Multiple cylinder misfire

Hey davidrabor74,

What was is it that the electrician tested?
Which cylinders had the issue that he found?

Have you have the fault codes checked?

If not the place to start would be to check for fault codes and let us know what you have.

This will tell you which cylinders are misfiring.

Guide below:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Regards, Joe

Hey davidrabor74,

Perfect, thank you.

What was it that the electrician had tested and what did he find?

Regards, Joe

Hey DAVIDRABOR74,

From the data I have cylinders 2, 4 and 6 are the front 3 cylinders, bank 2.

You have codes for -

Random misfire and misfires on all of bank 2 (P0300, P0302, P0304, P0306)

Also -

P0172 - bank 1 being too rich
P0174 - bank 2 too lean
P1150 - Air/Fuel Ratio Sensor Circuit Range/Performance Bank 2 Sensor 1
P1346 - Variable Valve Timing Sensor Bank 1 Range/Performance Problem

Regards, Joe

Hey davidrabor74,

With the misfire issue being on bank 2 only and also not having an issue during the closed loop phase warm up chase you need to look into the oxygen sensor fault and the camshaft sensor sensor fault.

I would advise you will need access to a scanner with live data to monitor signals received by the ECM.

A compression test or a relative compression test would be useful to see if you have any variation between cylinders and between banks. This would point potentially to a timing issue.

A check for vacuum leaks, to make sure you don't have an intake leak on bank 2.
Guide below:
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Was all the work done after you started having this issue, nothing has improved?
Was the variable valve timing sensor code present before the timing belt was changed?

Have they already checked the Air fuel ratio sensor for bank 2?
If not this would be an easy thing to replace as it is on the front bank and at the top of the exhaust manifold. It is also relevant for bank 2 misfires and is ignored during the warm up phase. You would need to monitor what the ECM is seeing from this sensor to diagnose an issue.

Hope this helps, let us know if you have further questions.

Could you also please give us the readings from the long term fuel trims?

Regards, Joe

Hey davidrabor74

If you did not have the VVT code before they changed the timing belt then it is very likely the timing is not correct. The shop will need to recheck this.

After this is done confirm you no longer have the VVT code and what you are left with.

What was the order of events here?

Did you have the misfire originally?
What codes did you have to start with?

Run me through the story including which codes you had at each stage.

Regards, Joe

Hello, If I could jump in here a quick second. Did you say that the Long Term Fuel Trim on bank #2 was -40.62? I would almost suspect a faulty PCM/ECU at this point. That reading is off the chart and if the tech you had looking at the injectors said that when it went to closed loop that there was no voltage present at the injectors for bank #2 would indicate an internal PCM/ECU fault. If you have access to Noid lights, this would be an easy way to confirm if the fuel injectors were getting voltage or not at closed loop operation. You should be able to rent these from a parts store, like AutoZone, free of charge. Do a Noid Light test by plugging the Noid Light into the fuel injector connector and start your vehicle. Get back to us with what you find out please.

Thanks,
Alex
2CarPros