| Fireblade6 |
My wife has informed me once she was at full stop, the MDX engine just turned off abruptly with no indications prior or after that "check engine." light is on.
Just this morning, she rushed off to the store and at a stop sign, the MDX engine cut out again.
Has anyone experienced this and if so, what can be the root of the problem? Please advise. Thanks! |
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| renov8r |
Not much to go on...
If there is NO CODE stored it becomes a very unpleasant huntin' trip.
Obvious candidates are the AIR IDLE CONTROL unit. There is a pintle that adjusts to allow sufficient air-flow at idle to keep the vehicle running. These can get dirty/fail. They also need to be reset after loss of electrical power/battery removal as the base line settings are 'learned' into volatile memory in PCM.
I've seen FI vehicles that are very sensitive to loose fuel filler caps/ evaporative canister operation. Something gets jiggled a bit and wham it is dies.
Other candidates include FUEL PRESSURE REGULATOR, which has a vacuum line. If there is leak in the vacuum line, it MAY result in fuel pressure being so low as to stall at idle when vacuum us typically highest.(though typically these are setup to "push pressure up" with loss of vacuum, so performance is greater at WOT)
Similary the whole FUEL PUMP & FUEL DELIVERY system should be gone through. Wierd things like a stuck control valve can result in odd behavior at idle, with the fuel pump unable to self regulate flow at idle, but it'll be fine off idle, when vacuum is lower and flow is higher.
Even an electrical gremlin COULD exhibit such behavior, as typically alternator output is lowest at idle, and marginal problems disappear at higher output.
If you are lucky the OBD has stored the condition and it will be quickly corrected. Even it is not stored, it is highly unlikely that this is a "major defect" though diagnosis could be time consuming...
Good Luck, let us know how it comes out! |
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| jonnygoodboy |
| ...but I had the engine shut off at a light once before, too. I'm not sure, but I think I had been driving about 1 mile with the parking brake on:3:. I wonder if there's a safety shutoff feature? Sorry I don't remember more about the incident. |
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| DaleB |
Also possible it's one of the above but exacerbated by temperature especially if it's electrical.
Is this happening before the engine is fully warmed up? Mornings are cooler now too. These are all the things that need to be considered when you tell the tech what is happening. |
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| frostyra |
| It might be water in your fuel. I had the stalling happen twice on the same tank of gas in my MDX, but never again. On my Explorer, I got two tanks of gas that had so much water in them, that even DryGas wouldn't fully cure the problem; I just had to run the tanks almost dry before refilling (at a different station!). |
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| Fireblade6 |
Frostrya-
You know what you may have a point there....DAMNIT! Ugh!!! So how do I get rid of the water in my gas??? |
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| frostyra |
| Easiest way is to pour a can of DryGas (that's its brand name) into a FULL tank of gas, and drive 'til it's nearly empty. Just don't use more than one can per tankful. You should be able to find it at most auto parts stores. DryGas is alcohol (methyl, perhaps?), which absorbs water and renders it harmless/burnable. At least there won't be slugs of water going through your fuel injectors. |
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| edepa |
quote:
Originally posted by Fireblade6
My wife has informed me once she was at full stop, the MDX engine just turned off abruptly with no indications prior or after that "check engine." light is on.
Just this morning, she rushed off to the store and at a stop sign, the MDX engine cut out again.
Has anyone experienced this and if so, what can be the root of the problem? Please advise. Thanks!
Could be almost anything causing a stall. I had an mb ml320 that stalled once or twice on my wife. but restarted fine. then it stalled on me near my regular mechanic's shop. he said he found no spark to plugs, to call mb since it is a warranty item. then...mysteriously...it finally started! drove home and then had mb flatbed it to their shop. they said it was caused by...listen up here...the keys! I thought they were nuts, but the keys have an imbedded chip that communicates with vehicle as part of security system. I was sure they were full of it...but they went and changed it and assured me it was now fine. On a trip from ny to d.c. i stalled at toll booth at end of jersey turnpike, in backed up traffic. MB customer service finally got me out of there on a flatbed to a dealer in delaware...who thought it was fuel pump. gave me a nice mercedes loaner and off i went...on my return they said there mechanic has stalled AFTER the fuel pump was changed...and they needed to keep it to look at and fix. The upshot???? the onboard computer was shot, and apparently it was messing up on engine timing signal off sender which i assume is on flywheel somewhere. once it was replaced, the ml was fine and never stalled after that. well, hope you find your problem, and it is not as mysterious. :( |
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| reedg |
I had this happen when I had a Lexus ES300.
At the time it had 80,000 on it, out of warranty.
I took it to a Lexus dealership, they replaced the transmission no questions asked for free. I didn't get an explanation, didn't need on.
Oh-I paid for the labor. |
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| master_tech |
Hi,
I too have run into this problem on my MDX. So far, the problem has not returned.
What I did was ;
removed the throttle body
cleaned the throttle body bore before and after the throttle plate
(throttle body was "gummed" up)
remove and inspect the idle air control valve (iacv) see if it is dirty
( i replaced my iacv since it was off )
reinstall the iacv and the throttle body
with a scan tool reset ecm/pcm
perform an idle learn
If your not familiar with cars or just don't have the tools, have a qualified mechanic do the task. Good Luck and I hope this helps! |
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