Do you hear the fuel pump run? If main relay issue I think you lose the fuel pump.

Does the green key come on then go out after a couple seconds? Prove the immobilizer is not the issue.

Is it only when it's cold and if so does it rev up a bit when it does start? It should idle up over 1k when first started then slowly drop down. A IAC sticking closed will make for no rev up and hard starts. If it starts right up with a bit of throttle this may be your issue.

 

I'm not sure if the pic made it so i pasted again.

It hard to hear if there is any noise from the pump with all the cranking.
The cranking drowns out other noises.

I'll listen harder and check the green key.
But it does start.
Just takes about 10 seconds of cranking.
So the fuel pump is working.

 

It hard to hear if there is any noise from the pump with all the cranking.
The cranking drowns out other noises.

Turn the ignition key just to ON. You should hear the fuel pump run for two seconds.

If you hear it, you know the relay and the FP are good. If not, it could be the relay or the FP. However, the main relay is more likely to fail than the fuel pump.

Dave

 

Yeah, that's it. Takes some prying to get it out, too.

 

Photobucket is the worst service ever. Just upload your pics here as an attachment.

 

Testing the upload function

 

It is not starting today . . . just cranking.
It was able to start yesterday after the third try.
I'll try again tonight.

I can hear the fuel pump

 

Did you try starting it with the accelerator pushed down a bit like I mentioned? It has been very humid and rainy in the Northeast lately, more air into the engine may help especially if the IAC is sticking. It's an easy thing to try when it doesn't start or is slow to start.

 

Your pic IS of the main relay.

It's actually good that your intermittent problem is now constant. That should make it easier to find.

It would help if you observe exactly what the green key light does when you take the key out, and then when you put it in and turn the key to ON (before starting).

Also good to hear that you hear the fuel pump run.

This thread I started, and in particular a post with an annotated circuit diagram may help in the understanding of how the main relay, fuel pump, and immobilizer system all interact.
http://www.odyclub.com/forums/24-19...dyssey/294105-immobilizer-flakiness-my-99-ex-voltage-related-2.html#post1792233

Even with the service manual, there are some things that are not exactly specified, which I discovered through experimentation there and reported in that thread. BTW, for me, no real repair was ever done, and the car has been running flawlessly for many months now. My problem (that was confirmed to be a immobilizer issue) just went away.

Other suspects to keep in mind: ignition switch, fuses (as shown on the circuit diagram)

 

Thanks Olkskewel. I'll read your post/research tonight.

My car just started after after an extended cranking period. . . maybe 10 seconds.
So can I rule out the fuel pump since it is pumping well now ?

 

In my opinion you can almost rule out the fuel pump just because it is a Honda Odyssey. Really, I don't think these fuel pumps ever go bad. People might replace them, but not necessarily because the pump failed. I've got a brand new one in my garage that I bought because I mistakenly believed I needed to buy the full assembly just to get the fuel level sender (float thing attached to the pump). Not even really trying to sell it because I know nobody will probably really need it. But hey, if anyone wants to send me an offer ...

I'd focus on the green key light, quickly check all those fuses, and then possibly the main relay. (I'd rank all those above an actual fuel pump failure of any sort)

If it's back to intermittent, there may be a chance of a flaky connection in the relay. If you have a soldering iron, it is very easy to pop the relay out, visually inspect the solder joints and re-flow as needed. And if you've got a few electrical tools and convenient 12V power source (I use a cordless power tool battery for this), you can do a very careful bench test of the main relay to convince yourself it is rock solid ... or not. That's what I did.

 

When my girlfriend's Accord had its first engine startup problem, I went with the odds and just replaced the main relay. The engine started first time, every time after that.

The main relay is inexpensive to buy and easy to install. It's much less hassle than running out on even one rescue/repair mission.

I'm not saying that the main relay is always the problem, but it is a common point of failure on Honda's. If it had not fixed the problem on the Accord, at least I would have known what it wasn't. (BTW, bought the OEM part.)

Dave

 

Thank you all for your comments.

oldskewel: Great post on the immobilizer. It looks like if the computer doesn't "think" you have the correct key . . . or a damaged key . . . it will shut down the fuel system so the car won't start. It will crank . . . but not start. And if you have another key nearby with a chip in it . .. it can get confused and enable the immobilizer. I'll keep a close eye on the green light.

OdyinNH: While it's been cranking . . . I've been pushing the accelerator.

davesdrivesody: Thanks for the tip. I'll get a new main relay. For what I've read on this site, it seems like just a normal part of maintanence with Odysseys. Even if it doesn't solve this issue . . . I'm sure it will prevent a future issue. Is there a screw holding the assembly ? Or do I just wiggle the little black box off it's bracket ? I'll get a new one rather than solder the existing one since I don't have a soldering gun

 

Is there a screw holding the assembly?

You have three choices to remove the relay:

1. Wiggle it off the bracket. It's a very tight fit, like OdyinNH mentioned above. Also it has a one-way wedge tab molded into the case that secures it to the bracket. You have to override the tab so it will slide off the bracket. Look at the new one and you will see what I mean.
2. Remove the single bolt that attaches the relay and its bracket to the van then remove the assembly. Requires a bit more dexterity, but it's easier to swap the relay on your bench than under the dash.
3. Leave the relay housing in place and slide the workings out of it. You just need to pry the two long sides of the housing outward a bit to clear the locking tabs. Again, have a look at the new one and you will see what I mean.

I used #2. I found #3 after; I would give that a try next time.

Dave

 

In order of above:
-Another key should not confuse the immobilizer, all it cares is that there is a good key. Watch the green key dash light and make sure it reacts as it should when the issue arises but I'm doubtful of that for the issue because you say it sometimes starts after a few cranks. Unless of course you turn the key all the way back before trying again.

-Ok, 1/3 to halfway is plenty of pedal but sounds like this is not helping.

-The relay just wiggles out but it is in there solidly.

Curious, when you say it started reluctantly, can you describe that? As in sounds like it starts like it was flooded or something else?

 

.

Curious, when you say it started reluctantly, can you describe that? As in sounds like it starts like it was flooded or something else?

Hi OdyinNH. That's a good description. It actually sounds like it flooded . . . like it's choking. Then it gets just the right amount of air and then turns over. But I think this sound is the same sound for the opposite. That is . . . when it is starved of gas. So I guess a better description is that is
"choking".

 

#3 for the win!

 

Now that Dave mentions it, I think I did #3 too. Mine looked perfect inside.

As for the starting, I wonder if the car is flooding, leaky injector or something. Next time it won't start put the pedal to the floor which opens the air path completely and limits/stops fuel flow.

 

The IACV is an automatically controlled valve that lets a precise amount of air in to maintain idle speed, WHEN THE THROTTLE PLATE IS CLOSED (i.e., foot is off the gas).

When your foot is on the gas, even a little, as you mention you have been doing following other good advice above, the IACV is basically bypassed. The engine will get any air it needs through the part-open throttle, and the IACV may add air on top of this (making for surging, or other weird things if the IACV malfunctions) but should not be preventing your car from starting.

IACV cleaning is definitely something that is commonly needed on these cars, and anything you do there will probably be helpful (just as replacing the main relay was), but I would not expect it to solve this problem. There should be plenty of other threads with details on the cleaning on this site.

Briefly, at least on my '99, I needed to remove the throttle body to get the IACV off, and was able to clean it using q-tips, brake cleaner, and patience, without opening it up ... until the last time I cleaned it when this would no longer get it sufficiently clean. That last time, not having the 5-pointed screwdriver needed for those screws, I used a Dremel tool to cut slots in the tops and used a slotted screwdriver. BTW, in removing the throttle body, you'll find instructions that say the paper gasket has to be replaced. The first time I did that, it was true - the paper was bonded and ripped and needed replacement. Since then (twice, I think), the gasket has not needed replacement, but I keep a spare on hand just in case.

So I don't want to slow you down on the IACV. Do it. Do it well. Have fun at it. It will be good for your car. But don't be disappointed if it does not really solve your problem today.

 

Thanks odskewel. I like a good problem. This is not my primary car so I have plenty of time to figure it out.
I'll do the IACV another time.
Something will eventually present itself and lead me to the solution.
I'll post back if I find something.

 

Hi Guys. I'm just giving this thread some closure.
It ended up being a blown head gasket.
There was coolant in the cylinders.
Once it started . . . it ran great.
But getting it started was the issue.

Thanks again for all your patience and support.
Joe

 

Oh man, tough break!

Some heavy wrenching ahead...

Dave

 

Thanks for this thread! I was able to locate and repair my main relay today in about 20 minutes. Found a broken solder joint for the fuel pump

 

I know this is an old thread but just curious how this ended uo being a "bad head gasket" if no overheating at any point was involved. This is a 1st for me to hear as 99% were either the Main relay or FP.

 

Head gaskets do fail sometimes with no overheating. I had a 09 Toyota Matrix(same as a Corolla) that came in with misfires on 2 cylinders. Turned out the head gasket blew between the cylinders. No overheating and no coolant loss. Pulled the head and had it checked at a machine shop. It was perfectly flat. Lightly sanded the head surface and the deck surface, replaced the head gasket, and put it back together. Ran perfect.

 

Wow that's crazy, mostly good but just that minor crack would render it useless... but yeah your car had misfires but the ops doesn't nor are symptoms of stalling then running fine after few mins that of a bad head gasket.