Engine Cuts out and stumbles under boost...HELP PLEASE! `

I meant Air Fuel Ratio. I should have said Wide Band not AF

No trees were harmed in the sending of this message, however, a significant number of electrons were terribly inconvenienced.
 
I had a PL cause some issue like you are seeing. If you take it out to wire some stuff maybe take a quick lap without it.
 
He already has an autometer gauge (did a incorrectly assume electonic?). If so just tap into the signal wire (purple wire i believe but check) and run it to an analog port on the PL board and set it in PL for 100psi sensor

No trees were harmed in the sending of this message, however, a significant number of electrons were terribly inconvenienced.
 
On the Data tab you can see ECM AFR and it is definitely leaning out. Now I am beginning to question my eyes and my memory! I know the FP was rising with boost however I must not be seeing enough detail on the gauge because the AFR is definitely plummeting during the "event"
 
achalmersman said:
He already has an autometer gauge (did a incorrectly assume electonic?). If so just tap into the signal wire (purple wire i believe but check) and run it to an analog port on the PL board and set it in PL for 100psi sensor

No trees were harmed in the sending of this message, however, a significant number of electrons were terribly inconvenienced.
Click to expand...

you assumed correctly, it is an AutoMeter electronic gauge. I will run a wire to the board in the morning.
 
Nero328 said:
On the Data tab you can see ECM AFR and it is definitely leaning out. Now I am beginning to question my eyes and my memory! I know the FP was rising with boost however I must not be seeing enough detail on the gauge because the AFR is definitely plummeting during the "event"
Click to expand...
The o2 volts move down and up because the IDC is moving down and up. The ECM is rapidly changing the duty cycle of the injectors and the o2 sensor sees the changes in o2 levels. The question is what information is the computer being given that is causing it to make the rapid changes to IDC. The exhaust gasses aren't going lean because the fuel system isn't sending enough fuel to the fuel rail. The lean condition exists because the computer is shutting down the injectors.
 
Ttype6 said:
The o2 volts move down and up because the IDC is moving down and up. The ECM is rapidly changing the duty cycle of the injectors and the o2 sensor sees the changes in o2 levels. The question is what information is the computer being given that is causing it to make the rapid changes to IDC. The exhaust gasses aren't going lean because the fuel system isn't sending enough fuel to the fuel rail. The lean condition exists because the computer is shutting down the injectors.
Click to expand...

I follow you with that logic and it does make sense...what could cause the ECM to shut down the injectors? There is a strange spike in the duty cycle of the injectors during the event too.
 
What am I missing? I can't see where the EGT's are shown in the data. I see EGT but it is showing a constant 33 degrees which is obviously wrong. I do have an EGT gauge but I dont think it is being logged by the PL...that is something else I can tap into it tomorrow as long as I have a couple of empty slots on the board. I dont know how many it offers.
 
Nero328 said:
There is a strange spike in the duty cycle of the injectors during the event too.
Click to expand...
And RPM. The RPM shouldn't change 800 rpm from one frame to the next.
The rpm that you see in the log is the engine speed information that is being given to the computer. The IDCs that you see are the changes being made by the computer to the on and off injector times based on that and other information. The computer is being fed some very erratic engine speed information and it is making some very erratic adjustments based on the information it is receiving.
 
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Nero328 said:
What am I missing? I can't see where the EGT's are shown in the data. I see EGT but it is showing a constant 33 degrees which is obviously wrong. I do have an EGT gauge but I dont think it is being logged by the PL...that is something else I can tap into it tomorrow as long as I have a couple of empty slots on the board. I dont know how many it offers.
Click to expand...
Nothing wrong with monitoring EGT,but it's not a priority. The very first thing I would do tomorrow is test the cam sensor. No wiring involved.
 
Ttype6 said:
And RPM. The RPM shouldn't change 800 rpm from one frame to the next.
The rpm that you see in the log is the engine speed information that is being given to the computer. The IDCs that you see are the changes being made by the computer to the on and off injector times base on that and other information. The computer is being fed some very erratic engine speed information and it is making some very erratic adjustments based on the information it is receiving.
Click to expand...

The computer is getting the RPM signal from the crank sensor right? I changed that for a brand new one while I was in Phoenix (courtesy of Nick!! Thanks!) just to see if that would make a difference...it didn't.
 
Nero328 said:
What am I missing? I can't see where the EGT's are shown in the data. I see EGT but it is showing a constant 33 degrees which is obviously wrong. I do have an EGT gauge but I dont think it is being logged by the PL...that is something else I can tap into it tomorrow as long as I have a couple of empty slots on the board. I dont know how many it offers.
Click to expand...

I believe you will need an egt amplifier to log egt with the power logger. I like egt for tuning, but wide band AFR is probably easier to get things cleared up for now.


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Ttype6 said:
Nothing wrong with monitoring EGT,but it's not a priority. The very first thing I would do tomorrow is test the cam sensor. No wiring involved.
Click to expand...

Yeah I will definitely do that in the morning however I don't want to do another log run without FP being logged so I might as well wire up the EGT at the same time, it will only take a few minutes and I will be under the dash anyway. I am trying to keep these test runs to a bare minimum because it is definitely leaning out and I don't want to hurt the motor or at a minimum hurt another head gasket...I hate having to change out head gaskets, there is so much involved just for 10 minutes of having the heads off to change the gasket.
 
captrob said:
I believe you will need an egt amplifier to log egt with the power logger. I like egt for tuning, but wide band AFR is probably easier to get things cleared up for now.


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Click to expand...

Unfortunately I can't afford a wideband right now...I am tapped out and have WAY more money in this car than I care to admit, it is embarrassing really! So running an EGT signal to the PL board won't work? I do have a memory gauge, I wonder if it already has an amplifier in it in the module?
 
"(didn't die but just lost all power)"

Lots of suggestions here, but have you bothered to make sure the battery connections are tight?

Terminals are tight, Pos Batt to starter with no possibility some sort of grounding are verified, Neg Batt to Fender is tight, etc........

And really one stupid, but very valid question.... Is the coil pack cinched down tight on the module?

I'm just askin'.
 
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TurboTGuy said:
"(didn't die but just lost all power)"

Lots of suggestions here, but have you bothered to make sure the battery connections are tight?

I'm just askin'.
Click to expand...

LoL...yeah they are tight both power and ground. I laugh because you never know who you are dealing with when you are helping people out on these boards so I don't take any offense to the question at all. I have helped people before and spent countless hours trying to help diagnose something and then find out its out of gas or something stupid like that.

Yes, I have checked all of the grounds and the battery cables and the wiring at the starter and alternator. Please keep the suggestions coming!
 
I added one to my OG post... coil pack cinched down......

Chased it for about a month.......


RRRRRRR shift, WTF... RRRRRRRRR shift WTF...... And so on.
 
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