On really hot afternoons, engine will crank but won't start
 

Hi all. Some input is much appreciated, if you don't mind and thanks in advance for it.

I have a 99 V6 Accord Vtec with 83K miles, no mods other than a cold air intake. I've owned the car for 3 years now, but just this summer it has given me a repeated problem when trying to start it on a really hot day. It's not tried and true, though. It has started up fine on such days, as well. Most times, it will crank up and the engine will start, but no matter how much gas I give it, the engine will sputter at around 200-400 RPM then die. Then when I turn the key, the engine will turn fine, but it won't fully start... just keeps on turning. It's odd, because if I just leave the car alone for 10 minutes or so, it will crank up fine. I haven't gotten stranded anywhere yet, at least... it's always cranked eventually. Other times, when it didn't do the sputtering then die, I felt like I didn't keep the key turned in the ignition long enough on the first turn and when i try again, it gives me the issue.

I've checked the filter on my intake and it's perfectly clean. I even detached the filter and tried to start it, making sure air could get in, but with no luck.

I'm guessing that it's something to do with my ignition, but I also wonder whether it might be my fuel injector. I've noticed that my gas mileage has gone down quitea bit recently, but attributed that to my using the AC all the time.

Any thoughts??

RE: On really hot afternoons, engine will crank but won't start
 

There are a lot of posts on here about the main fuel relay (MFR) failing when it is hot in the cabin. The solder expands and contracts over time and will develop cracks. When the cabin is hot, the solder will not have a good connection.

When you turn your key to the on position (before you try to turn the engine over), there are several clicks from the MFR and the fuel pump will whirl for a few seconds (pressurize the system). You should try to listen for that noise when the car is starting properly. If you do not hear that sound when the car doesn't start, then the fuel pump is not getting power and not turning on.

Is the check engine light on? You can also take your car to AutoZone and have them scan the codes for free. This could also indicate some other problem with the car that might be causing your starting problem.

RE: On really hot afternoons, engine will crank but won't start
 

Some other ideas ..... though MFR is common and matches these symptoms.

1) Dirty injectors -- Injector cleaner with a quarter tank of gas. Don't fill until the gas light comes on.
2) Water in the gas -- Dry gas with a quarter tank of gas. Don't fill until the gas light comes on.
3) Dirty or water-logged fuel filter -- Change the filter

RE: On really hot afternoons, engine will crank but won't start
 

Sounds like the main relay to meeee..........
Do asearch for "main fuel relay" or "main relay" on this site. There should be adiy or something somewhere. You could either re-solder or replace with new......if the main relay is theproblem.

RE: On really hot afternoons, engine will crank but won't start
 

It's a 6th gen V6! Let's blame everything on the tranny!!!!!! j/k

I think everyone would agree that it's likely the relay until that can be ruled out.

RE: On really hot afternoons, engine will crank but won't start
 

You're right. It probably needs a new trans too

RE: On really hot afternoons, engine will crank but won't start
 

when engine cranks and does not start try this ...

https://www.hondaaccordforum.com/NO_...m_17302/tm.htm

RE: On really hot afternoons, engine will crank but won't start
 

BAMM!!!!!!

DH is johnny on the spot with the testing and repair!!!!!

RE: On really hot afternoons, engine will crank but won't start
 

dh must be bored or something. he's spoon-feeding again

RE: On really hot afternoons, engine will crank but won't start
 

:D

Thanks y'all for the feedback. I'll check on the MFR. [8D]