Measure missfire

[Luccatavares]

Okay!!!!
Seriously now! Haha
Searched every where and could find the answer.
So everytime I connect my obdII and clean codes something weirdo happens.
So after clean codes I start the car then what happen is, I get misfire codes from all plugs, TILL I drive around the block then is all gone!
Can somebody explain what's going on!!!!

LuccaT

[Okedokey]

What codes do you get? Just mis-fire, or something else?

[Luccatavares]

Just misfire

LuccaT

[jbain2]

What's your hardware setup? Any recent changes to the hardware? I would guess that the ECU has adapted and clearing the codes causes the ECU to read differently until it adapts again. Post VAG-COM codes.

[mtroxel]

When you clear the codes, your long term fuel trim is reset to 0. Then you need to drive a bit before the fuel trim figures itself out. But....that also means you probably have an intake air leak, so that the default long term trim is pretty far from correct. So like jbain, I wonder what codes you're clearing? Any of them have to do with fuel trim or intake air leaks? Those codes are there for a reason.....

[Luccatavares]

When you clear the codes, your long term fuel trim is reset to 0. Then you need to drive a bit before the fuel trim figures itself out. But....that also means you probably have an intake air leak, so that the default long term trim is pretty far from correct. So like jbain, I wonder what codes you're clearing? Any of them have to do with fuel trim or intake air leaks? Those codes are there for a reason.....

What's your hardware setup? Any recent changes to the hardware? I would guess that the ECU has adapted and clearing the codes causes the ECU to read differently until it adapts again. Post VAG-COM codes.

I have stock ecu. I never did anything to it.
I have some frames about a/c flap and a p2181 thermostat that's it.
I have a vcds but don't know how to use yet lol
This is my numbers on neutral gear


LuccaT

[Luccatavares]

LuccaT

[Rulty]

When you clear the codes, your long term fuel trim is reset to 0. Then you need to drive a bit before the fuel trim figures itself out. But....that also means you probably have an intake air leak, so that the default long term trim is pretty far from correct. So like jbain, I wonder what codes you're clearing? Any of them have to do with fuel trim or intake air leaks? Those codes are there for a reason.....

I was going to post this same exact thing, but it was taking too long on my phone. When you clear codes, even if there are no codes, it resets the fuel trims and everything. NOT only if there is a code.

[Luccatavares]

I was going to post this same exact thing, but it was taking too long on my phone. When you clear codes, even if there are no codes, it resets the fuel trims and everything. NOT only if there is a code.

That's a relief! Lol so doesn't mean I have a bad injector or dirty right?
I was wishing for a reply like your car is tuned, take to a shop to load files or something like that. Lol

LuccaT

[Rulty]

I wouldn't say its not a problem, you should be able to clear codes without having that happen. Think of it as more of a fine tuning that ECU does. As suggested prior check all your intake connections, id even clean maf depending on the miles you have, and check out your cam follower and fuel system just to be on the safe side. That's what I think should be looked at for peace of mind. If it were me I would let it go until I got a code.

[Luccatavares]

That what I was wonder, if maybe I had a tune in this car, I did clean the maf, ran the obd but no codes. I actually been using a lot gas, no matter the grade I can't go more than 230 miles per tank. I will get a fuel filter and also see foam and wait for codes

LuccaT

[mtroxel]

That what I was wonder, if maybe I had a tune in this car,

I have a Stage 1 tune in mine, it does not run rough after I clear codes. Something's not quite right there.

Here's a good explanation of what we're talking about. Group 32 in your VCDS.

http://wiki.ross-tech.com/wiki/index.php/Fuel_Trim_Info

[jbain2]

If you have a vacuum or boost leak somewhere the ECU can adjust fueling to account for that. If you reset the ECU then it may take some time for the ECU to recalibrate after driving.

APR has a good link on how to do logs that will show a number of things that might be helpful in this situation using VCDS.

https://www.goapr.com/support/datalogging.php


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[Luccatavares]

Nice I will really look into It! Thank you all

LuccaT