Engine shutting down at stop light?

[Chuck1986]

So today I'm driving home and every time I came to a stop, the RPMs would bog down and the engine would completely shut off, without warning. I'd have to re-start the car and once I got moving, everything ran just fine. Then as I pull into my driveway (going about 10 mph), the engine again shuts down and I lose power steering and power brakes...the accessories (radio, gauges) all worked fine though.

So I pop the hood and I noticed that the intake hose was COMPLETELY disconnected from the throttle body. (Stupid defective clamps!). I pulled some codes for P0171 and P0174 (running lean) and P0300 (random/multiple misfires). Battery voltage is fine.

My question is, was the disconnected air hose the cause of this problem? Before taking the car for a little test drive I just want to see if this scenario makes sense, as I do not want to get stranded. My theory is that the engine shut down to protect the engine from detonation caused by running lean since the unmetered air flow was out of sync with the mass air flow sensor's reading.

Thanks for any help!

 

[mechjames]

I've run my explorer with the air tube disconnected from the throttle body once. Since it has a Mass air flow sensor in the air intake tube, it didn't run right at all.

 

[hate2work]

Has the car recently backfired? That can knock a hose off if not connected tight.

 

[Chuck1986]

Originally Posted By: hate2work

Has the car recently backfired? That can knock a hose off if not connected tight.



No, it was just some really defective hose clamps which have since been replaced.

I bit the bullet and went on a short drive around the neighborhood and all was fine.

Think it's good to go now?

 

[gathermewool]

Re-clamp and you should be good to go.

 

[mechtech2]

Not only a backfire, but engine movement relative to the intake may twist it loose.
Everything should be fine now.
But there is a possibility of the computer having to relearn things. That intake may have been leaking a bit before it came all the way off. The idle may seem odd for a few days, until the computer relearns it's parameters..

 

[Trav]

Yes the hose being disconnected from the throttle body could cause those trouble codes on many modern engines.

 

[UNC017]

Running unfiltered air may have gunked up the idle air speed control motor, which could cause the stalling upon coming to a stop.