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Hard start on hot start in my '02 Accord, along with other irritating symptoms

Hey friends,

After 10 years of regular scheduled maintenance, my fairly uneventful relationship with my car has taken a nasty turn. Here’s the main problem I’m experiencing:

Sometimes, on hot and sunny days (or any time I’m in Washington, DC) if I park my car for 15 minutes or longer after having driven it for five minutes or more, when I return to the vehicle, it will fail to start. Sometimes I’m able to give it some gas when it’s in neutral and I can get it going, but the engine will ping and threaten to stall out until I’ve driven it a few blocks. Once I get her going, she runs like new.

In addition to this problem, my AC has been a bit on the fritz. Driving in stop-and-go traffic when it’s very hot outside, the vents will only blow hot air. Once I get the car up to a good clip (30mph or so), it kicks back in.

To top it all off, as of about a week ago my tape deck periodically loses power. Sometimes it will display a “TAPE ERR” message; usually it just fails to respond to any input and won’t eject.

I’m guessing that at least two of these problems are connected to each other. A little internet research revealed that this might be a problem with the main fuel relay. Does this sound about right? Could the other two glitches be related to the engine problem?

Any help is much appreciated!

You have three different problems, they are not related. The fuel pump relay could be the cause of the no start problem, but in your case, it doesn’t really sound like it. I don’t quite understand the second sentence, running poorly and not starting are two different issues. When does the poor running occur?

The AC issue is probably because the heater control valve in the rubber heater hose next to the firewall under the hood is not closing completely. Our 97 accord has this problem as does my son’s friend’s 02 Accord. You can manually close it and the AC will work better.

The tape err is in the radio itself, it has nothing to do with your other issues. Use the CD instead.

That no start, poor running thing could be the main FI relay but I’m more inclined to think it is a leaky injector, flooding your engine if you let it sit for a while.
If you just leave it for a minute or two, does it start right up? It doesn’t start if you leave it for any extended period, I take it:?

Do you drive a V6? I have the same problem (hard to start engine when very hot) with an '00 Accord V6. It seems to happen at the turn of the seasons with the different grades of gas that are used.

The hard starting rough running problem when hot might be caused from vapor lock. This occurs if the engine is shut off hot and the residual fuel pressure bleeds off immediately. The fuel in the fuel rails starts to boil which causes vapor lock. Have someone test the fuel pressure to see if the residual fuel pressure is within specs.

The AC problem might be caused from a defective expansion valve in the AC system. The expansion valve is what controls the AC system pressures depending how fast the compressor is rotating. So when driving at speed with the compressor rotating faster the expansion valve opens slightly to keep the pressure constant. When slowing down or when stopped where the compressor is rotating slower, the expansion valve closes slightly to keep pressure constant. If the expansion valve is stuck open when the compressor is rotating slower, the system pressure falls off and the AC no longer cools.

Tester

Thanks for all the helpful replies, folks. Let me address some of your questions:

keith wrote:

I don't quite understand the second sentence, running poorly and not starting are two different issues. When does the poor running occur?

Most of the time, I can start my car without any trouble; when I drive on hot days, if I drive a distance and then park the car for more than 5 or 10 minutes, the car will hard start. When the hard start problem presents, I can usually rev the engine to get the car running, but it will shudder and the engine sometimes pings and I have to drive it for a few minutes before it returns to normal. Once this happens, the problem won’t recur until after I’ve left the car parked again for more than 5 or 10 minutes.

RemcoW wrote:

If you just leave it for a minute or two, does it start right up? It doesn't start if you leave it for any extended period, I take it:?

The car will usually start up right away if I drive and then park it for a short period of time (filling up the tank, for example). If I park for a longer period of time on a hot day, I run the risk of a hard start. If I leave the car for an hour or more (going to work, for example) the car starts without issue.

CGNC wrote:

Do you drive a V6? I have the same problem (hard to start engine when very hot) with an '00 Accord V6. It seems to happen at the turn of the seasons with the different grades of gas that are used.

Yeah, it’s a V6. When I first reported the issue to Honda the technician suspected the problem was caused by vapor lock resulting from gas vendors switching from winter to summer petrol. I’ve experimented with different gas providers and the issue doesn’t seem to be related to what I put in the tank.

I had to schedule a service anyway, so I’m having Honda examine the problem. The check engine light finally came on, so hopefully they’ll be able to diagnose and fix the problem quickly. I’ll keep you guys posted.

Thanks again!

The car will usually start up right away if I drive and then park it for a short period of time (filling up the tank, for example). If I park for a longer period of time on a hot day, I run the risk of a hard start. If I leave the car for an hour or more (going to work, for example) the car starts without issue.

So it doesn’t like to start if you leave it for longer than a couple of minutes but less than an hour?

That sounds like a leaky injector to me:
If you leave it just for a couple of minutes, very little gas gets leaked so the cylinder isn’t flooded yet and it will start.
Then, if you leave it long enough for it to flood one of the cylinders, it becomes hard to start.
If you then leave it yet even longer for the fuel pressure to drop so the flooding stops and the gas in the cylinder to evaporate, it starts normally again.

Have you tried one of the better injector cleaners? It could fix your problem for just adding a $10 bottle to whatever is in your tank.

When it is indeed hard to start but you can get it going, do you see any particular color smoke come out of your exhaust?

I haven’t tried any injector cleaner; I didn’t even know that it exists. I’m (thankfully) new to real car problems and don’t have any mechanics in the family who would know about such things. I have not noticed any smoke at all; I’ve started up with acquaintances standing by who probably would have alerted me to any strange clouds. What would that indicate?

If you don’t see any smoke, you’re okay. After it has been sitting for a while, you may see some white smoke that eventually disappears but that’s likely just watervapor.

Chevron Techron or STP injector cleaner seems to work well for me. It is about $10 a bottle and you add it to your fuel tank. It is worth a try.

I have to agree with RemcoW on this, except I would only recommend the Chevron Techron, I think it is the better of the two. Post the actual code from the code reader. If it is a P030x with x being a number from 1 to 6, that will tell you which injector is leaking. The odds are that the injector will have to be replaced, but the Techron is worth the shot.

It turns out the only codes were for multiple cylinder misfires, so Honda technicians think I “got some bad gas” that’s still in my system. I’ve driven 2000+ miles since this problem started; does this sound like a legit possibility?

They also recommended refilling from zero with premium and using a fuel additive, which I know nothing about. Suggestions?

Thanks again for all the help, guys!

“Bad gas” is usually something said when mechanics are clueless.
Try the Techron additive. It may very well fix your issue. Hope it works out for you.

Report back either way. We don’t hear feedback too often and it may help someone else.

Yeah, my BS metre went off when I heard that, too. The problem did start right after I refueled from empty, but it seems like a coincidence. I’ll try the Techron and report back.

Quick update: the problem persists even after using fuel additive (the guy at NAPA suggested Seafoam) and switching to premium. I’ll be taking the car to a different Honda service centre tomorrow.

Update: replaced my main fuel injector relay with no luck (though the car is a little zippier when it does run).