Failed Smog Test due to odd OBDII issue. Any Ideas.

genscripter

Veteran Member
Joined
Feb 18, 2008
Location
Los Angeles
TDI
98 Jetta
I've been driving my '98 Jetta TDI for years without issues. A few months ago, I had to replace some electrical things, but aside from that, it's been driving fine.

I got the dreaded DMV letter stating that I needed to get a smog check. I went to my usual place, but there was a new guy. I don't think he knew much about diesels.

He ran the check, and everything passed. However, he said my "EGR and/or VVT System" are "not ready." He said to drive it for 50-100 miles and come back.

That's confounding, because I hadn't recently cleared the codes or anything. I had been driving it around for weeks, so everything should be "ready."

I looked up this thread on the tdiforum that had a similar issue, and the man put in the original chip and it passed the test. I never put in a new chip. Everything is stock.

I ran my VAG-COM to see if there was an engine code. There wasn't, but there was a "generator" fault:

01117 - Generator Terminal DF Load Signal
27-00 - Implausible Signal


This might have been an old fault from when I replaced the alternator a few months ago, because now that I think about it, I never cleared the code after replacing the part. I just drove it until the check engine light disappeared. I have a digital voltage gauge, and my voltages have been normal (around 13.5V). On occasion, I run a cig-lighter minifridge that can draw down the current to 12.9V, so maybe that tripped the "Implausible Signal."

Do you think the Generator fault is causing the "not readiness" of the EGR OBDII values?

Or did the newbie smog tech screw up my test? He seemed completely uninformed about how to do the test.


I'm going to delete the fault and see if it returns tomorrow after a long drive. That will help me figure out if that alternator or connections are off.
 
Last edited:

genscripter

Veteran Member
Joined
Feb 18, 2008
Location
Los Angeles
TDI
98 Jetta
Vagcom should tell you if your Readiness is "Ready" or "Not".

Clear your codes, drive your car, check your readiness, and go back to Jiffy Smog.


The only code that had a readiness issue was that generator fault.


At the end, it said:

Readiness: N/A

I'll clear it and take it back Monday.
 

Matt-98AHU

Loose Nut Behind the Wheel Vendor
Joined
Apr 23, 2006
Location
Vallejo, CA
TDI
2014 Passat SE DSG, 2005 Passat wagon, 2004 Touareg V10.
The generator load signal code won't show up on a generic OBD2 scanner with regards to emissions.

The reason you failed was due to a readiness monitor not being set, NOT for a code stored.

Some tunes with EGR deletes don't set the readiness monitor for the EGR... Other issues may just be that the MAF readings for one reason or another aren't corresponding correctly when the EGR is commanded on, not a big enough discrepancy to set a code, but enough to make it difficult for the readiness to set.
 

genscripter

Veteran Member
Joined
Feb 18, 2008
Location
Los Angeles
TDI
98 Jetta
The generator load signal code won't show up on a generic OBD2 scanner with regards to emissions.
The reason you failed was due to a readiness monitor not being set, NOT for a code stored.
Some tunes with EGR deletes don't set the readiness monitor for the EGR... Other issues may just be that the MAF readings for one reason or another aren't corresponding correctly when the EGR is commanded on, not a big enough discrepancy to set a code, but enough to make it difficult for the readiness to set.

My TDI is bone stock. It's passed smog checks since they started doing them in California for diesels. Any ideas on how to get that discrepancy to set the readiness?
 

genscripter

Veteran Member
Joined
Feb 18, 2008
Location
Los Angeles
TDI
98 Jetta
UPDATE:

I cleared the generator code last week and drove the jetta around for the weekend. Probably put on a hundred miles.

This morning, I happened to be near my smog shop and figured I would pop in to get the codes checked. He plugged in the device and it said I passed.

Not really sure if clearing the code had anything to do with the readiness or whatever, but whatever I did, it worked.
 

Steve Addy

Top Post Dawg
Joined
Aug 7, 2002
Location
Iowa
TDI
97 Mk3
UPDATE:

I cleared the generator code last week and drove the jetta around for the weekend. Probably put on a hundred miles.

This morning, I happened to be near my smog shop and figured I would pop in to get the codes checked. He plugged in the device and it said I passed.

Not really sure if clearing the code had anything to do with the readiness or whatever, but whatever I did, it worked.
Congrats on passing, I know this is often a headache for people in states with emissions tests, especially when you consider that it's hard to replace the mpg of our cars should the condition persist and you be unable to pass ever.

Steve
 

genscripter

Veteran Member
Joined
Feb 18, 2008
Location
Los Angeles
TDI
98 Jetta
congrats on passing, i know this is often a headache for people in states with emissions tests, especially when you consider that it's hard to replace the mpg of our cars should the condition persist and you be unable to pass ever.
Steve

"mpg?"
 

genscripter

Veteran Member
Joined
Feb 18, 2008
Location
Los Angeles
TDI
98 Jetta
Ah. I figured you meant miles per gallon, but when I originally read it, I thought maybe you meant replacing a part, like the ECU.
 
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