foundsheep

Got a 99 LX that is strugglin to start when the engine is warm/hot. For instance I drove 3 or 4 miles to Wal-mart going no faster than 45 with average speed of 30 and when I came back out it took me 3 attempts and some waiting to get to fire up.

Cold starts are a breeze.

I've seen that it could be a fuel related problem. Just wanted to see if anyone had some specific smarts on what it could be.

Thanks

blainoyo

AWWWW im having this problem also but with my 94 civic. Iv got spark and fuel. and i have a code 9 on my engine light . which is NO. 1 cylinder. and my car start with a breeze cold also.

lazlong

@ blainoyo: That sensor is in the distributor housing itself, the only way to change it is to change the housing.

@ foundsheep: Any codes?

teahou

Back when I was working in shop, we coined a phrase "Jap car syndrome", (at least I think we came up with it, I ain't never heard it anywhere else). Anyway for some reason, when 4 cylinder engines get driven a short way, shut off, and start again, sometimes the engine actually floods (excess gas) which washes the oil off the cylinder walls, which causes no/low compression and a 'crank, wont start' situation.

Near as we could tell, this occurred because when a car is cold, it shoots in more gas to keep it running and when you start, stop, start - it is sometimes too much for 4 cylinder cars. The usual handling we recommended was a tune up, based on the idea that a fresh tune up would produce a better spark, and therefore have a better chance at not flooding.

Oh, and the technique we used to start a car we suspected of having this issue was to hold the gas pedal to the floor while cranking, because doing this tells the injectors to shut off, which you want, otherwise you just continue to flood it.

Well, that's my story and I'm sticking to it.

blainoyo

@ lazlong, i replaced the distributor, rotor, and cap. and code 9 is gone. iv been researching on google and many ppl who have the same problem as me say its the EFI Main Relay. This makes sence because often when my car is hot and wont start, it sounds like it is almost catching but just wont start up, as if its not getting fuel.

@ teahou, i tried the pedal theory and it didnt work for me, i may have a diff problem

lazlong

You should hear the main relay click when you try to start the car, it's very audible. Look under the dash (may be behind the glovebox or kick panels) for the relay and test it.

To test:

1. Pull the relay

2. Apply battery voltage to terminal 85 and ground to terminal 86 (terminals 85 and 86 are interchangeable) . If it's not labeled look for the 2 smaller terminals. When you apply battery voltage and ground the relay should click. That's how you know it's good.

If it's bad, I've seen where people have taken them apart and soldered the connections back together.

blainoyo

around noon i went out to start my car, it is so hot in the car youd couldnt sit in it without sweating crazy, so i cranked it and it started right up. i took of the EFI main relay and all the solder points look fine but i resoldered every point. so i put the relay back, drive to the bank (10 mile drive) come out try to start my car and it doesnt start. i wait 3 min and retry, it barely starts. i drive to get gas (6 miles from bank) and try to start it again nothing, i crank the car 3 more times and nothing. wait 10 min, crank again for 2 seconds and them it barely starts up. this is driving me nuts.

NOTE: i checked and had fuel and spark at the gas station. and the fuel pump did turn on

blainoyo

ok i found the problem, its the IAC valve. so you were right about the idle. I think when it gets hot the electric motor on the IAC valve gets stuck or grounds out. The part is 266 bucks at my honda parts dealer so im going to try and clean it out with some brakes cleaner bc that is a hard hit to the wallet. found via google, http://www.honda-tech.com/showthread.php?t=1575913 Ill post again for and update

blainoyo

Is the main relay supposed to get hot when your car is on and your driving it?

lazlong

It'll get warm because of the electricity flowing thru it but, not too hot to touch.

blainoyo

ok you were right. my car has had the same problem still, and iv replaced the main relay and the problem still happened, i read this forum again and tried the pedel to the ground and it started right up after 2 seconds of the pedel on the ground. So for anyone else id try this and if it doesnt work its probably the main relay. the soldering goes bad after getting hot.

creakid1

Funny, when you said,
"@ lazlong, i replaced the distributor, rotor, and cap. and code 9 is gone. iv been researching on google and many ppl who have the same problem as me say its the EFI Main Relay. This makes sence because often when my car is hot and wont start, it sounds like it is almost catching but just wont start up, as if its not getting fuel."
I really think you were incorrect (assuming you have the same problems as mine). B/c when this happened, I kept smelling unburnt fuel!

Anyway, my '00 Civic DX hatch is parked out of town, & I will try this old-fashion "carburetor" method... I'm so surprised to know that "hold the gas pedal to the floor while cranking" "tells the injectors to shut off"!

Thanks teahou!

turbomikeg88

I also have this warm/hot start issue with my 99 civic ex, and i've replaced the distributor, main relay, plugs, wires, IAC valve, crank sensor, fuel pump, fuel filter, battery. I'm at the point in which I'm running out of ideas, any help will be appreciated.

lazlong

Bad main relay.

Louie Gomez

did the IAC do the trick? I am having the same issue on a 99 Civic.
Replaced main relay, ecu, distributer, fuel injectors, spark plugs, wires.

Tiffany

I know this is an old post but did you ever figure out the problem? I have also replaced the ect sensor with no luck.

Wankenstein

Could be an a failing/weak ignition coil (icm)?
Main relay solder joints may be a possibility as well.
There's many threads related to this issue...use the search bar above/right and type in the issue to search .

Shavo Canez

​​​​​​I have same problem, i changed the inyectors and no more problems