Strange Behavior

NewNeptune · Post by **NewNeptune** » Thu Sep 28, 2006 2:21 am

Anyone else have something like this happen? Any idea what it might be? I notice no lights on (like a CEL).Had some strange behavior from my Vibe this morning. I'm driving to work, about 20 miles of highway with a half-dozen stop lights. No problems. I pull into my company's parking lot and slow down for the first speed bump. As I am doing this, right about 5-8 MPH I feel it lurch, the RPMs come up a few hundred and hear a "Rrrrrr...." from the engine. Unusual, since it's downshifts are usually only felt as light bumps as I come to a stop. So, I go over a few more speed bumps and it keeps doing this. As I continue through the parking lot, I notice that as I finish going over the speed bump, I don't have to press the gas. I starts pulling away by itself. So I let it go and it gets up to about 6-7 MPH, the point right before it usually shifts into 2nd gear if you press very lightly on the gas. RPMs are about 1400-1600. Keep in mind, I'm not touching any pedals. It keeps doing this, so I put it into neutral and it still holds the RPMs up there. I rev it a few times, hoping maybe, like a game controller, it was just reading the throttle angle wrong. No luck. So (still rolling at ~5 MPH) I shut it off, wait a few seconds and start it up. No problem starting, but it's still revving at 1400-1600 RPMs. So I keep driving around, get it into a parking spot and put it in park. Finally, the RPMs slowly come down to the usual 800-900. Not satisfied that it was over, I back out of the spot, turn off the A/C and drive a little bit more. Now, it was no longer accelerating itself, but with the A/C off, each time I came to a stop it shudders like it's going to stall. After a second of shuddering, it returns to normal. So I pull back into the parking space and turn on the A/C. I hear it come on, but the RPMs don't come up from the 700 it was idling at, and it begins shaking. In order to get it to idle normally again, I had to restart it. Thanks for reading!

ToolGuy · Post by **ToolGuy** » Thu Sep 28, 2006 3:59 am

Never heard of this... Just a guess but it could be your Idle Air Control motor. It resides on the throttle body and they get dirty thus need a cleaning. If it does act up or go bad, no codes are usually thrown. They can even cause the car to stall at idle. It is just a guess but it would not hurt to clean it and try. Possibly it is an issue with the engine control module...

NewNeptune · Post by **NewNeptune** » Thu Sep 28, 2006 4:39 am

How do I clean it?The ECM wouldn't surprise me, since every morning now it is sluggish on starting. I hold the key and it cranks and cranks, catches, stumbles for a second and then finally starts.

Katscan · Post by **Katscan** » Thu Sep 28, 2006 4:53 am

I had this happen to my old Ford Escort ZX2. Does your car seem to pull harder when you turn on your AC(as if it were pulling more weight) and when you come to a stop you feel like your car is about to stall?I remeber it cost me well over $300 to get that fixed, apparently for me it was some regulator that went bad. The regulator(cant remeber the name) tells the engine to increase power when your AC is on to compensate for the power that the AC pulls from your engine.

northvibe · Post by **northvibe** » Thu Sep 28, 2006 4:59 am

you have a 06 right? so you should have a warranty then? but I think katscan is talking about a fuel pressure regulator? I had that go on my taurus and it had similar issues but mainly starting problems. Could be a dbw thing too if its eletronics are goofy i guess.

Baltovibe · Post by **Baltovibe** » Thu Sep 28, 2006 5:03 am

Possibly a bad TPS (Throttle Position Sensor)?Definition: A little gadget on the carburetor throttle linkage or fuel injection throttle body that keeps the engine control computer informed about the throttle opening (See Computerized Engine Controls). The TPS is a variable resistor that changes resistance as the throttle opens wider. The computer needs this information to change the air/fuel mixture. Adjustment is very critical and is best left to a qualified professional.

NewNeptune · Post by **NewNeptune** » Thu Sep 28, 2006 5:44 am

I have an 06 with the electronic throttle system. Yes, it's under warranty. However, if it's something I could clean, such as MiVibe-ToolGuy suggested, I would rather do that before having the dealer look at it. Especially since it has only happened once.

Katscan · Post by **Katscan** » Thu Sep 28, 2006 6:58 am

Ohh no, if its under warrenty have them do it. Cause if you try something and it doesnt work and they catch wind of it they might not fix it under warrenty.If its not one thing I learned from my last car, while its under warrenty. Bring it in for every little bump, rattle, strange noise. Get the kinks fixed before the warrenty expires. It could be something small now but it could lead to bigger(and costly) problems latter down the road.

NewNeptune · Post by **NewNeptune** » Thu Sep 28, 2006 7:05 am

I've learned you have to walk a fine line with the dealer. With my last two Malibus, both of which were lemons, the dealer got irritated with the number of stuff I brought it in for (most of which was fairly major). Since this is a different dealer and the first car I've bought with them, I don't want to (removed) them off. So, I'll wait and see if it recurs and possibly nail down some circumstances, so they aren't shooting in the dark. If it never recurs, then I'll be happy.

northvibe · Post by **northvibe** » Thu Sep 28, 2006 7:19 am

i say f em, i brought my vibe in 3 times right before the warranty was up just saying that it shifted hard and rattled. JUST so they would look it over and if something was broke, fix it. who cares if they get mad thats what they are their for. try cleaning the parts or unplug the battery for like 5 min then reconnect (negative) , but if its more intense than that id bring her in.

NewNeptune · Post by **NewNeptune** » Thu Sep 28, 2006 7:27 am

Did they fix the hard shifting? Mine does that randomly. I have nailed down though that if I'm in stop and go traffic and traffic doesn't quite stop, it will kick into gear really hard. That one I intend to bring in.

ToolGuy · Post by **ToolGuy** » Thu Sep 28, 2006 8:49 pm

Here is a pic of the Idle Air Control #3. I have not taken mine off to clean but I have cleaned the throttle body out and sprayed plenty of cleaner on all parts. Normally, once you take the part off on other cars I have done, you just clean the hole it came from and the part itself.

Attached files

ToolGuy · Post by **ToolGuy** » Thu Sep 28, 2006 8:53 pm

Here is a pic of the throttle position sensor #2. Never had one of these go bad on my cars but a friend did and it threw a code. If worst comes to worst, try cleaning the throttle body out by hand. The spray cleaner is not expensive. Just remoeve the intake hose, spray the cleaner in all around and wipe it out with a rag. Work the "flap" back forth, spray more down with throttle flap open, use your hand of course to hold it open. Otherwise I am stumped on this one...

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Strange Behavior

Strange Behavior

Re: Strange Behavior (NewNeptune)

Re: Strange Behavior (MiVibe-ToolGuy)

Re: Strange Behavior (NewNeptune)

Re: Strange Behavior (NewNeptune)

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Re: (northvibe)

Re: Strange Behavior (NewNeptune)

Re: Strange Behavior (MiVibe-ToolGuy)