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Start and then Stall -- '04 EX-L 4wd

1686 Views 77 Replies 10 Participants Last post by  undivide
This happened after the spouse returned from grocery shopping with a mixed highway + local driving: the car struggled to start, and after it started, it stalled immediately. There was some notable vibration from the engine bay before it stalled. For the first 2 tries, it left a strong gasoline odor. After a 3rd start, I pumped gas for a min or so and the car got into the normal working state. Once in this state, everything worked fine and I drove the car on the road without issue. It even stopped at STOP signs and traffic lights without stalling or abnormal vibration.


[Update 1]: After turning on/off a few times, the symptom is now repeatable: if right foot rests on brake, the car cranks strong but it won’t start; if/when cranking the car and at the same time pumping gas (ie right foot not on brake pedal), the car can start -- is the foot not on brake a sign that something went bad? Once started and pumped gas for a few seconds, the car drives just fine – it doesn’t stall in subsequent stops at STOP signs or at red lights.

[Update 2]: When the hard-to-start-then-stall occurred, there was no CEL or any warning light on the instrument panel initially. After many on/off tries, now the engine light and VTM-4 light are on.

Vehicle repair history: it’s a 2004 EX-L, 4WD with 203K miles:
- Starter and alternator are still original
- spark plugs were replaced with NGK at 152K miles in 2017
- EGR valve was replaced in 2017 at 155K miles
- timing belt and water pump n all belts are replaced at 157K miles in 2017
- diff fluid changed in 2019 at 172K
- 2 O2 sensors (the ‘04 EXL only has 2 O2 sensors) were replaced in 2018 at 164K miles
- valve adjustment done & PCV replaced in 2021 at 189K mile
- The battery was replaced in Nov, 2022 and is practically new

I searched and the past working fixes include: valve adjustment; fixing timing belt jump one tooth. Neither seems the cause of the problem I am experience.

Where do I look next?
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Rocky good advice, but never check or re-gap iridium plugs. You don't even want to touch them. Visual inspection is advised. A gap issue can happen if the plugs were dropped into the spark plug tubes. Otherwise gap shouldn't be an issue. Another thing to check with the spark plugs is that they are NGK or Denso. Nothing else should be in our engines. Plugs should be bought from a reputable source, not Ebay or Amazon, or other sketchy website.
 

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Rocky do you drive short trips? The cats fail if they don't get up to operating temperature. They only work hot. If you live in an area that doesn't have high speed roads like freeways or highways, that would explain your failed cats. Otherwise they can survive the life of the vehicle under the right conditions, or last years if they never actually get to operate.
 

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newer Honda engines don't have this as the drive-by-wire throttle body controls the idle.
might try cleaning this part first and see if vehicle operates any better then probably replace it for a longer more permanent solution
 

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newer Honda engines don't have this as the drive-by-wire throttle body controls the idle.
might try cleaning this part first and see if vehicle operates any better then probably replace it for a longer more permanent solution
There is a cable. It goes to a box on the passenger side firewall up top. You will see a black cover and 2 or 3 bolts I forget how many holding it on. Remove the cover and you will see the cable. Then wires go to the Throttle Body from there.
 

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Thought you were talking about the newer vs older 1st generation. Not newer generations. I also thought I was responding to the question about cable slack in another post. Just realized this is a completely different thread, so your post made different sense to me, and was a little confusing trying to figure out what you were even saying in your post. lol. It all makes sense now.
 

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Discussion Starter · #28 ·
Make sure they are tight. Check all of your ground cables and make sure they are all secured. Look for corrosion, cuts, kinks, etc... If they all look good next is to check they are good.
Do you have a DMM? You can check for voltage drop. Place one lead on the positive terminal, and get a voltage check before starting. Once you have the battery voltage start checking all of the ground locations for voltage. It should stay the same. This includes checking ground on the vehicles body, the engine, or anywhere else you see metal. If that is all good. Have someone crank the car and check voltage while cranking. It can drop a little, but you don't want it to drop bellow about 10 volts.
I am with you about the reasoning that the problem is unlikely an individual cyl (thus less likely a plug or coil problem). IAC valve is plausible as it affects all cyls, so are wire connections or the healthiness of the battery, or fuel line problem.

A few thoughts wrt battery, cable and wire connection:
1) the battery was bought in Costco. It's their Interstate line and the last one I bought lasted 6 years. It was installed by me and the connections look good to me. The terminals are clean.
2) The ground cable connecting to a place underneath the starter is rusty and should be replaced any way.

There is one missing link: the car can start immediately when cold, but it struggles to start and then stall when it's warm. A wire connection problem cannot explain why the engine temperature plays a role here.
 

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easy, when the vehicle is cold it's going into higher idle full rich mode to help warm up the engine faster. with engine warm its going to go into its default low idle mode with normal semi-lean fuel mixture. still putting money on the IACV.
electrical problems would show up during other operating conditions
 

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Discussion Starter · #32 ·
Yes, misfires at cyl 1 4 5 6 are reported consistently and repeatable.
easy, when the vehicle is cold it's going into higher idle full rich mode to help warm up the engine faster. with engine warm its going to go into its default low idle mode with normal semi-lean fuel mixture. still putting money on the IACV.
electrical problems would show up during other operating conditions
Alright, the plan of attack:
1. Take the IAC valve off the throttle body and do a thorough cleaning. If needed, replace it with a new one, but i will do a cleaning first. It's never done and it's due regardless.
2. Pull plugs from cyl 4 5 6 and 1 and do a visual inspection of plugs and coils first and take from there.

The piloteer community is amazing and I'd like to thank everyone in this thread for your suggestions and camaraderie!
 

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wonder why cylinders 2 and 3 are not showing misfires, maybe its just not happening often enough to trigger the code and its just in pending state?
 

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Where are you getting fuel smell from? The fuel enters the rails from the 3rd injector site. Another hose feeds the front rail. I wonder if it is reaching cylinder 2 and 3 and losing pressure by cylinder 1, and losing pressure on its way to 4, 5, 6. If you smell fuel in the engine bay, that isn't right. The exhaust yes, but the engine bay, no.
 

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Discussion Starter · #37 ·
Well, IAC malfunctioning is a hypothesis, not a fact yet. I don't have an explanation why cyl#1 4 5 6 misfired, but not 2 and 3.

I pulled out the coils and plugs for cyl#4 5 6 and the #4 is soaked with oil while #5 and #6 are bone dry! Seems that I have leaky valve gasket!

In mid 2021, I was adjusting valve lash and replaced only the front valve cover with (1/2 of) the felpro set; the back bank was very much pliable and I decided to not change it. That was only 14K miles ago!

Damn Felpro! For all fellow piloteers: if you adjust valve lash, do yourself a favor and get the OEM valve cover gasket!

Anything else to fix when oil getting into the plug well? and how to clean up the oil in the #4 well?
Wood Font Symbol Cross Rectangle
 

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Time to pull the spark plugs and inspect both plugs and coils. Reverify the plugs are correct type, condition and gap. Any signs of burning, arcing or damage to coils? Replace as necessary.
And retorque to spec (see attachment). Our spark plugs sometimes have a tendency to loosen and even back out. Not too sure about applying the anti-seize, though.



2) The ground cable connecting to a place underneath the starter is rusty and should be replaced any way.
Yeah, check them all, then (see attached diagram). You can replace some iffy ones with these good EverStart alternatives from Walmart, no kidding.

Hand tool Pliers Tool Motor vehicle Metalworking hand tool


Liquid Gadget Audio equipment Street light Font
 

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... but never check or re-gap iridium plugs.
For what it's worth - this is interesting. I thought about this when I replaced mine at time of TB job (stealership wanted $600 to replace plugs, whatta f'in joke). I've been gapping plugs since I was a kid and I just couldn't bring myself not to check my new NGKs before putting them in. I did check them with feeler gauge and if I remember correctly they were all pretty good out of the box. No issues since replacement which has now been over 2 years and 25,000 miles.
 
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