Here we go HT yet another idleing problem. I searched and got 62 results and nothing like this. Anyway, my car idles fine when it's cold and after it heats up. I can drive all day and no problems. The problem occurs when I turn on my headlights. I come to a stop and the car goes from like 800 to like 1400 and up and down. Does not get low enough to stall but when I turn off the lights it goes to normal. I've narrowed it down to being MAYBE my alternator or my battery. If you have had the same problem let me know. Thanks.

 

Alternator and battery are the most likely culprit. Drive to autozone and get them checked ...

For Free!

 

Anyone else?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eran &raquo;</TD></TR><TR><TD CLASS="quote">Alternator and battery are the most likely culprit. Drive to autozone and get them checked ...

For Free!</TD></TR></TABLE>x2

 

So I went to Autozone and had them check the battery and the alternater and they were both fine. I thought maybe it was my idle contril valve or maybe a vacuum problem but it only idles different when the lights are on. Someone help me figure this out.

 

switching on the lights makes the ECU (through the ELD in the fuse box) raise the idle a little to compensate for the alternator load on the engine.
A bad or dirty IACV will cause problems but usually it will bog the car not run it at 1400.

what is your setup? car/engine/ECU/intake mani/etc.

 

So this afternoon it started to rain so I put up the windows and turned on the AC. So this is only happening when there is a extra load on the engine. I can really get on the gas and push the motor but when I stop everything is fine until lights are on or the AC or something like that.

what is your setup? car/engine/ECU/intake mani/etc.[/QUOTE]

I drive a 92 hatch with a bone stock b16. The only thing it has is a short ram and I'm running a p28 ecu.

 

honestly get a Grounding kit .. dont buy a freaking 150$ kit or some BS its just 4gauge wire go down to your performance shop or your mechanic or w.e somebody that knows their **** and tell them to ground your engine properly and it will definitely help.. when i turn my headlights on my idle moves a little bit also but after i got my engine properly grounded it is fine and the car starts better also..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by robble36 &raquo;</TD></TR><TR><TD CLASS="quote">honestly get a Grounding kit .. dont buy a freaking 150$ kit or some BS its just 4gauge wire go down to your performance shop or your mechanic or w.e somebody that knows their **** and tell them to ground your engine properly and it will definitely help.. when i turn my headlights on my idle moves a little bit also but after i got my engine properly grounded it is fine and the car starts better also..</TD></TR></TABLE>

HMMM. I never thoght of that. I'll try it and see what ahppens.

 

x4

 

Try this:
Start the car, unhook the battery cable, If car dies, its the alternator.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99FBPSi &raquo;</TD></TR><TR><TD CLASS="quote">Try this:
Start the car, unhook the battery cable, If car dies, its the alternator.</TD></TR></TABLE>

That sounds hella dangerous.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chef Andre &raquo;</TD></TR><TR><TD CLASS="quote">

That sounds hella dangerous. </TD></TR></TABLE>

Why? You're just pulling the negative terminal.

 

when was the last time you did a tune up on the car. plugs, wires, cap, and rotor

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chef Andre &raquo;</TD></TR><TR><TD CLASS="quote">

That sounds hella dangerous. </TD></TR></TABLE>


actually its not, mechanics have been doing that for years!
its the easiest way to check to see if your alternator is working!
but i doubt thats the probem cuz it would have the opposit effect!
to me it sounds like you might have an electrical load detector problem!
this thing tells the ecu when theres a highor low electrical load therefore raising or lowering the idle depending on the load. its in the underhood fuse box.

hope this helps

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by oddball49 &raquo;</TD></TR><TR><TD CLASS="quote">
when was the last time you did a tune up on the car. plugs, wires, cap, and rotor</TD></TR></TABLE>

Whe I dropped the motor in last month.


<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by H-adict &raquo;</TD></TR><TR><TD CLASS="quote">


actually its not, mechanics have been doing that for years!
its the easiest way to check to see if your alternator is working!
but i doubt thats the probem cuz it would have the opposit effect!
to me it sounds like you might have an electrical load detector problem!
this thing tells the ecu when theres a highor low electrical load therefore raising or lowering the idle depending on the load. its in the underhood fuse box.

hope this helps

</TD></TR></TABLE>


Which fuse is this exactly or what am I looking for?

 

Fix/upgrade your grounds (I got a grounding kit off ebay for 15 bucks shipped), run a fused line directly from the positive terminal of the battery to the positive terminal of the alt. The larger the wire size (I'd say either 8ga or 4ga) the less resistance in the flow of electricity, these steps are also reffered to as the "BIG 3".