duranvw

iTrader: (2)

Hey guys,


I've been battling this issue for months now. The car is getting rich at idle and cruise. The AFRs will bounce around all over the place, sometimes 13.X then drop to sub 10:1 while cruising and idle. When I first start the car it hits 14.7 - 15.0 for a few seconds then gets rich.


It posts this code almost immediately:
P0069 Abnormal Correlation Between MAP sensor and BARO Sensor (main)


I have tried swapping the following:
-Different MAF
-Two different MAP sensors
-Boost Leak tests
-Different ECU
-IACV
-TPS


I am wondering now if there is possibly a wiring/voltage issue going to either the MAF or MAP? Attached is a data log from me cold starting the car and the AFR jumping around (this not even as bad as it has been). The AirVol log, which I don't normally log is jumping all over the place, anyone have any ideas on this data log?

Biggiesacks

can you post more info about the car? Mods etc. Looking at your log your fuel trims are not looking good. 12.5 LTFT low and 6.8 mid is way off from optimal. Make sure you include what kind of injectors/fuel pump setup you are using in your mods list and also what scaling and latency values you have for them in your rom.

duranvw

iTrader: (2)

I had a fairly bad boost leak at the injector seals that I found during troubleshooting. I replaced my stock injectors with PTE780's and am currently using the following scaling and latencies. However I will say the problem is identical to before and after swapping the injectors. I agree there are some adjustments to be made on the trim.

Injector scaling: 665
Latency:
4.69v 3.312
7.03v 2.184
9.38v 1.368
11.72v .888
14.06v .600
16.41v .408
18.68v .288

The rest of the mods include :

AMS intercooler
Injen intake, lower and upper IC piping
Tial BOV (I tried putting stock BOV back on, same issue)
Walbro 255
GrimmSpeed 3port BCS
Omni 3BAR MAP (also tried stock MAP and tune, and a JDM 3 BAR with tune change)

I've put the car nearly back to stock from all these parts and continued to have the same problem

Biggiesacks

Once you have all the boost leaks figured out the 2 things i would move to next are rescaling the MAF for your intake, and dialing in the fuel injectors, you want the trims to be <3% +- and within 5% of eachother. Also might be worth checking for exhaust leaks around the 02 housing, its probably not this but worth ruling out.

duranvw

iTrader: (2)

Thanks for the reply.


I almost forgot I installed new exhaust manifold, downpipe and o2 sensor while the problem was occurring and it did not change anything, I don't think I have any exhaust leaks.


Where do I start on MAF scaling? It's something I've never touched in the tune


Does that AirVol log seem normal? Is that a valid item to log?

Biggiesacks

Here is some reading material on MAF scaling. Im still running the stock intake so i don't have first hand experience with it.

https://www.evolutionm.net/forums/ec...-maf-pics.html

I don't have AirVol as part of my normal logging but it might be useful for troubleshooting. For most tuning logging 1byte load (Tephra) or 2 byte load (stock roms) pretty much gets you what you need in that department.

duranvw

iTrader: (2)

Yeah I don't normally log that either I figured I would just log everything I could to possibly see some red flags. I typically do the 2byte load log, which the values don't fluctuate to much during the idle.

I will have a look at that post, I could put my stock intake back on which I haven't tried before, however the car was running well for a while on all these mods. It wasn't like a part was changed and the problem occured

Biggiesacks

Well just having your logs to go off of the glaring red flag are those trims. They are just a symptom though. It could be a symptom of an issue with the tune or there could be some mechanical issue causing it. The ECU is adding alot of fuel to try and hit stoich in closed loop, again that could be because of issues with the tune or it could be something like a clogged injector or failing fuel pump/regulator. Hard to say from where I'm sitting.

duranvw

iTrader: (2)

My gut says its something mechanical, like I said this issue was persistent before I changed injectors, and I even put stock MAP sensor and stock tune on the car with the same issue.






I have an AEM FPR with a gauge that I can put on and just verify I'm holding proper fuel pressure.




That and test with stock intake as well to see if there's a difference.