No codes, power loss

[iamdub]

The MAP (Manifold Absolute Pressure) sensor could be faulty, but I'm talking about the MAF (Mass Air Flow) sensor. The MAF is in the intake air tract and can be affected by buildup of dirt/oil. The MAP isn't in any real danger of this, but can still cause drivability problems. Again, all of this could easily be checked by competent use of a scan tool.

 

[jfoj]

OK, Android, this is helpful because there are some small variations between Android and iProducts.

I would hold off on chasing sensors, even a "dirty" MAF should have been obvious to a decent mechanic. I rarely find "cleaning" a MAF does anything else to improve things. Some MAF's may benefit from cleaning in some situations, but they are rare situations.

Try to get a DropBox Free account set up while you are waiting on the interface, this will save a bit of time.

I will try to post some info about setting up the App and Interface. In general the first thing that needs to happen is the Phone and Interface need to be Paired via Bluetooth. I hope whoever is on the side with the phone and vehicle is willing to work with the initial set up. Once the App is set up things are pretty easy from there.

 

[jfoj]

So something for you to think about and I am testing this out now.

If you/whom ever owns the Android device is comfortable allowing me to remotely connect to the device. I may be able to do a lot of the background work in setting up and viewing data from the vehicle.

This is using a commercial remote access program and the end user has to launch the Remote Connection App, provide me a ID number then they have to allow me to connect.

Just something to think about because I assume the person driving the vehicle is not so technical savvy and may not understand how to do a lot of the things needed to get everything set up.

 

[blackhawk17]

She got the Veepeak and hooked it up, I got the Dropbox set up, and she ran it last night to see what came up. She didn't drive it, just let it sit at idle while we talked. Everything seems to work fine, only the log file it sent to Dropbox only consisted of time, lat/long, and vehicle speed.

I don't know if that was because she was only sitting at idle or if setup needs to be changed.


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[jfoj]

There is a bit more to it that just connecting the tool up unfortunately. This will hopefully change a bit in the future.

Here is some more info, you may want to forward this on or have her come view the info here. It takes some time to find your way around the tool.

Hopefully this does not scare her off!!! One thing I need to make clear up front, it this data is not 100% vetted for the GM V8, there may be some small tweaks we need to make for the PID's to Log.

You need to learn how to use the Logging function, this is the most useful part of the tool. It allows people like myself to see what is going on with the car and saves 40-50 posts on each thread. Every time the App is connected it is Logging.

So here is some information that may be useful. But you also need to spend 20 minutes playing with the App. Please note anytime you perform a Diagnostic Report, please have the engine running.

Read this in detail:

OBDFusion is FAR more intuitive than other Apps.

First change the MAF reading from Pounds/Min to Grams/Sec, stupid EASY.

Settings, Units, Airflow menus, choose g/s.

Temp sometimes can be more useful in C vs F, but no so critical.

Settings, Log Setup then set the following:

Logging Enabled - checked

Logging Trigger - choose Trigger at a fixed sample time

Sample Time - choose 1000 msec

Log GPS Items - suggest you unselect it as to not advertise where you live

Select Items to Log - This varies a bit for each car. But here is a list I like to see:

Fuel - do not check any of these 3 items

SAE PID's:

Fuel system 1 status
Fuel system 2 status
Calculated load value
Engine coolant temperature
Short term fuel % trim - Bank 1
Long term fuel % trim - Bank 1
Short term fuel % trim - Bank 2
Long term fuel % trim - Bank 2
Engine RPM
Vehicle speed
Ignition timing advance for #1 cylinder
Intake air temperature
Mass air flow rate
O2 Voltage (Bank 1, Sensor 1)
O2 Voltage (Bank 1, Sensor 2)
O2 Voltage (Bank 2, Sensor 1)
O2 Voltage (Bank 2, Sensor 2)
Input Voltage read by the scan tool

Before any codes are cleared, get the Freeze Frame data and email or save the screen shot if this is an option. Freeze Frame data saves about 20+ questions as to what is going on.

Once of the most useful things is a Diagnostic Report. This needs to be run and uploaded to DropBox. This feature can be found under Diagnostic, Reports. The "Report" tab is not always visible depending on the device you are using. A Right to Left screen swipe may be required or just turn the phone/tablet from portrait to landscape to find the "Report" tab on the top right. Once you find the "Report" tab, touch it and this will run a Diagnostic Report. I need the Diagnostic Report run while the engine is running, helps if the engine is warmed up, but does not need to be fully warmed up. SPECIAL NOTE, there will be a warning that pops up about not running the Diagnostic Report while the engine is running, ignore this warning, and run the Diagnostic Report nothing bad will happen, this is just a Liability cover for the App developer. The report may take as long as 30-45 seconds to run, it will be obvious when it is complete because under the PID Snapshot there will be something like 20 PID found.

I HIGHLY recommend to Save the Report before it is uploaded to DropBox just in case there are any problems. Touch the floppy disc icon to save the report. I do not recall if there is an acknowledgement that the Report was saved.

I like to see 3 baseline Logs.

Cold start from overnight. Turn ignition on and get App connected before you start the engine. Start the engine and let it idle for 5 minutes in Park or Neutral, do not touch the throttle. After 5 minutes, disconnect the App to stop the Log so it is not too large.

Warm idle for 4 minutes. You can connect the App while the engine is running, the disconnect the App after 4 minutes.

Warm highway cruise fro 4 minutes. Try to find a flat/level road without much traffic. 50-65 MPH range, hold as steady as possible and/or use cruise control.

After you get the Logs, upload them to DropBox and long with any screen shots or Diagnostic reports. Then choose the Share option in DropBox, then copy and paste the URL back in the thread for my review.

 

[afpj]

I wouldn't consider replacing the fuel pump a waste especially if it was the original. It was a ticking time bomb (or dud/UXO if ya know what I mean). As far as trying things starting cheap, cleaning the MAF with MAF specific spray couldn't hurt, may actually help, if done properly. (this is the only point I somewhat disagree with jfoj). Otherwise as has been said, look at fuel trims...could help diagnose a vacuum leak, O2 sensor failing etc. Good luck

 

[jfoj]

Fuel Trims will give a good idea for MAF behavior. But if the vehicle has been reasonably maintained with a air filter changes, not run without an air filter and not run with the oiled cone style air filter that may have been over oiled, usually the MAF will be clean.

You can clean it, does not cost much, but every one of my 6 vehicles, as old as 20 years old have never had the MAF cleaned. I find MAF cleaning an Internet sensation propagate typically by people grabbing at straws that have no real automotive diagnosis and repair ability that are looking for a "Mechanic In A Can" solution.

 

[afpj]

I have several "mechanics in a can" LOL. I thought I read that the OP did have an oiled air filter.

jfoj, are you partial to OBDfusion over Torque, or they about the same? trying to edumicate myself. thx

 

[jfoj]

I have several "mechanics in a can" LOL. I thought I read that the OP did have an oiled air filter.

jfoj, are you partial to OBDfusion over Torque, or they about the same? trying to edumicate myself. thx

I thought I had read the OP might have an oiled air filter, but this by itself is not necessarily a death sentence for a MAF. Although I may be somewhat new around here, I deal with A LOT of different forums, both Foreign and Domestic and I have been for a LONG time. I try not to commit every vehicle and problem to memory because I just do not have the storage capacity to keep every single detail for every forum post straight.

So as for OBDFusion and Torque, here is the story.

1. Torque was one of the first lower cost Android OBDII Apps available, in the early days, this was an App I used and would recommend. BUT like anything, time had allowed other Apps to be developed. I found a number of bugs and short comings with Torque and over time found that there was no easy way to provide SOLID feedback to the Torque developer. All feedback had to go through the Torque Forums. For the record, I am not OBDII or Scan tool novice, I have more money tied up in OBDII and Scan tools as well as software than most people have in one or more of their vehicles. I provide feedback to consumer grade OBDII tools and Apps as well to the big name Profession level 5 figure scan tool vendors.

So after finding many bugs with Torque and then working with OBDFusion (formerly known as Touch Scan), I found the OBDFusion developer was VERY open to feedback, both positive and negative. I also found that the OBDFusion developer was usually pretty quick to incorporate fixes, changes and new feature requests. Then I found that the OBDFusion App price was dropped to $1 below the Torque App, so it became a NO BRAINER. Then the OBDFusion developer ported his to iProducts/iOS, then there was finally a consistent and low cost OBDII App that operated on the 2 primary phone/tablet platforms that are available.

I continue to provide feedback to the OBDFusion developer and as recent as the 4.0.0 release there are features requested that were added. At the moment the developer has added Ford/Mazda Enhanced Manufacturer support and is currently working on Toyota. These Add-Ons are $10 for each model year for each manufacturer which is a pretty good deal for a DIYer that will give you up to 650 PID's covering all major systems on the vehicle.

NOW the bad news, not sure GM will be supported by OBDFusion anytime soon. GM wants like $50k to put your toe in the water, then they have like a $5k annual commitment. If you ever decide to not renew the annual commitment, then you have Licensing issues where you then have to removed any GM support you have ever added for your product!!! This kind of makes even Apple look tame in comparison to GM.

But anyway, hopefully you understand my preference for OBDFusion, first it is $1 less than Torque, less bugs, developer is open to feedback and quickly resolves bugs or adds new features, the same App is available for iOS and there is some Enhanced Manufacturer support for some product lines.

 

[blackhawk17]

1. Yeah, I actually meant MAF sensor the other day, irrelevant at this point.

2. The settings have been adjusted, not exactly per your suggestions listed above, but I'm working on it.

3. I do have a CAI with a conical oiled air filter. However, this issue was present before I had my mother clean the air filter. So I'm going to assume she didn't over-saturate the filter per my request.

4. I have Dropbox set up already, and have already seen several reports of GPS position and speed, and nothing else. Hence, I had her go into the log setup and add basically everything for now until I figure out what actually gets sent, what is needed, etc. Of course it looks like you just told me. I'm just waiting for more log files. I basically get a notification on my phone every time she drives, which is kind of funny.

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