Questions and Answers

VW Golf DTC 1582 Q. Hi there, I have a 1998 Golf with the 4 cylinder. 2.0 engine (ABA). I've driven this car 105,000 miles and it's still an EXCELLENT car. I do all of the maintenance work myself (oil, exhaust, plugs, liquids etc). I'm a proud owner and lightweight hobby mechanic.

I don't get much help from VW though, (probably not a surprise).

In any case, my car has been idling a little rough from time to time, and my engine light (MIL) when on a while back. I used an OBDII scanner to retrieve the engine code and the code it retrieved was "P1582" which is; "Idle Adaptation at Max" (description from Bently repair manual).

Well, I looked it up in my trusty Bently repair manual and found, after reading a little, that the problem *might* be related to the Idle Air Control Valve (IAC). The manual shows a picture of where the valve is located, however, the picture seems to be a differ engine year, as the part is not located there on my 1998 engine!!!

So, finally, (drum roll), here are my questions:

1. Can you tell me what exactly what causes this P1582 code? And what should do to try to fix it?
2. Can you tell me where the Idle Air control valve is on a 1998 2.0 liter 4 cylinder engine?

Thanks much,
Andrew

A. There are a few things that can cause this code. Gasoline in the oil can do it. This can be fixed by an oil and filter change. It can be caused by worn out fuel injectors staying open too long and not allowing the idle adaption.

Significant blow by will also cause this code to set. If there is a lot of blow by you should do a compression test to make sure the piston rings are still good. Compression should be between 130 to 190 psi. If there is a 40 psi difference between cylinders, the engine is worn and needs overhauling.

It can also be caused by a bad Throttle Valve Control Module.

At this point, I would suggest giving the IACV and throttle chamber a good cleaning and see if that helps. If not then there will be some testing that has to be done to determine if it is one thing causing the code, or a combination of things throwing the code.

Added 5/21/03:

It has been my experience that this code pops up whenever oil condenses on the Mass Air Flow (MAF) sensor. I remove the MAF assembly, spray a degreaser on it like WD40 or carburetor cleaner sprays, and put it back together. his happens when you shut off the engine and fumes from the crankcase work their way back through the air intake system. There is a fix for this from VW but it requires a little skill to install and some wiring. I think it is easier to clean the MAF sensor once a year.

Regards,
Tom
Willoughby Hills, Ohio

My note: Tuner cleaner works very well aslo and doesn't leave a residue.