewhere that will not ignite the fuel once they (if they) squirt gas out, and have someone crank the car while you look if gas is squirting out. If the gas is not squirting out, you now know that your car is not starting due to not getting gas to the injectors. It might be caused by clogged fuel filter, clogged fuel lines, non-working fuel pump (make sure you check for Main Relay before this, because Main Relay gives power to the fuel pump - if your Main Relay is not working fine, and you DON'T check it first - you might beleive that your fuel pump is not working, and be amazed that your newly bought fuel pump is not working either, all because of a Main Relay) or no gas in the tank (a long shot, but hey...). If you are getting gas, then connect everything back (injectors into the intake manifold) and go on checking for spark.
Now for spark - I'll quite labman..."If it has spark plug wires, pull one off and hold the terminal near a ground while somebody cranks the engine over. If you don't get a spark, start checking the ignition system." So, since we do have spark plug wires, pull one off, hold it with something wooden (to not get sparked yourself) near to the chassis and see if you're getting a spark on each spark plug wire. If you're getting a spark on each wire, then the only problem might be wrongly set timing. If you're not getting a spark, and ignition coil and igniter unit both test fine, then either spark plug wires or distributor cap and rotor must be replaced (wires, cap and rotor are cheap things...you should replace them all if you're not sure when you last replaced them).
-----
Maintainance tips
Check your oil regularly. Do not allow your engine to get low on oil.
Have your valve clearance adjusted every 15000 miles, or 1 year, whichever comes first. Unudjusted valve clearance might cause your mileage to drop down, and your car will run worse as a result of lower compression.
Do replace your spark plugs, spark plug wires, distributor cap, distributor rotor, fuel filter and air filter if you do not remember when you last changed them. You won't beleive the change once you do replace them.
Have your tires properly inflated. It can do wonders to your mileage.
-----
Final notes
These are just quick tips for those who think they can perform the work on their car themselves. If you're not confident about doing it - don't do it. It's not hard to do, but if you do not understand what you're doing, you might break something, and I don't want to be held responsible for that.
Search the net, learn about your car...all the knowledge that i have about engines and about cars, i learned on the net. At the time of writing this note, I learned about engines for only 8-9 months. Before 8-9 months i couldn't point at an engine head while the hood was opened, and now i'm not afraid to work on my car myself.
As a final notice, let me just give you a link to my web page, where i documented some work i did on my car - http://public.carnet.hr/~kpuljic/honda/
You can find pictures I took while replacing distributor cap and rotor, if you need to know how the inside of the distributor looks like before you open it.
Enjoy your car and drive safe!
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