Date: Tue, 9 Sep 2003 13:03:23 -0600
Reply-To: Steve Blackham <ssblackham@MAIL.BIGZOO.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Steve Blackham <ssblackham@MAIL.BIGZOO.NET>
Subject: Re: HC high at Idle - Any Ideas?
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Phil:
A leak in the exhaust system upstream from the O2 sensor will also
cause your symptoms. Check for leaks and bad gaskets. Put a rag
over the tail pipe and listen for leaks. The exhaust leaks cause the
O2 sensor to think its running lean from the air leaks. It
compensates by enriching the system. The volume at open throttle
keeps the air out so the O2 sensor operates normally
Steve
"Walker, Phil" <Phil.Walker@BROOKS.COM>Wrote:
<Subject: HC high at Idle - Any Ideas?
<Well it is inspection time again, only this time I am having emissions
<problems.
My 2.1 engine has about 30K on it and the rotor/cap/plugs were changed about
20K ago (3 years). I went in for the emissions and inspection and got the
following feedback...
RPM 2550
HC CO
STD 220 1.2%
Read 59 .61%
Pass Pass
RPM 895
HC CO
STD 220 1.2%
Read 505 .26%
Fail Pass
So I combed the archives and I found a post from Steve Blackham in 2001
(Steve happens to live about 5 miles from my house!). He was having the same
scenario and he documented (quite thoroughly I might add) how he addressed
the problem. Most of the fix stemmed from an adjustment of idle and timing.
I emailed Steve to get some more advice and he recommended I check the plugs
because he thought I might have a leaky injector. Tonight I checked the
plugs (all white - chocolaty). While I was getting to the plug under the air
filter I noticed the clamp on the engine side of the AFM was very loose from
the fuel line job I did a couple of weeks ago (YEA! - I got that done). I
basically never tightened it (good thing I've only driven to the inspection
since!). Could this also be contributing to the high HC at IDLE? Maybe the
O2 sensor is showing lean from the extra O2 so the computer is squirting
more juice?
Anyway, I'm going to correct that, but I want to do anything else to make
sure I pass for sure when I go back. I don't have a timing light, so I
hesitant to jump into the idle and advance. The idle is around 900 and
although I told Steve it might be a little rough, I'm really not sure. It
has never idled like my old Acura legend, but it doesn't hunt. It just
seems....well....you know a little weird, but after all it is a VW!
I took a look at the cap and rotor and they look descent, but there was
nothing suspicious.
Any other advice would be helpful. I'm going to do plugs, cap, rotor, and
air filter (it's dusty out here in Utah on those dirt roads!) just to be
sure.
Steve, thanks for the email. Your advice was helpful.
Phil
89 Westy
