MILEAGE DROP AFTER URD MAF CAL INSTALL

So I Installed the MAF calibrator and thought everything was good.Truck ran good no check engine light but my mileage dropped 2 mpg.Checked
Eveything tapped the right wires so what did I do wrong.I had URD set it up for my mods.Could it be a bad solder job?

 

Most likely just a bad tune, unless they got your truck on a dyno, that preloaded tune will always be a little richer in fuel, running a little richer in fuel is better then leaner, kinda like a padding so you don't blow it all up, most preloaded tuning are setup that way so the customers don't blow their motors. They don't tell you that though.

Get on a dyno and have someone tune it that way you'll get the best air/fuel ratio for better MPG.

 

That's what I thought but wasn't sure.

 

True but tie tune should not be richer than the OEM set up.

How have you calculated your MPG? Instant reading? You have disconnect the battery so ecu has to relearn and set a bit.

Are you equiped to read AFR and datalog?

There is a procedure with the MAF to calibrate it. The closed loop part tuning is based on LTFT and STFT readings and can be done with the R4 software. Based on my experience each change of 0.1 in the map will produce a variation around 4% of the trim. Goal here is to have STFT + LTFT close to 0.

To calibrate the open loop part you need to be able to read and record TPS, AFR and RPM.

 

Hand calculated mileage and driving in closed loop most of the time.
Don't have equipment to read afe.
Thanks for the help.

 

What is the tune installed made for? I have a MAF Cali, installed several years ago, tuned for the URD CAI. My mileage didn't change noticeably at all.

 

Had on MAF calibrator afe si 2 intake tune.
But it's running rich in closed loop.

 

Might be one of your solders then, probably focus on the MAF sensor line. I had to solder my MAF sensor extension for the URD CAI. I have had issues with some bad solders that then cause the trims to start going rich. As soon as I fix the connections, trims go back down to small single digit trims. To be clear though, my issue is on the MAF sensor extension, not on the MAF Cali, but I suspect the symptoms would be similar.

 

That's what I'll look at next.
Thanks for the help.

 

How do you know you re running rich in closed loop? You said you dont have an AFR reading.

It can't run rich in closed loop. Your trims can be high but the result should be around 14.7

 

Most all driving I do in closed loop per ultra gauge and she seems sluggish.

 

Like said, check your fuel trims. But even with important negative trims, you cant run rich in closed loop. Just impossible and if the trims are too important you will have a check engine light.

Load R4 software, connect to MAF cali and read the map. Will be curious to see the value for the closed loop pat of the MAP. The cells values for the closed loop part of the map are probably 10 (neutral, 0 changes). But like said, at the insatallation you've disconnected the battery and it can affect the behavior of few factors like timing and transmission.

 

The 2 maps I have received from gadget have values of 10.1 & 10.2 depending on MAF voltage for closed loop.
I confirmed that adding fuel in closed loop got both my short term and long term fuel trim to close to zero.
When fuel trims are at zero or close it minimizes the amount of adjusting the ECU does when it references sensors and fuel tables and correct to add/subtract fuel to maintain AFR 14.7.
Because of refresh rate of sensors, reference of fuel tables, then correcting injector pulse width all take time there is a time delay before optimized mixture is achieved
My mileage has decreased as a result of setting a richer baseline, but I can notice the engine response is better
Also on a side note do you switch between gasoline grades?
Its winter time so winter gas blend reduces mileage as well.

 

What are your mods SO. Do you have a volant or K&N intake?

 

The truck runs lean from factory.
Mods include:
AFE intake
70mm throttle body
Intake manifold spacer
maf cal
NST pulleys
AFE shorty headers
Stock y pipe
vibrant 2.25 resonator
MTX-L and OT-2

 

The only area where my truck is running lean is at idle when stop or on park something like 14.9 to 15.1. In other CL conditions it's running pretty close to 14.7 must of the time. Sure there is some area where readings can be strange a bit cause 2 conditions happen like transition from CL to OL and at closed throttle form fuel cut to CL.

Very fun having the OT-2. I have an OT-1 and MTX-L , MTX-D. Do you get the cable to connect your MTX-L out to your OT-2?

 

Yea i got the cable to link them.
However I currently have not optimized my latest configuration.
I was using the URD Y-pipe with the extra bung for AFR readings but when I put the headers on I lost ALL back pressure.
So I put the stock Y-pipe back on.
Have not had time to get a bung installed and confirm latest mods are optimized for Powa

 

So far removed maf calibrator clean maf sensor but truck idle is high and goes up and down.Any ideas would be helpful.Sorry I haven't been on site lately but busy.no codes but truck started to run worse after removing maf cal.No codes throttle position per ultra gauge 16.9 %at idle.Thanks for all the help!