Thanks for the suggestion. Since we are on the subject of an on car fuel system cleaning, has anyone tried the OTC 7448 type of set up where you force a cleaning agent into the fuel system schrader with the fuel pump disabled?

Thanks,

George

 

Awe, how do you run Seafoam thru the vacuum system?

 

Les

I have finally put together the capability to read cmp retard (CMP) using the BAFX bluetooth dongle from Amazon and Car Gauge Pro on a used Android tablet off of eBay. Some questions:

Which CMP do I use, there is a CMP* and CMP** with vastly different readings. Both are out of spec (-10, -28) so it looks like I have a distributor problem. I also have some random misfires shown on this set up which do not set any codes to discover from a standard code reader.

Can I force an idle RPM with this software and if so, how?

Once I get this straightened out I will get the fuel pressure readings that you asked for.

Thanks,

George

 

use CMP*

No way to control idle speed. That requires bidirectional control.

good luck and best wishes for a successful repair.

 

What's the most inexpensive way to get bidirectional control?

Thanks,

George

 

Least expensive one I know of is one of the softwares that I have.

HP Tuners VCM Scanner. Cost about $350. Don't know if it will let you to choose an idle speed but it does do the injector balance test where fuel is cut out once cylinder at a time and it displays the rpm drop from each cylinder.

 

You could always disconnect the iac motor and pull plug wires in a pinch if you want to know if a cylinder is contributing or not.

 

My CMP retard started off at -10.1. After loosening the distributor hold down bolt there was very little movement. I moved the distributor as far as it would go CCW and the best CMP retard I got was -8.5. Searching yields various suggestions:

Install V8 hold down
Enlarge the hold down hole
Replace the drive gear
Replace the whole distributor

What do you suggest?

Thanks,

George

 

After a series of life detours I am back at this. Rough idle is the issue. Today I got all of the fuel system measurements:

Pump on at the fuel rail - 62 psi
Pump off at the fuel rail - 56 psi
10 min later at the fuel rail - 55 psi

Pump on at the filter outlet = 83 psi
Pump off at the filter outlet - 82 psi
10 min later at the filter outlet - 63 psi


Lesmyer - Are you satisfied with these fuel pressure numbers?

The last time I worked on this I was only able to improve cam retard to -8.5. Today I was ready with my new distr gear, Mr. Gasket V8 hold down bolt and BAFX/Car Gauge Pro/Android set up but when I spooled up the diagnostics Car Gauge Pro won't communicate with the blue tooth dongle. Torque still works (but doesn't have cam retard) and the tablet says that its connected but Car Gauge Pro gives me an error message - "unable to connect. java.io.IOException: read failed, socket might closed or timeout, read ret:-1". I never had this problem when I originally used this set up. The internet has complaints about it but no solutions. I tried most of the usual reboots, disconnect/reconnect steps. Has anyone seen this and found a solution?

Thanks,

George

 

Seems to have zero problems with fuel pressure.

The device has to use two connections. First the tablet has to connect with the OBD2 device through bluetooth, and then the software has to initiate communication with the PCM in the Blazer. Sounds like the second part is failing.

In my experience, usually when Car Gauge Pro won't connect it is because something else is still connected using Bluetooth. Quite often I find that I have mistakenly not shut down Torque Pro and it is running in the background. Also I have found that the presence of other Bluetooth pairings like my phone to car audio and my phone to home theater sometimes seem to interfere. You may want to delete all Bluetooth pairings, and then redo the one for the OBD2 back in and try it.

I have had a couple of times where I had to pull the OBD2 adapter out and then put in back in to get a connection - but only with my new phone.

If Car Gauge Pro just won't work for you on your tablet, you can always go to Dash Command but it is a bit more expensive. You could also borrow someone else's phone and install Car Gauge Pro as a test. Just sign on to Google using your account, and then Google Play Store should let you download another copy for free.