warms up, then wont start on 1993 Honda Civic

where is the scanner port for 93 civic? engine cranks but wont start, in the morning it turns right on after it warms up and i turn off the car it just cranks and wont start. Thinkin map sensor or main relay. Suggestions please thanks.

by in Commerce City, CO on July 04, 2009
Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
4 answers 3 comments
ANSWER by , July 04, 2009
take a look at the Main EFI Relay. This is a known problem for Honda for quite a few years. If it doesn't start when the temperature is high and starts when the temperature is low, I'd be willing to bet its this relay and should be available at your local auto parts store.
ANSWER by , July 05, 2009
The main relay is under the dash on the driver's side but relay isn't sensitive to heat. If you locate the relay when the car doesn't start, hit the relay with a screw driver as you crank the engine over if hitting the relay makes the car start the relay is bad. http://images.google.com/imgres?imgurl=http://www.tegger.com/hondafaq/mainrelaylocation/7-main_relay_closeup.jpg&imgrefurl=http://www.hondacarforum.com/honda-3/21752-fuel-pump-relay-1990-honda-civic-1-5l-mt-4dr.html&usg=__36Q1E1J7fi-6scSB4zBqXT2DS0s=&h=480&w=640&sz=71&hl=en&start=1&tbnid=IXYe6Fc6P4tWLM:&tbnh=103&tbnw=137&prev=/images%3Fq%3Dhonda%2Bfuel%2Bpump%2Brelay%26gbv%3D2%26hl%3Den%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official%26sa%3DG A component that is "heat sensitive" is the sensors in the distributor and igniter in the distributor. Often the car may start fro cold and not restart when the engine is hot.
ANSWER by , April 18, 2010
I had a simular problem. Seemed to be worse in hot weather. Turned out to be the main relay. Under left side of dash by fuse box. Costs about $80.00. The fuel pump won't pump the adequate pressure to the fuel rail because the relay is not working. You might have noticed you don't hear thar whirring sound when you turn the switch on. The relay hasn't activated the fuel pump. Mimics a lot of other expensive problems. Good luck. P.S. I fought this problem for over a year then found the answer on a forum simular to this one.
COMMENT by , August 25, 2010
i have the same problem. so if my car runs for 15 minutes then shuts off and now only cranks thats it fule pump makes the sound but still doesnt start but turns over could it be the main relay
ANSWER by , January 06, 2011
we've had the same problem with a few hondas at the shop and it ended up being a problem in the distributor. they would start up fine, drive fine, but after you parked it and went to start 5 or 10 mins later it wouldn't start. try changing the distributor i bet that will solve your problem. It's obviously only happening when the components in the distributor are getting hot.
COMMENT by , December 21, 2014
I have a 1998 honda civic lx Starts fine when it's cold, but after driving for a while and I shut it off It will not start, I have to wait 30 min. I have replace plugs Distributor cap& rotor , map sensor, idle control valve & main relay, could it be the coil or the distributor????
COMMENT by , September 14, 2015
Check the coolent temperature sencer it's the single plug directly under the distributor,disconnect it and see if it starts