Paging all Powerlogger experts

[TurboBob]

Thanks for that input, Bob. I didn't realize there was a new version of the PL out. I'm confident in my install and don't see any instance where the wiring would get botched up.

For those of you following this thread, Eric is helping out over on his end as well. In summary, once the weather clears up, I will first test the readings and see if they've stabilized. I'm hoping that separating the TPS and the fuel transducer and giving them each their own circuit will eliminate some of the erratic readings. Once my new wideband sensor arrives, I will give that a shot as well. I'm suspecting a possible lazy sensor. In the meantime, I need to check the alky system again just to make sure it's output is up to standard...and then possibly the fuel pump.View attachment 213236

your signal wire is red? your 5v wire is green? thats a little non-standard, so I thought I'd ask....

B

 

[87geeinn]

your signal wire is red? your 5v wire is green? thats a little non-standard, so I thought I'd ask....

B

That's correct. Signal is actually orange (came with the sensor) and green is all I had in my electrical tackle box. Hell, it works for me.


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[broke]

Did you ever figure this out?

 

[87geeinn]

Okay, now we're getting somewhere:

While waiting for new wideband to show up in the mail, I pulled the wideband sensor and decided to have a look at the HBX-1 Innovate bung extender/heat sink and noticed it was almost completely clogged with carbon.

Put old sensor back on and went for a run. A little better but injector duty cycle and BLMs were still erratic and lean AFR spikes showing up on the logs. Then it started to rain...and has been ever since, until today.

Tested alky system over the weekend and it was leaking at the head and only putting out ~100-110 psi max. Put in my spare pump (new) and tested it. All good. In the meantime, new wideband showed up in the mail. Installed.

Went for two runs today and things are looking and feeling better. AFR is more stable, injector duty cycle is under control, and BLMs are not as erratic. I even bumped the boost up another 2 psi and got some decent tire spin on take off. However, I still don't like the looks of the erratic fuel pressure and still suspect the Accufab regulator. Sometimes it holds pressure after shutoff and sometimes it drops to zero. Also had to tighten the screw up over the weekend to get it back up to ~43 psi at idle. I just don't trust the damned thing. Put the "new" ball-seat style regulator on just for the hell of it and fuel pressure drops to zero within about 3 minutes, key off. Gonna order a Kirban regulator and try it out.

My diagnosis is, fouled wideband sensor due clogged bung extender/age of sensor (no error codes on the LC-1 anymore, BTW) AND leaking alky pump. Will do some more testing once Kirban regulator arrives. Screeshot below and full log attached.

 

[GNONYX]

You claimed the fuel "Sometimes it holds pressure after shutoff and sometimes it drops to zero"
I believe you might have an issue with an fuel injector not closing or is leaking.
Me personally, after engine shut down, the fuel gauge will hold the pressure for about 20 minutes or so before It starts to slowly reduce itself.

 

[krom]

I had the same symptoms when my regulator went bad, slow bleed down pressure then finally instant bleed down after turn off. New diaphragm fixed the problem.

 

[87geeinn]

You claimed the fuel "Sometimes it holds pressure after shutoff and sometimes it drops to zero"
I believe you might have an issue with an fuel injector not closing or is leaking.
Me personally, after engine shut down, the fuel gauge will hold the pressure for about 20 minutes or so before It starts to slowly reduce itself.

No...although I did consder this at one time. Back to back comparisons of two regulators showed very different results with pressure holding after shut down. Pressure holds all day long when I clamp the return line off at the front driver's side frame.

I had the same symptoms when my regulator went bad, slow bleed down pressure then finally instant bleed down after turn off. New diaphragm fixed the problem.

I inspected diaphragms on both of my regulators and they are not torn or leaking in any way.

In any event, I am feeling much more confident in the car. I accept the explanation given by another board member--in a different thread--who stated that there are just too many variables involved in regards to obtaining a good logging trace when it comes to fuel pressure (i.e., vibration, larger injectors, etc.). Now that my WOT BLMs and injector duty cycle are under control...and I have no knock, I'm pretty confident that things are good to go. Keep in mind that I had two major issues (leaking, weak alky pump AND a weak/fouled o2 sensor) that were fixed and showed expected results after fixing.

I can't say enough about how important the Powerlogger is AND the alky system test kit that Julio sells. IMO, Julio doesn't do enough to promote that product. It's a must have for his kit. I've found two leaky/weak pumps over the years with that thing that would have otherwise gone unnoticed.

 

[Fast4Ward]

I bought a new TTA fuel regulator off ebay for $50 not long ago and have thrown away 2 Accufabs in the past.

 

[TurboDave]

I'm still toying with the idea of pulling my accufab off and replacing it with a 237 (TTA regulator) regulator. Since I started using the more modern chips that allow direct manipulation of fuel, I haven't had to touch the fuel pressure regulator and a great many years.
The 237 regulators will generally supply a good 42-43 psi (line off) which is all that's needed for the base, and any changes in fueling can be accomplished via your chips or aftermarket ecm now days.

 

[TTA308]

That was my main concern with the accufab regulator, shut the eng. off and it would fall to zero within 3 sec., put old reg. back on and it would hold pressure for hrs., sent it back to accufab, when it come back same thing... anybody wants it i will sell it cheap...

 

[TurboDave]

That was my main concern with the accufab regulator, shut the eng. off and it would fall to zero within 3 sec., put old reg. back on and it would hold pressure for hrs., sent it back to accufab, when it come back same thing... anybody wants it i will sell it cheap...

I really wasn't trying to be funny, but rather serious.

 

[87geeinn]

I really wasn't trying to be funny, but rather serious.

I may just try the 237 regulator. Once I find a solution, both my regulators are going up for sale...with prominent disclaimers of course.

 

[BEATAV8]

Hey Gents I have some screen captures I'll post later.

Accufab regulator on my car is "OK" with it's pressure control but not perfect. I will be swapping it out to see if I can make it better.

On my wife's ride she has a modified stocker (233 with an adjustable aluminum cap). That one displays very steady fuel pressure.

 

[TTA308]

I really wasn't trying to be funny, but rather serious.

Sorry, hit the wrong icon.

 

[87geeinn]

For those still following, Julio chimed in on a separate thread which should prove interesting. Looky here: Yeah, right here.

 

[BEATAV8]

Stock (modified) regulator equipped car.....

 

[BEATAV8]

Accufab equipped car.....

 

[BEATAV8]

both use a Julio fuel pressure sensor setup

 

[TurboBuRick]

Interesting Steve...

Have you ever switched regulators car to car?

Rick

 

[TurboDave]

Interesting Steve...

Have you ever switched regulators car to car?

Rick

Excellent troubleshooting technique!! See if the problem follows the regulator or stays with the car.