Won't start in warm weather.
 

Hi, I have a '90 Integra, all stock. Car won't start when it's been sitting in the sun (turns over but won't catch or if it does it dies right away), but later in the evening fires right up. Also stutters a bit under light throttle.

Hasn't had a tune up in a long time, but did replace the plugs recently.

I'm new to working on Honda's, but have pulled codes and worked on Ford engines, so should be able to figure it out with a little guidance. Any advice on pulling codes, where to start first etc?

Couldn't find any similar problems in search, don't Honda's every have start problems?!

Thanks.

G.

Sounds like your main relay to me.

It is located under the dash. You can either open it up and re-solder the connections that have become loose or you can just replace it with a new one.

Thanks, I'll check it out.

I was thinking it was fuel or sensor related, but as I it seems to be effected by the heat of the day, but not the heat in the engine bay, this might be a better place to start.

The main relay controls the fuel pump. The excessive heat in the cabin will cause the broken solder joints within the relay to expand too far causing an open circuit.

I have it out, all the joins look fine, but I'd like to do a continuity test. Haven't been able to find any free online diagrams. Know of any?

Thanks again!

Didn't have a diagram, so did the low tech version, stuck the relay in the fridge for a while, popped it back in and car started right up, took it out and heated it up, after installing car started but stalled immediately and then wouldn't restart.

Doesn't look like the unit come apart, other than the cover coming off, so will get a new one and see if that solves the problem. Thanks for the help.

If you just re-solder all the solder joints it does the trick. worked for me

nice job with the diagnostics. Soldering is the way to go. You don't need any more solder just touch each joint long enough to melt it for a second and then let go of it. the joints in question are the big ones on that main board underneath the cover. search the civc forum, there plenty of post on this there and somewhere there is a good DIY for the solder trick. if you get a new one make sure it is actually new. I wasted $20 for a one from a JY that had the same damn problem.