Inconsistent master fuel value, running very rich.

[Jed_dc2]

So before my car went to the dyno I found myself having to adjust the master fuel value up and down to maintain a stable AFR between starts.

Sometimes would be lean sometimes would be rich.

Got tuned last year and nothing has been touched on the ECU since but now when I start my car it's running at 8 AFR for some reason.

I have already checked fuel pressure and for leaks, no trims are applying in the tune its just went stupid rich for no reason.

Please don't ask me to send logs because I'm not really keen on running the engine when it's that rich.

What should I be looking at to resolve this as its driving me insane It was completely fine the day it was tuned.

Thanks 

Jed

[Brad Burnett]

is the map sensor connected and working?

I had a map sensor fail and cause similar issues.

[Jed_dc2]

18 minutes ago, Brad Burnett said:

is the map sensor connected and working?

I had a map sensor fail and cause similar issues.

Yeah it's definitely connected and to the best of my knowledge its working.

We managed to tune the car with it so thinking it must be OK unless it's an intermittent fault ?

[Adamw]

5 hours ago, Jed_dc2 said:

Please don't ask me to send logs because I'm not really keen on running the engine when it's that rich.

You will need to do a log, there is no way anyone can help without it.  Running rich for a short period of time under no load is not going to do any harm.

Likely related to the issue in your other post with the 5V error as the knock sensor circuit has nothing to do with the 5V output at all so there is still an issue there somewhere.  The only way disconnecting the knock sensor could change the 5V output was if there is a short in the loom.  

[Jed_dc2]

9 hours ago, Adamw said:

You will need to do a log, there is no way anyone can help without it.  Running rich for a short period of time under no load is not going to do any harm.

Likely related to the issue in your other post with the 5V error as the knock sensor circuit has nothing to do with the 5V output at all so there is still an issue there somewhere.  The only way disconnecting the knock sensor could change the 5V output was if there is a short in the loom.  

Yesterday I unbolted knock sensor from block then all sensors were reading correctly on the laptop but it was still extremely rich.

I'm going to look at sensor wiring after work, my oil pressure sensor uses a 5v output so will start there.

[Jed_dc2]

Here is a copy of my tune a a short log at idle showing rich afr.

I noticed the actual pulse width was 6ms which seems big to me ?

I will keep looking at wiring but cant see anything obvious so far.

 

[essb00]

Your MAP sensor is not working on that log - it is reading almost as BAP.
Check the vacuum hose from intake manifold going to the MAP sensor.

[Jed_dc2]

1 hour ago, essb00 said:

Your MAP sensor is not working on that log - it is reading almost as BAP.
Check the vacuum hose from intake manifold going to the MAP sensor.

Looking at the log again I can see it's just reading 14.5 constantly.

Looking for new sensor now.

[Adamw]

Both the oil press and MAP sensor inputs show zero volts.  This means those inputs are in fault state and using the error value (100kpa for MAP).  Did the oil pressure used to work?  I would start by confirming you have 5V and ground at those sensors before replacing them.  It would be unlikely for two sensors to fail at the same time.