I can not do smog check for my 1997 ti because there's no communication between my car computer and the smog test computer.
Does anybody ever have the same problem?

I wish this had been answered
 

I just came back from the same experience. I was told that the wires looked fiddled with but I will be taking it back to see if they can fix it. But apparently there is no communication between my car and their machine.

A software upgrade may be needed at the inspection station. Basic OBD2 Software does not aways work on Bimmmers and the Computer system has a lot to do with it as well. Some of the early E39 5 series had read problems, but I have never heard of a 318ti with such. sounds like their machines are the problem.

cossieturbo

I'm having the same problem right now is there anyone that can knows about it. I passed everything except FAILED ODB TEST, so I failed. I think the point of the smog test is to check for emission, passed it with flying colors failed the ODB.

Where are you located in Cali? I might be able to help you out. I'll probably need to look at your car though.

Same Problem - What's the fix?
 

Hey, I know this thread is like 3 years old, but I was wondering if you could help me out. I took my 96' ti in to get smogged and the tech said my car computer is not talking to his machine. He asked if I had had any work done recently (which I've had a lot), but I've also driven over 400 miles since the last work was completed. He said I might need a new computer!? :eek: This seems wrong to me.
So I was wondering what you ended up doing to pass smog. I've read in some other threads about guys going to a smog referee to get tested. Would that be an option to get around this problem?
Any help would be much appreciated.
Ryan

check your fuses, you might have the one that provides power to the OBDII diagnostic port blown, use a voltmeter because sometimes they can look good but still be burned, if you don't have a voltmeter you can always get a mechanic to do it, but I'd stay away from the one who recommended the new computer

My car failed the smog test 2 weeks ago due to a crack on the intake boot. The hole is after the MAF so the unmetered air was being sucked in causing the engine to run lean.

I replaced the leaky boot and took back to the same smog shop thinking that my car will definitely pass this time. However, he could not establish connection from his smog machine to my OBD II slot.

I had unplugged my battery a week ago to replace the oil filter housing gasket. I also checked my fuses and they seem fine. What can cause this to happen?

Remove the cap on the diagnostic connector. The cap itself should have connector pins. The cap establishes a connection to the OBD connector.

I found the cause of my failed connection.

I had reset the oil indicator the previous night, and forgot to twist tight the 20 pin connector lid under the hood. After tightening the cap, I was able to establish connection from the OBD plug under the steering wheel.

So I also failed the OBD test but, passed the emissions part :( SMOG TESTS stress me out!!! The smog guy said that it was because my computer was "not ready". He told me to drive around for a week and then come back and get re-tested. I had my oil changed the same day as the smog test so they reset my lights. Does anyone know if this is why I night have failed the OBD part? I also had my mass airflow and battery replaced a few months ago but, that shouldn't matter at this point. Anyone have any ideas?

Bump anyone?

Reseting the OBD after oil change
 

The smog tech is right. Once you reset your OBD, then you need at leat 150 miles to accumulate new data to satisfy the smog tester computer. This is to prevent people from just resetting their bad cells and pass the test.

After passing my test last March, my cat cell came up 2 weeks after passing the smog (barely). Now I know that the reason I failed the smog was more than a cracked intake boot. It was my cheapo catalytic converter I had replaced 3 years ago. I used after market cat ($350) and the shop said that they don't warranty it for more than 1 year. I guess that'y why BMW charges $1000 for the original cat, because they're much better and will last 10 years.