Hi everyone. I have a 93 Honda Accord Ex with auto tranny and recently replaced the spark plugs, distributor seal, and a cooling hose. It was running great for about a week until the summer heat kicked in, now it doesn't like to start in the heat of the day. It starts just fine in the cool mornings or evenings when the weather starts to cool down, just not when weathers hot. I was told it could be vapor locking, but my system is fuel injected and I thought vapor lock only happened on older models with a fuel pump. So now I am stuck with no transport and have no idea where to look next. Any suggestions?????

 

Welcome. This would be better in General Tech, so I'll move it.

Sounds like it could be your main relay, search for info on that. If you're good with a soldering iron, you can re-melt cracked solder joints on the circuit board.

 

main relay x2

 

Cool, I will check the main relay then. Thanks for the help!! And I will let you know what I find out.

 

Well I am sorry to say that, I replaced the main relay and the car still doesn't to start in the heat. It still has all the same symptoms.....anymore thoughts as to what might be going on? Thanks again for the help on this.

 

you should diagnose before starting to replace parts,,,,,,,I would have also said that it sounds like a bad main relay , that does not mean to just replace it, you need to make sure first.,,

Silly question without questioning your intelligence ,, but you are sure that you replaced the main relay correct ?? properly plugged in ? it was a new relay you got from the Honda dealer ??

When car does not start ,,you need to diagnose if it is lack of spark or lack of fuel,, that is test # 1 ...
if it is lack of fuel and relay is new, you need to see if you are getting proper power and ground at the fuel pump ,,
if it is lack of spark you need to test the ignitor and coil ..

try those and let us know

 

Thank you for the reply DesertHonda. And I understand your concern for diagnosing before just replacing parts. Checking for spark was the first thing I did, thinking maybe I did something during/after replacing the plugs and I get spark everytime. As for fuel, I can hear the pump kick in right before I turn the key to full ignition, so I don't think that is it. Also, like I said earlier, the car starts just fine when it is cool and I have driven it around the block a couple of times, just to see if it acts okay in relation to not getting proper fuel. And it does just fine, I don't see, feel, hear any problems.

So that's when I found this forum while looking on the internet for causes. And after getting the couple responses saying it was the main relay, I did go to the Honda dealer and get a new replacement part. Which the gentleman there also made the comment about car not wanting to start in the heat. I didn't even tell him what was going on, so that just reassured me some more that I was doing the right thing.

I followed these directions on how to replace:
http://techauto.awardspace.com/mainrelaydefine.html

But when I went to start the car (still 87 degrees out) it didn't want to start. I did take the wire assy out again and put it back in just to make sure connection was fine. Tried to start car again and to no avail, no running car.

But now, this morning, it is currently 65 degrees and the car is running and rearing to go, so I don't know what to tell ya.....getting a little frustrating to say the least.

Once again, I do appreciate the help on this matter.

 

i agree with desert. i made the mistake off spending 70 bucks on the main relay and my car still doesnt operate correctly.

 

Oh it operates just fine....when its cool out. I guess the car is starting to finicky like myself......boy I can't stand the heat when it gets over 80 degrees...LOL!

 

Just FYI, when you suspect a bad main relay, turn the key ON but not all the way to START. It's especially useful to check this when the interior of the car is very hot. You should hear the relay click, the fuel pump run for 2 seconds, then the relay click again & the pump stops. When the relay is bad, usually it clicks but the pump doesn't run.