I took a quick look when I downloaded it.

It appears you turned the key to "run", started the data logging, but never tried to start the engine. You left it for 81.5 minutes, and all it did was run the battery down from 11.4 volts to 3.3 volts.

Not much to see with that approach. At least need to see what happens when you try and start the engine, and if it starts, let it run until it stalls, or follow the guidelines in post #2 of my scanning guide thread. When the engine shuts down, stop the data log.

https://www.camaroz28.com/forums/com...-guide-886891/

The limited info:

You have DTC 29 for the AIR pump. If the pump has been deleted or disconnected, it's easy to eliminate the code.

You also have DTC 48 for the MAF sensor.

Your IAT sensor appears to be disconnected, because it's reading -40-degF.... 40-degrees below 0.

Everything also seem normal for a non-running engine. The "knock counts" are increasing rapidly, but in all honesty, I have never observed knock counts for 81+ minutes on a non-running engine.

The PCM is receiving the fuel enable signal from the PASS-Key II (VATS) system, so that's not the problem.

 

Ok, I am very new at this. I will do what you recommended and re-post. Thanks

 

This file should be better. The car was a bit warm. but still stalled out.

 

DTC 29 for the AIR pump. Did you delete the AIR pump? If the pump is still there and hooked up, check the fuse. If it's burned out, replace it. That will clear the code. If the fuse blows again, unhook the pump, then replace the fuse and don't hook the AIR pump up.

DTC 48 for MAF sensor. The problem with the engine is it's struggling to get enough air. It has opened up the idle air control (IAC) valve as far as it can go (160 counts) and it's still not getting enough air. But it's running very rich at times, and in the end, the excessively rich condition causes it to stall. When the MAF sensor is faulty, the PCM defaults to speed-density, a method of calculating mass air flow, using the manifold absolute pressure (MAP) sensor and intake air temperature (IAT) sensor. This just complicates the entire procedure.

Fix the MAF sensor. put a good fuse in the AIR pump circuit. See if this helps. Also, check the idle air control (IAC) valve on the throttle body. The pintle could be dirty, the air passage may be crudded up. If the IAC pintle is dirty, clean it with something like MAF sensor cleaner, and a soft brush or Q-tip. Do not move the pintle, hold the pintle facing down so no fluid enters the electronics. There is a delicate motor that moves the pintle in and out. Check the resistance of the sensor, per Shoebox: Try blowing compressed air through the IAC air inlet to make sure it's clear. In extreme cases, the gasket on the bottom plate of the throttle body can allow coolant to leak into the IAC passage.

http://shbox.com/1/iac2.jpg

Just for the heck of it, check the air filter to make sure it isn't plugged up.

 

This is good, im glad you found something, thanks for the help thus far. I did have trouble with the air box wiring. I had to re-do the 3 terminals, im guessing i didnt hook them up to the right spot.
You suggested i fix the MAF sensor. Besides washing and cleaning, what is there to fix?

 

The codes may be what is causing the fans to turn on prematurely.



DTC 48 sets when the PCM is receiving no signal at all from the MAF sensor. The signal from the MAF sensor is a variable frequency. The frequency varies from about 2,000 Hz at idle to about 12,500 Hz at max flow. The air flowing through the sensor removes heat from the wires/resistors (Wheatstone bridge). The electronic module in the sensor calculates the energy required to maintain the wires/resistors a fixed number of degrees above the incoming air temperature It converts this energy value to a frequency, The frequency "rides" on a 5 volt signal between terminals "A" and ground. The PCM has a table that converts the frequency in Hertz to mass air flow in grams/second. The code sets when the PCM sees reference pulses from the Opti, but does not see any activity from the MAF sensor.

Could be:

- faulty harness wiring
- bad contacts in harness connector
- damaged wires/resistors in sensor grid
- failed electronics module in sensor

Harness off sensor, check the pins in the harness connector:

- 12 volts between pins "B" and "C"
- 12 volts between pin "C" and chassis ground
- ~5 volts ( 4 to 6 volts range acceptable) between pins "A" and a ground

Pin designations are shown here (from Shoebox):

http://shbox.com/1/1995_pcm2.jpg

To check the MAF sensor output, if you have a multi-meter than can measure frequency, reconnect harness, start engine and measure the frequency between wire "A" and an engine ground. At idle you may see anywhere from 2,000 - 2,500 Hz. Revving engine should cause frequency to increase.

 

Just as a heads up. I took all the parts apart and cleaned them and the connections. Put everything back. Started it up it revved to 3,000 non stop. I had to shut it down because it was to late and to loud. I tried the next day and it wont start. It turns over strong but not even a hint of a spark. Re-did all my previous work and got the same result. I did not put a meter on it yet. I apologize for the long timing between posts. I am still trying to fix this. I really need to get running so i will see this through to the end. Would you like a scan of it turning over?

 

Just scan it for codes.

 

And check for spark, at the plugs. If you have spark, check the fuel pressure.

 

Here is the no start file. And the car has no spark. Thanks

 

You have DTC 41 for “Ignition Control Circuit (open circuit)”. That’s the white wire that runs from the PCM to the ICM. That wire is how the PCM tells the ICM to fire the coil to produce a spark. Use the first part (ICM Harness) of Shoebox’s procedure to check that circuit, 12 volt power to the ICM, and ground for the ICM. I gave you the link to that procedure back in post #11, but here it is again:

4th Gen LT1 F-body Tech Articles

No need to check the 2nd part (Optispark Harness) because there is an RPM reading in the log, and that comes from the Opti. No problem there.

You now have DTC 22 for “Throttle Position (TP) Sensor - (signal voltage low)".. Might be disconnected or wires shorted.

And you still have the codes (DTC 29) for the AIR pump and (DTC 48) for the MAF sensor. I’ve explained how to troubleshoot both of those.

I have decided that it isn’t worth my time and effort to review these data logs any more. One of the reasons is that many people don’t follow up on my suggestions. Or the thread drags out with no feedback. This thread is a prime example of the problem. Sort out the ICM and MAF. Investigate the TPS and the AIR pump. The last two aren’t likely to be causing your problem, but they need to be corrected.

 

Sorry my busy schedule didnt fit your open free schedule. Life gets in the way and apparently that isnt acceptable on this board. Guess i will just start throwing parts at it. This is the first time i have ever seen someone deny help on any board, (specially car guys, always helpful) we usually stick to it and help until the end, your choice.

Would any other readers like to help out with this issue. IM more than willing to throw out a amazon gift card or something for the help. Much appreciated.

 

I gave you repeated help, including several suggestions in my most recent post. But you chose to ignore it, and responded with an immature hissy fit. I'm really disappointed in your failure.

Good luck…. You're going to need it.

PS: I made the decision LAST MONTH to stop reviewing data logs for EVERYONE, and posted this info and the reasons. You were not singled out, but your reticence was a contributor to my decision. You helped ruin it for EVERYONE.

https://www.camaroz28.com/forums/com...1/#post7008507