Yet another EFI help thread :/

[dakinez]

5 minutes ago, siteunseen said:

Sounds like the valves are too loose or the timing is low, maybe both?

vacuum looks okay though.

You mean ignition timing right? I'll do it again tonight, but it was right at 10 degrees. Here is a video from last week.

 

[siteunseen]

3 minutes ago, dakinez said:

Thanks for this, I'll check it. I did go through all the EGR equipment as much of it had been removed by the PO and the car barely ran at all back then. But I don't remember checking that, so I'll make sure.

I did notice I have tiny exhaust leak from cyl #6 where the manifold bolts up to the head, the last bolt is missing; so i need to fix that but I don't feel like it's the cause of this current condition. 

Here's a picture I just saw in another thread.  The tube connects to where the circle is.

[siteunseen]

Is that 10 degrees at idle with the distributor's vacuum advance hose plugged?

I don't know what it is but something is clicking like crazy?  

[dakinez]

1 minute ago, siteunseen said:

Is that 10 degrees at idle with the distributor's vacuum advance hose plugged?

I don't know what it is but something is clicking like crazy?  

Yes 10 degrees at idle but I realize that I did not remove & plug the dist vacuum line :/

I was hoping the ticking was just the injectors (and normal), I've not been able to track it down between injectors and valve cover. It could be valves. i guess I should check them too.

[Zed Head]

I think that the ticking is just injectors, amplified a bit by the camera.  You shouldn't have to plug the vacuum hose to set timing, but it will allow you to get a better view of how the mechanical advance in the distributor is working.  Your timing mark didn't move much when you revved the engine.  Vacuum advance is normally on a "ported" vacuum source, which means it's closed when the throttle is closed.  As soon as you open the throttle you should get a big bump in timing.  Yours barely moved.

The engine actually sounds pretty good to me, at idle.  Your idle is high though, suggesting a vacuum leak if you haven't turned it up yourself.  I would let it idle and turn the idle speed down using the screw on the throttle body.  See what happens then.  If you can't keep it running because the fuel pump switch in the AFM keeps opening it's another sign of a vacuum leak.  People find vacuum leaks everywhere from the injector o-rings to cracks in the throttle body intakes hoses.  Your vacuum readings are another sign of a vacuum leak.  Pretty big, because the small ones don't usually show uo in intake vacuum.

Add up all of the small stuff and it says vacuum leaks in the intake system.  Keep looking.  Check that PCV hose under the intake manifold.  That's a common failure and it's connected to the intake system.

[Reptoid Overlords]

I hear quite a bit of valve chatter.  you are supposed to be able to hear the valve train when they are adjusted properly, but to me yours sounds a bit loud, like they are lose like siteunseen said.  Vacuum at idle should be around 17 or 19 HG at least, depending on your elevation.

Edit: if they say it's probably injector noise we're hearing i'd go with that as opposed to my valve noise suggestion. I have that same vacuum tester and as far as i can tell it's pretty accurate. 

Edited March 19, 2018 by Reptoid Overlords

[Zed Head]

Really though, what we should be pointing out, is that adjusting the valve lash is the very first item in the Engine Tuneup chapter.  It's the messiest, most difficult thing, but it's the most important.  If you know lash is correct then the noise doesn't sound so bad.

Forgot to say, a sticky valve can cause intake popping also.  As can a damaged cam lobe.

Edited March 19, 2018 by Zed Head

[dakinez]

This is great stuff, thanks for the direction.

The PCV hose was replace by the PO. It's actually two hoses, one inserted in to the other. When i got the car it has some kind of goo *sort of* sealing them together. I cleaned all that up and used a bonding cement. I'm confident that one is good, but I will go through all the vacuum lines, the throttle body boot, etc again, and get down under the intake too.

Do you agree that even if the valves could use adjustment, it wouldn't be the cause of this poor running?

[dakinez]

5 minutes ago, Zed Head said:

Really though, what we should be pointing out, is that adjusting the valve lash is the very first item in the Engine Tuneup chapter.  It's the messiest, most difficult thing, but it's the most important.  If you know lash is correct then the noise doesn't sound so bad.

Forgot to say, a sticky valve can cause intake popping also.  As can a damaged cam lobe.

Hah, that answers my other question! I hate valve adjustments

[siteunseen]

This helps me on the valves, make a card showing the 6 intakes and 6 exhaust.  Usually two will be up at the same time and I just X them off as I go.  A mistake I made on the Z was pointing the lobes straight up when the motor is actually tilted to the passenger's side.  I put straight lines on the center of the cam towers and go by those.

Put the card under the passenger's side wiper blade.

Edited March 19, 2018 by siteunseen

[dakinez]

6 hours ago, siteunseen said:

This helps me on the valves, make a card showing the 6 intakes and 6 exhaust.  Usually two will be up at the same time and I just X them off as I go.  A mistake I made on the Z was pointing the lobes straight up when the motor is actually tilted to the passenger's side.  I put straight lines on the center of the cam towers and go by those.

Put the card under the passenger's side wiper blade.

 

I made a copy of your card, great idea!

[dakinez]

I spent another hour on this tonight, here's what's new.

The ticking is absolutely definitely from the injectors. I proved this using the highly scientific screwdriver method (sharp end on the component, plastic end on my ear). The valve cover just has some soothing swirly gurgling sounds, on the injectors I can very clearly hear the individual firing of each one (addictive actually :). Of course just because they're firing doesn't mean they have a good spray pattern etc, but that particular mystery is solved. It sounds more severe in the video than it does in person. On that basis, I'm going to save the valve adjustment for another day. Agree?

I had a really good look under the intake, all around the both manifolds, all around the connection for the EGR etc, it's actually really clean and appears to be in really good order. I don't see any evidence of any leaks around it. I *think* it's good, but I will try and find some kind of smoke generator; I'm not a big fan of spraying starter fluid down on the exhaust manifold.

I checked the timing (properly this time - removed and plugged the distributor vacuum). It sits right at 10 degrees BTC when steady, moves as far as 20 degrees under acceleration, then drops back to 10 under deceleration. Am I right in thinking that is just where it needs to be?

Hard to see in the video, but its there. 

 

 

 

Check this out though. I pulled the AFM boot off to check it, you know how it goes, keep pulling things off :/ Well i decided to check the resistance of the AFM through it's stroke. Have a look at this video. It jumps substantially. Would you agree that it shouldn't do that? It ranges from 38 ohms resting, and peaks at around 572 ohms about 3/4 through, but jumps all over the place. Could that be sending whacky signals to the ECU?

 

 

Edited March 20, 2018 by dakinez