P0443 and Low Idle
06-14-2011, 03:27 PM
#1
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Join Date: Feb 2011
Posts: 142
P0443 and Low Idle
Just fixed my EGR Flow code...using marktab's very helpful picture thread. It wasn't as awful as I expected...but it was definitely plugged. Got everything back together, and the EGR flow code went away, but now I've got another: P0443.
Also, it idles very low now...right around 500 when stopped and in Drive. Park is more like 650-700. If I start it cold, I have to lightly hit the gas for a few seconds because it idles too low to keep itself running. After about 5-10 seconds of warming up, it's fine.
When I let off the gas doing slower speeds (30 or less), the tach immediately drops to about 500 as well...it's like it's kicking into OD at speeds that it really shouldn't (If I press the O/D Off button, the RPMs pick back up). Anything from 35-40 up, it acts normal. When coming to or when I'm at a stop, it'll drop to 500 or even just below.
It always seems like it's going to stall when I'm stopping, but hasn't yet (other than when I've first started it).
Runs smoothly, just seems to idle too low--and there's absolutely no lack of power. P0443 is the only code.
Any ideas? Maybe some sort of vacuum line that I messed up in the EGR project? I don't see anything obvious...
Thanks!
Guess I'll add this info, too: It's a 95 SE Auto with 223K Miles
Also, it idles very low now...right around 500 when stopped and in Drive. Park is more like 650-700. If I start it cold, I have to lightly hit the gas for a few seconds because it idles too low to keep itself running. After about 5-10 seconds of warming up, it's fine.
When I let off the gas doing slower speeds (30 or less), the tach immediately drops to about 500 as well...it's like it's kicking into OD at speeds that it really shouldn't (If I press the O/D Off button, the RPMs pick back up). Anything from 35-40 up, it acts normal. When coming to or when I'm at a stop, it'll drop to 500 or even just below.
It always seems like it's going to stall when I'm stopping, but hasn't yet (other than when I've first started it).
Runs smoothly, just seems to idle too low--and there's absolutely no lack of power. P0443 is the only code.
Any ideas? Maybe some sort of vacuum line that I messed up in the EGR project? I don't see anything obvious...
Thanks!
Guess I'll add this info, too: It's a 95 SE Auto with 223K Miles
Last edited by jas1203; 06-14-2011 at 03:31 PM.
06-14-2011, 05:04 PM
#2
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Join Date: Feb 2011
Posts: 142
Okay,
Cleared the computer's codes again and started it with the AC on high and headlights on, to give it a load. My thought process is that maybe it sort of relearns something when you clear the codes, and if there's a load on the engine, it would be forced to "set" the idle higher. Not sure if it actually works that way, but now the idle is correct, and stayed good for a several mile drive. Maybe that means the issue is electronic? Now to see if the CEL comes back...
I wonder if by cleaning the EGR tube, it "confused" the computer since it was used to having it blocked? It's also likely that a piece of Carbon floated deeper into the engine when I was trying to clean out the area where the tube bolts on...maybe that had something to do with it? Kinda all speculation/shots in the dark...you all know more than I do. Still welcome any input, and I'll keep you updated!
Cleared the computer's codes again and started it with the AC on high and headlights on, to give it a load. My thought process is that maybe it sort of relearns something when you clear the codes, and if there's a load on the engine, it would be forced to "set" the idle higher. Not sure if it actually works that way, but now the idle is correct, and stayed good for a several mile drive. Maybe that means the issue is electronic? Now to see if the CEL comes back...
I wonder if by cleaning the EGR tube, it "confused" the computer since it was used to having it blocked? It's also likely that a piece of Carbon floated deeper into the engine when I was trying to clean out the area where the tube bolts on...maybe that had something to do with it? Kinda all speculation/shots in the dark...you all know more than I do. Still welcome any input, and I'll keep you updated!
06-15-2011, 07:50 AM
#3
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Join Date: Nov 2010
Location: Powder Springs, GA
Posts: 400
P0443 is the EVAP System Purge Control Valve in my 97 FSM. Would not worry at this point unless it comes back. You may have a vacuum line issue since you probably moved/disconnected some doing your EGR work.
06-15-2011, 12:44 PM
#5
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Join Date: Feb 2011
Posts: 142
Went about 30 miles today...still no CEL, and the idle is normal.
Have to admit, it scared me for a minute with how it was acting right after I cleaned that tube...ran REALLY bad for a few minutes, threw a knock sensor code, intake air temp sensor, and that P0443. It eventually started running okay, then I cleared the codes and drove it a while and it developed the weird idle issue. All seems to be acting okay so far now, though. Maybe I did get a chunk of carbon pushed into the engine and it was trying to burn it up?
Have to admit, it scared me for a minute with how it was acting right after I cleaned that tube...ran REALLY bad for a few minutes, threw a knock sensor code, intake air temp sensor, and that P0443. It eventually started running okay, then I cleared the codes and drove it a while and it developed the weird idle issue. All seems to be acting okay so far now, though. Maybe I did get a chunk of carbon pushed into the engine and it was trying to burn it up?
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