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Discussion Starter #1
Alright, I just obtained a 1990 Honda Prelude. Its a DOCH 2.1. It doesn't seem to be running the fuel pump (I cant hear any humming) and it definatly doesn't have any spark. What should I check or test for to resolve these problems. Could the master relay be at fault? Can it be repaired? Or does it have to be replaced? The ignition system is getting power, but it doesn't fire. Any ideas?
 

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Simple way to test if you have any fuel pressure:

Turn the key in your car, make sure the CEL goes out with a click. Then unscrew the pressure relief valve on the fuel filter, the black canister on the firewall.

Spark:

Remove a wire, stick it next to the block and crank and see if its sparking.
 

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Absolutely check your main relay. I can post the test instructions from the repair manual later. If you've got a multimeter just go ahead and check the connector to the fuel pump (behind rear seat under driver side gas tank plate) and ensure it has power with ignition on.
 

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Discussion Starter #5
Alright, I've done some further testing. I found that a bad fuse had caused my main relay to not function. It was a 10 amp fuse 3rd one from the left on the top row in the cab i think. Upon replacing the fuse I discovered that once i turn the key into the "on" position it will display the check engine light for a few seconds and then it will turn off. I still could not hear my fuel pump, so I investigated. once the check engine light turns off. voltage to the fuel pump turn off aswell. at the exact same time. Also! Still no spark! I went through the testing procedure for the main relay and it tested good. Any ideas guys? :/
 

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Remove the distributor cap and see if the cap and rotor are in good shape. If not, replace. Did you test the spark as I suggested?
 

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Discussion Starter #7
Alright, the distributor seems to be in good shape on the inside, nothing is broken off or cracked, no rust or buildup or any kind. That same fuse keeps blowing. There must be a short somewhere. I found a small rats nest in the trunk. Let me find out what that fuse actually goes to really quickly.
 

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I'm 403'd from viewing that image. Rehost to imgur.com
 

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When you turn the key on the fuel pump primes itself for 3 seconds and then shuts off that's why you're losing power to it. The pump only runs continuously after your engine has started
 

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Discussion Starter #12
Alright, the fuse was blowing because my pump had rusted solid. I've replaced it. Is it possible that the spark issue is related to fuel pressure? (almost certainly not) Does this car have an ignitor? Where is it located? It there a procedure for testing it or the distributor?
 

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igniter is about 1 1/2" square black plastic box right next to the coil. Test in the online manual. See if it is producing current to go to the coil.
 

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What do you mean ICM? That is usually what people call the igniter. You have an igniter. I told you where it is. You need to look at the shop manual or get a helms electrical trouble shooting manual. And see if it is getting voltage to the igniter with the key in run. Then the shop manual has a test for the igniter. You can take the connector off the coil to and check to see if it is getting voltage on the correct terminal from the ingniter. If you are then you can hook the connectors back up and disconnect the coil wire from the top of the distributor cap and touch it to the engine to see if your getting spark out of the coil. There is also a test for the coil I think. Also you don't have to disconnect the coil lead to distributor if you buy a $10 lisle spark indicator pen light that magnetically lights up when you place it on the coil wire or spark plug wires. It is in my oddball and large tool thread in the red F.A.Q. sticky on top of 3rd gen forum.

If the fuel pump was all rusted up I would jack up the rear on jack stands under the rear plates of back of the rocker panels under the doors. Then take off the driver's side rear wheel if needed and access the fuel tank drain bolt and totally drain it and replace the bolt and add new gas then replace the fuel filter at the firewall in the engine bay.

But as for your no spark it could be the ignition switch I would think. But if your getting voltage to the igniter maybe not.

Also if you meant the ECU (Electronic control unit), computer, That is unlikely and you would want to swap the main relay with a good brand new one before thinking it is it. Because the main relay is a dual relay and it sends voltage to the fuel pump and ecu both.
 

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Yeah that is the igniter.
 

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Sorry for the confusion. Yeah the shop manual probably calls it ICM (Ignition Control Module), it had been so long since I heard it called that. Igniter is easier to say and that is what it normally is called here and I think most Honda guys call it that. Even though I have the helms reprint of the factory shop manual and electrical troubleshooting manual (ETM) I rarely look at them anymore unless I want to find out something specific like torque rating of a bolt or the bolts thread pitch I think is also mentioned in the shop manual.
 

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Discussion Starter #20
Alright, the new ignitor came in and I'm still not getting any spark :/ I have no idea what else could be causing this
 
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