Hi All-

New to the forum so I hope someone here has the answer. I own a 2001 Grand Caravan EX that my wife primarily drives. It has been maintained regularly and now has 140k miles on it. I just replaced the water pump (it was weeping) and serp. belt. No issues there but about 5 days later the van stalled while she was on her way to work. She was stopped at a light and noticed that it idled a little rough (sputtered) then quit. She restarted it and continued on her way but said that it seemed sluggish. The odd thing that I found was that she didn't see any dash lights/alarms at all when it stalled or after she restarted. She drove it home after work and along the way- only then did the check engine light came on. I checked the codes and got p0172 (1/1 fuel system rich) and p1684 (battery was disconnected). This combination perplexes me as the battery has not been disconnected since it was replaced about 2 years ago. Cables are not corroded or loose.

Any thoughts on where to look or what could throw this combination of codes? Typical issues to look into? Tests to rule out possibilities?

I would like to narrow down the culprit and avoid just replacing sensors as a method of chasing down the issue.


Perplexed

 

Try these out:

http://www.obd-codes.com/p0172

http://www.obd-codes.com/forums/view...php?f=1&t=5357

 

Hi-

Thanks for the links. I did poke around and noticed similar threads. The battery connections are good,clean, & tight. After reading some of the threads I wonder if the alternator could be the culprit or fuel pump or relay? The Alt. was replaced early on under warranty because the lights flickered. I believe it has an internal regulator and assume that if it goes bad the battery would carry the remainder until it drained vs. stalling and restarting. The fuel pump/pump relay sounds plausible. I don't hear the pump whine that is typical with a bad pump and assume a relay just goes when it breaks. The symptom is just plain weird.

My plan of action is to check all the electrical connections to starter, etc. Test the Alt. with a volt-meter (not sure what numbers I should see as normal). Clear codes, and drive to see if I happens again.

Stay tuned...

 

UPDATE- inspected all connections; they are tight, clean, and corrosion free. Alternator was putting out around 14v (low 13.96v, high 14.10v). The meter was pretty much hopping numbers around in that range- not sure if that is an idication of anything or if normal behavior.

I will clear the codes tomorrow. I don't have a OBDII scanner with me so will have to run buy an auto store and have them clear it.

 

Check the rear bolts on the exhaust manifold, That would cause a rich code. If you were leaking exhaust.

 

OK, so everything checks out. Check engine light went out on it's own when driving it yesterday but I also cleared codes by disconnecting the battery. Took it out for a road test today and performed w/o issues. I did notice the idle drop to 600 RPMs when at a stop light. Not sure if that is any indication or normal. I don't drive it often so I can't say if that has always been the case or not.

 

BTW - The P1684 code is termed an "information code". It will not turn on the CE light. Many consider it a nuisance code because it will often appear with no consequences. I've seen it several times on my van and others when nothing was done to induce it and everything is working just fine. The P0172 code is the one you need to pay attention to. Looks like it cleared for now. The engine was either getting too much fuel or not enough air.

 

All items suggested check out fine. I was able to connect an OBD scanner mainly because I wanted to see the O2, idle, TPS, and MAF #s. Only thing I found interesting was that In gear, the idle dropped down between 675 - 680 and in park, around 845. If I tap the peddle than it will bounce up to 750 range for a bit. Can anyone tell me if these are normal numbers and if not, how do you adjust the idle? I know there is a stop screw but understand that you can't mess with it too much else it will throw off codes as the computer tries to compensate. <shrug> ??? At this point, I feel like I'm chasing ghosts and will have to wait until a hard failure.