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Discussion Starter · #1 ·
read all steps completely before attempting it, then go back and read each step AS you do it if you need to, to make sure you do it exactly as it should be done

proper procedure to set the idle and ignition timing:
-warm the car up to normal temp by driving around for 10 minutes or so.
-turn the car off. jumper the service connector on the left side of the vacuum box on the firewall (yellow rubber boot) by inserting a wire or paperclip into both terminals of the plug
-restart the car. check the CEL, it should be on solid. if its flashing, you have codes stored. if the cel is not solid or flashing, then the jumper in the service connector is not making a good enough connection. fix it lol
-unplug the eacv (idle valve, aka electronic air control valve, aka iacv idle air control valve, front side of the plenum). the cel should now be blinking a code 14.
-if the car stalls, turn the idle screw out 1 full turn.
-turn the idle screw in and out however you need to turn it to get the idle to sit at about 650-700rpms. the idle screw is a flathead screw in the top of the throttle body. turning the screw in lowers idle, out raises idle.
-here is where you would check/adjust ignition timing at the distributor with a timing light if you so desire or need to. connect the pos and neg terminals of the timing light to the battery, and put the pickup lead on either cyl 1 or 4.
-point the timing light at the hole in the tranny bell housing next to the engine stamp, and you should see the timing marks on the flywheel. you want the middle of the 3 timing marks to be lined up with the pointer.
-if the middle mark of the group of 3 marks is not lined up with the pointer, loosen the distributor bolts and turn it ever so slightly each time and check the marks with the light again until the middle mark does line up with the pointer. once it does, tighten ONE distributor bolt. then check marks again to make sure it hasnt moved. keep adjusting until after one bolt is tight, the middle mark is lined up perfectly with the pointer. then tighten the other 2 dist bolts.
-plug the eacv back in, remove jumper wire from service connector, turn off the car and remove the keys from the ignition.
-reset the ecu by removing the clock fuse for a minute or so. replace fuse and start car and enjoy the new normal idle

this was requested to be added to the FAQ sticky, so had to create this thread to do so
 

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have any pics of where the service connectors are at? i never tried this procedure before.
 

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hey steve, is there any way i can turn down that high half of my idle, this morning on the cold start it jumped up to 3k and then started doing the up down thing from 3k to 1.5k... you mentioned something about a fast idle... i haven't made it home yet to look at the repair manual, but that fast idle is a serious issue... can i turn that down until i get the butterfly valve fixed...????
 

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Check the FIV adjustment.

There is a little brass capped doodad on the back of the manifold next to the TB, it has two screws holding it down.

Remove those screws, and remove the cap.
Then look inside, you'll see a doughnutish plastic thingie with two slots in it.
Put a large screwdriver in those slots and screw it down untill you can see a full ring of threads around the outside of it.

Then replace the cap and such.
 

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Yeah.
If it's running the idle will go through the roof :D
 

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hey motomann... i have no signs or letters around my hood and stuff...its all gone...still needs pics to see what you are talking about....
 

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Discussion Starter · #15 ·
follow your vacuum lines to the big black box on the passenger side of the firewall. now look on the left side of that black box for a metal bracket with a yellow rubber thingy attached to it, and a plug inside that yellow rubber thingy. if its not attached to the metal bracket, it should be right there somewhere to the left of the black box.
that plug inside the yellow rubber boot thingy is the service connector. that is the part you stick a wire in to "jumper" (connect) the two wires of that plug together. once you jumper that connector, it throws the ecu into debug mode which makes the cell blink any error codes, forces the ecu to ignore all compensation levels, and a few other things that even i dont understand sometimes. but it basically forces the ecu to read values directly from the mapping in the ecu instead of doing math and changing those values according to other sensors.

you need to do it for the ecu to output the correct ignition signal to set the ignition timing, and so the car idles somewhat steadily to be able to adjust the idle with the idle valve unplugged
 

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does it work on cars that have obdo to obd1 conversion on the ecu???
cuzz thats what i have.....

i am using a p28 civic single over head vtec ecu......and my car is a 89...
 

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i know i read somewhrere about it, but i can't seem to find it so here it goes:

I had my flywheel lightened and i have a problem with getting the thing timed right. My motor is out and it has no timing belt on it. What is the proper way to mark my unmarked flywheel so that i know exactly where tdc is and exactly where the other ignition timing marks should go?
 
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