94 Prelude si - starts good first of the day..drive or warm up is good. After it gets to optimum temp, I shut it down and then it WIL NOT START. Turns over fine and just almost starts one chug, but hten it just cranks. Seems like heat is giving me some grief. Just got the car and am not sure of location of all relays or sensors that may apply. My friend Chilton was no help either.

 

check the main relay, it seems to be giving some people problems....

Neil

 

main relay, happens all the time... do a search

 

OK, so don't laugh...it is Sunday and I'm waiting for the freakin dealer manana...where is the main fuel relay to be found. Or is it labeled diff...like egr or whatever?

 

its under the dash, lay on the floor and look straight up. its a bitch to unbolt. i would recommend zip tying the new one somewhere under the dash. its a pain to bolt it back in the original spot

 

Found a diagram for it and maybe some diagnostics, voltage and so on. Is this fairly common, or maybe the age and mileage have created the situation?

 

I've had the same problem and still do. Mine actually signals a cel 3 - map sensor once it gets running. I've changed my main relay but didn't help. Keep it posted if you find anything out.

 

Think I'm gonna have to get a little kid to get in there. Is this above and in front of the blower motor housing?

 

You have to get under the dash and look up. It's not really under the dash on the firewall but on the fender/wheel well side. Little grey box with a plug. The easiest way to get to it is to pull out the wire and then unclip andl open the box rather then try to unscrew the whole housing. It's a pain one way or the other though.

 

an easy way to check if your main relay is the problem is to turn on your ignition switch to the on position. the check engine light should come on for a sec or so then shut off, if the light doesnt shut off its almost always the main relay. if the light doesnt shut off and it stays on give the dash a good kick a few times and the light will shut off. if that solves your starting problem it is the main relay. I know it sounds dumb but I have had this problem in many hondas that I have worked on.

 

Sounds right, and I got to talk to a tech this am. Based on experience, he said useful life starts to diminish after 100K and they see failures b y 150K. Going to have a new one on wednesday and will let you know how I fare. The removal process doesn't have to be too difficult either. For anybody tghat is wondering...remove the panel from under the steering column, drop the metal reinforcement webbing (four bolts), and then wiggle the air ducting back and forth. You should be able to pull it to the right far enough to pop it out of the vent duct. Look on the left side firewall and the relay is unmistakeable. Mine is RZ-0139, gray, and reads Relay Assy, Main on the side. The bolt on the hangar bracket is hard to get to, so I recommend using a thin, flat tool (six inch rule or similar) to get between the bracket and the relay. The plastic is fairly fiable, so you should be able to slide the tool up and disable the snap lock. Then just push up on the relay and it will pop off the bracket. (Found all this out afterwards). Good luck!