Weird Smog Check Failure - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

gepeyo · 08-15-2023, 05:07 PM

Hey Everyone, its been a while since I've posted in the forum.

I gotten notice that I had to take my car into a shop to have it Smog checked as a Star station, so I took in my car today to have it checked. My car was running perfectly fine and there was no check engine lights or anything prior to driving my car into the shop.

When I arrived at the shop, the guy took my car in and after 10 minutes he told me that my car's OBDII reader was not getting communication with their system whatsoever. After 3 tries though, he was able to get it to connect into their database but the Smog apparently failed due to an OBDII error with low communication. (Code U0155). After they returned my car to me, my car suddenly had a check engine light and it went into limp mode, which made me panic at first but I assume the smog checker caused this when it accessed my OBDII. Looking at the paper he gave me on return everything else passed besides the OBDII.

I was wondering if anyone experienced this when they had their car smogged?

The extra details:
Car had a UEL tuned with a open flash tablet in the past, but since then has been removed/untuned. It also passed smog 2 years ago after having the UEL and OFT taken off.

About 4 years back, my car has a CEL due to a solenoid valve breaking, its since then been fixed by a shop and hasnt been a problem since.

Clipdat · 08-15-2023, 05:31 PM

What's the new code it's throwing? Were you able to pull it?

finch1750 · 08-16-2023, 04:06 AM

Quote:

Originally Posted by gepeyo

Hey Everyone, its been a while since I've posted in the forum.

I gotten notice that I had to take my car into a shop to have it Smog checked as a Star station, so I took in my car today to have it checked. My car was running perfectly fine and there was no check engine lights or anything prior to driving my car into the shop.

When I arrived at the shop, the guy took my car in and after 10 minutes he told me that my car's OBDII reader was not getting communication with their system whatsoever. After 3 tries though, he was able to get it to connect into their database but the Smog apparently failed due to an OBDII error with low communication. (Code U0155). After they returned my car to me, my car suddenly had a check engine light and it went into limp mode, which made me panic at first but I assume the smog checker caused this when it accessed my OBDII. Looking at the paper he gave me on return everything else passed besides the OBDII.

I was wondering if anyone experienced this when they had their car smogged?

The extra details:
Car had a UEL tuned with a open flash tablet in the past, but since then has been removed/untuned. It also passed smog 2 years ago after having the UEL and OFT taken off.

About 4 years back, my car has a CEL due to a solenoid valve breaking, its since then been fixed by a shop and hasnt been a problem since.

Same thing happened to me. Should be a simple fix with the right smog guy. Ill post my ordeal/fix in the morning for you

finch1750 · 08-16-2023, 02:00 PM

@gepeyo So I had the same thing happen with my car not reading on the machine, but when the tech went to try and push the connection better my dash through every light it could. Turning the car off and on cleared everything except the CEL. While not in limp mode, it did drive like total shit for a while while relearning.

I took the car to Neal's new shop and luckily he was there and helped get me squared away pretty easily.
The OBD on the early years get bad connections and don't read. He loaned me an obd extension and sent me to his smog guy around the corner and it passed no problem.

So try an extension and find a smog shop that will allow it. If that doesn't work the OBD port itself may need to be replaced.

strat61caster · 08-16-2023, 07:34 PM

+1 real fix is fixing/swapping the obd2 port so the pins engage properly. If you’re really skilled you can repin the original connector, I’m a monkey so I immediately broke it. Easiest I found is splicing in a pigtail I got from iwireusa.

Ultramaroon · 08-16-2023, 09:15 PM

That's it. OP, you know how a wall socket wears out so we bend the prongs on the vacuum cleaner plug to make it work? Same thing, only now the plug has sixteen prongs/pins.

villainous_frx · 08-17-2023, 12:51 AM

Quote:

Originally Posted by Ultramaroon

That's it. OP, you know how a wall socket wears out so we bend the prongs on the vacuum cleaner plug to make it work? Same thing, only now the plug has sixteen prongs/pins.

This is an excellent analogy.

jflogerzi · 08-17-2023, 06:54 PM

I have seen this when the port disconnects during my track days. I just used zip ties to make my reader very secure and its mostly not an issues now.

finch1750 · 09-12-2023, 12:54 PM

@gepeyo did you ever get this squared away?

08-15-2023, 05:07 PM	#1
gepeyo Opal86 Join Date: Nov 2013 Drives: 2013 10 Series #Opal86 Location: San Francisco Posts: 378 Thanks: 202 Thanked 140 Times in 111 Posts Mentioned: 26 Post(s) Tagged: 0 Thread(s)	Weird Smog Check Failure Hey Everyone, its been a while since I've posted in the forum. I gotten notice that I had to take my car into a shop to have it Smog checked as a Star station, so I took in my car today to have it checked. My car was running perfectly fine and there was no check engine lights or anything prior to driving my car into the shop. When I arrived at the shop, the guy took my car in and after 10 minutes he told me that my car's OBDII reader was not getting communication with their system whatsoever. After 3 tries though, he was able to get it to connect into their database but the Smog apparently failed due to an OBDII error with low communication. (Code U0155). After they returned my car to me, my car suddenly had a check engine light and it went into limp mode, which made me panic at first but I assume the smog checker caused this when it accessed my OBDII. Looking at the paper he gave me on return everything else passed besides the OBDII. I was wondering if anyone experienced this when they had their car smogged? The extra details: Car had a UEL tuned with a open flash tablet in the past, but since then has been removed/untuned. It also passed smog 2 years ago after having the UEL and OFT taken off. About 4 years back, my car has a CEL due to a solenoid valve breaking, its since then been fixed by a shop and hasnt been a problem since.

08-16-2023, 02:00 PM	#4
finch1750 Undisputed El Presidente Join Date: Jun 2012 Drives: Zenki 37J ZN6 Location: Stockton, CA Posts: 11,593 Thanks: 9,403 Thanked 9,411 Times in 5,270 Posts Mentioned: 374 Post(s) Tagged: 33 Thread(s)	@gepeyo So I had the same thing happen with my car not reading on the machine, but when the tech went to try and push the connection better my dash through every light it could. Turning the car off and on cleared everything except the CEL. While not in limp mode, it did drive like total shit for a while while relearning. I took the car to Neal's new shop and luckily he was there and helped get me squared away pretty easily. The OBD on the early years get bad connections and don't read. He loaned me an obd extension and sent me to his smog guy around the corner and it passed no problem. So try an extension and find a smog shop that will allow it. If that doesn't work the OBD port itself may need to be replaced. __________________ "Just like how a strut bar somehow enables you to corner 20MPH faster around a cloverleaf on-ramp, when the reality is, you can do it already but you just don't have to balls to do it." - CSG David

08-16-2023, 09:15 PM	#6
Ultramaroon not playing cards Join Date: Sep 2014 Drives: a 13 e8h frs Location: vantucky, wa Posts: 32,395 Thanks: 53,053 Thanked 37,228 Times in 19,308 Posts Mentioned: 1117 Post(s) Tagged: 9 Thread(s)	That's it. OP, you know how a wall socket wears out so we bend the prongs on the vacuum cleaner plug to make it work? Same thing, only now the plug has sixteen prongs/pins. __________________ service manuals

09-12-2023, 12:54 PM	#9
finch1750 Undisputed El Presidente Join Date: Jun 2012 Drives: Zenki 37J ZN6 Location: Stockton, CA Posts: 11,593 Thanks: 9,403 Thanked 9,411 Times in 5,270 Posts Mentioned: 374 Post(s) Tagged: 33 Thread(s)	@gepeyo did you ever get this squared away? __________________ "Just like how a strut bar somehow enables you to corner 20MPH faster around a cloverleaf on-ramp, when the reality is, you can do it already but you just don't have to balls to do it." - CSG David

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