3FE Head Gasket (2 Viewers)

[Rush]

First fuel pressure tester adapter sheared off while threading into fuel rail.
Have new test kit now, 58 PSI while cranking/key on with Fp jumped.
Dropped to 38 PSI within about 10 mins, it's at 20 PSI now, ~14.5 hours later.

Curious, though... The gauge reads 14 PSI sitting disconnected, like it's an absolute measure of pressure, not relative. Should this be that way?

I doubt that's supposed to be the case, I'll call and see if the other fuel pressure test kit reads 14 disconnected.

Either way, the FPR did flow more (less PSI on the gauge) once I applied vacuum to its hose.

Depending on the gauge's health it's either perfectly in spec, or 14PSI above, which implicates the FPR. Good thing I have another old and potentially broken one to swap in in case.

I'll report once I know.

Yeah, s***'s ****ed. The other kit reads 0.
Swapping the tester out now.

 

[BILT4ME]

Yeah, s***'s f***ed. The other kit reads 0.
Swapping the tester out now.

Damn!

You are having some of the toughest luck with simple things and tools not working right!

 

[Rush]

Damn!

You are having some of the toughest luck with simple things and tools not working right!

I appreciate the commiserating, man.

It's been rough, but it's all good. The wife has no hope the truck will ever run, but still allows me to think it will.

 

[Rush]

Ok, updated pressure figures:
~48 PSI with key on, and Fp jumped to B+.

5 mins later it's at ~34 PSI, which passes the sniff test:

Which means that the FPR isn't likely the culprit.

According to Mr. T's diagnostic tree, this points next to the AFM.

Onward!

 

[Rush]

Oh, and also... I put 10 gallons of fresh gas in yesterday, as well as a can of seafoam and a bottle of heet.

The truck's been sitting for 10 months, I call that old of gas bad. So it's 50/50 good and bad, with about $13 of hopeful additives thrown in to exorcise the bad humors from the afflicted soul.

 

[Rush]

AFM checks out per the FSM.
With the key on, opening the airflow door starts the pump going, btw.

Next, spark timing.

 

[Rush]

Starting fluid gets it up off the ground, but it can't stay up. It refuses to idle.

I'm thinking clogged injectors from the old fuel?

Will keep monkeying with timing and see.

 

[Rush]

Got it to almost idle.

Getting close!

 

[BILT4ME]

Starting fluid gets it up off the ground, but it can't stay up. It refuses to idle.

I'm thinking clogged injectors from the old fuel?

Will keep monkeying with timing and see.

Everything with that points to the VAF or AFM to me. Jon Held has coached a couple others through an issue such as this. You have already done your diagnostics.
Fuel pump is good and holding pressure
You have spark
You have airflow
It WILL start

It's not getting fuel. Why? The computer is not telling the injectors for some reason. I am guessing the AFM is not seeing the vane movement, indicating operation.

He had another guy disconnect the AFM and try to start. It would start, run for a moment and die. That pointed directly at the AFM.

The other thing IMO would be the TPS.

 

[Rush]

Everything with that points to the VAF or AFM to me. Jon Held has coached a couple others through an issue such as this. You have already done your diagnostics.
Fuel pump is good and holding pressure
You have spark
You have airflow
It WILL start

It's not getting fuel. Why? The computer is not telling the injectors for some reason. I am guessing the AFM is not seeing the vane movement, indicating operation.

He had another guy disconnect the AFM and try to start. It would start, run for a moment and die. That pointed directly at the AFM.

The other thing IMO would be the TPS.

Testing now!

 

[Rush]

Testing now!

same result. I'll set dist timing bank to center and try again. Maybe with the 7btdc jumper as well.

 

[Rush]

Testing the ISC, I don't recall hearing any clicks.

 

[Rush]

Testing the ISC, I don't recall hearing any clicks.

Zero movement of the ISC when pins grounded. Spark, yes, but no movement.

Replacing with the other (original) intake's ISC. After testing it.

 

[Rush]

Zero movement of the ISC when pins grounded. Spark, yes, but no movement.

Replacing with the other (original) intake's ISC. After testing it.

Tested both off the truck, same behavior. The motor will vibrate when I rattle the grounding connector between the pins to move it, but it doesn't go closed. Just a millimeter of movement.

 

[Rush]

Also, no A/T or charge lights.
I just noticed those on @jonheld 's EFI diag sheet.

Are those indicative of an issue in this area?

 

[Rush]

Having stepped away a bit...
1. I haven't confirmed zero vacuum leaks.
2. I'm having luck running when I add more fuel.
3. It almost idles on its own, and almost starts on its own.

Vacuum leak?
Other A/F ratio issue? The O2 sensor harness looked iffy when I plugged it in to the new harness, when in the startup/idle process does the ECU such to using the O2 reading?

The injectors could be gummed up from old bad fuel since installation/attempts to start... But they could also just be in s***ty shape. I cleaned them in my ultrasonic with simple green while pulsing, for ~30 mins each, and then flowed carb cleaner through them at differing pulses.
But... Witchhunter, I am not.

Either way, vacuum needs confirming.

 

[ppc]

Exactly how are you able to "add more fuel"?

 

[Rush]

Exactly how are you able to "add more fuel"?

Starting fluid into a breather hose on the big intake hose, then crank.
Starts, revs with pedal, dies.
Idle seems to be the challenge.

 

[Rush]

Everything with that points to the VAF or AFM to me. Jon Held has coached a couple others through an issue such as this. You have already done your diagnostics.
Fuel pump is good and holding pressure
You have spark
You have airflow
It WILL start

It's not getting fuel. Why? The computer is not telling the injectors for some reason. I am guessing the AFM is not seeing the vane movement, indicating operation.

He had another guy disconnect the AFM and try to start. It would start, run for a moment and die. That pointed directly at the AFM.

The other thing IMO would be the TPS.

I'll retest the TPS, too.

BUT:
I do not have this:

I have this:

 

[Rush]

Here's a video of what it does with starting fluid in the intake:


And what it does without starting fluid: