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Regallsx
06-26-2021, 12:33 AM
Hey everyone, noob here. Just got my lq4 swapped regal "running" and I'm having a billion misfires in all cylinders. I feel like it's running too rich due to the egr delete. Can someone hold my hand (figuratively speaking) and help me to do my first tune..im using pcm hammer and tuner pro. I'm not a complete moron when it comes to cars but would love not to brick my only pcm...thanks!!!

B52Bombardier1
06-26-2021, 12:56 AM
What PCM? P01 or P59? What operating system number?

Rick

Regallsx
06-26-2021, 01:26 AM
Pcm 0411, OS 12208322

B52Bombardier1
06-26-2021, 01:44 AM
Hello,

How about what is in this attachment?

Rick

Regallsx
06-26-2021, 01:52 AM
Is that all I need to remove egr? Do I need to tune VE and adjust spark advance??

B52Bombardier1
06-26-2021, 02:22 AM
Hello,

I can't explain your misfires- too little information provided. But killing off EGR in the manner described in that attachment will do it but leave you with a few DTC codes to also kill off:

P0401 Exhaust Gas Recirculation Flow

P0402 Exhaust Gas Recirculation Flow Insufficient Detected

P0404 Exhaust Gas Recirculation Flow Excessive Detection

P0405 Exhaust Gas Recirculation Control Circuit Range/Performance

P1404 Exhaust Gas Recirculation (EGR) Closed Position Performance

P1406 EGR Valve Pintle Position Circuit

P1409 EGR Vacuum System Leak

Some of these you might have, some maybe not.

I have not tuned my VE or spark advance. This is because I can monitor things like Knock Reduction, Long Term and Short Term Fuel Trims to see that my engine runs plenty good enough for me. I have zero Knock Reduction and plus / minus 5 percent LTFT and STFT across the entire RPM operating range of my engine. Good color on my spark plugs, good acceleration, good shifting, a perfect 650 RPM idle and good oxygen sensor response on both banks.

I have had to change the cam sensor, the ECT sensor, a few fuel injectors and a coil pack or two to achieve all of this. I also had to clean my MAF screen and perform a crank position sensor relearn.

What else have you changed on your engine? Different cam, heads or intake?

Rick

Regallsx
06-26-2021, 04:52 AM
Engine is stock as far as I know. I have good spark, 91 octane fuel in it right now with 317 heads (stock). I currently do not have 1st or 4th (no codes) perhaps due to my egr fault and evap fault (limp mode?) So far my LTFT is -1%.

B52Bombardier1
06-26-2021, 10:31 AM
It definitely sounds like limp mode on your transmission but I don't believe that has anything to do with an EGR or EVAP fault. Do you have a way to check electrical power with a multimeter to the fat transmission plug?

Does your speedometer show speed when your vehicle is moving? What do you have for an OBD2 data monitoring capability?

Rick

Regallsx
06-26-2021, 02:54 PM
Yes I can do pin checks at the plug, my speedo is currently not connected and I have a autel scanner as well as tech2 pro.

B52Bombardier1
06-26-2021, 04:26 PM
Drive your vehicle and see if the PCM sees a speed going down the road using your Tech2. If it does not have that signal from the Vehicle Speed Sensor in the tail of the transmission, it won't shift on its own and is likely in Limp Mode. Basically, no speed . . . why should the transmission shift???

Your Tech2 can also tell you what gear it thinks it is in.

I have had a bad PCM that caused me random misfires. Yes, it is rare but can happen.

Rick

Regallsx
06-26-2021, 05:29 PM
Ok I will try that and follow up. Thanks broski! FYI I am currently running open shorty headers...maybe AFR sensor reading lean causing rich condition???

B52Bombardier1
06-26-2021, 09:40 PM
Today, when I open my header / exhaust cutouts, I often get a temporary O2 sensor error. So with your open, shorty headers, I would expect similar behavior. Before I had my full exhaust and only had open headers, I had to go to the muffler shop and get two, three foot lengths of pipe to shield my O2 sensors and to make my engine run right. It had no mufflers and was loud but it ran properly.

You might consider the same.

Rick