Want to be

Items i worked on so far.

Checked MAF resistance and voltage (before and after driving) All OK.
1. Was rebuilt by JDS. I dont' know when though.
2. checked hot wire. (video)


Replaced 02 sensor
1. improved but still running to rich

Vacuum video before engine rebuild
(notice a constant vacuum)

Vacuum video after engine rebuild, (after 02 replaced too)

I noticed a quick vacuum post and then displaying nothing. Im guess i have a decent size vacuum leak.

Please note, i checked the vacuum after a 40 minute drive. I did not notice the vacuum gauge actual displayed a value until today while watching the video. Im glad i had my son video it.

Thoughts....

Im thinking about smoking the lines. I heard PEP BOYS has a REDLINE smoker system. The only negative i have is that i can't check the leak myself. Only cost $30 dollars for an inspection.

mark kibort

if you have 0 vacuum, that's WOT. you have a leak in the test line. probably testing vacuum on the wrong source.

Want to be

Mark, is there a proper way to connect a plastic line to silcone? Everything was pretty snug. I was shocked to see the zero display on the vacuum gauge.

Is there a proper way to splice a plastic line?

SMTCapeCod

If you have a vac leak you should be running lean not rich. Unless its playing havoc with the fuel pressure regulators.

Hilton

Did you powder coat the water bridge? If so, is the temp II sensor getting a good ground signal?

Want to be

No powder coatings. I'll need to inspect the turbo gauge but I thought I had a good connection. I did notice a difference on how the engine ran when connected to the gauge. The two videos are from the same source. The front accumulator for the gas. Is there a special way to connect the plastic lines to a silcone vacuum line? I thought I heard poor vacuum caused the car to run rich. Besides a bad temp 2 and o2 sensor. I forgot to mention the temp2 was replaced just before the car died. (Needing a rebuild) Also forgot to mention I have an upgraded flow master exhaust and the heads were cleaned up by my mechanic friend.

mark kibort

you cant have a 0 manifold pressure, without the car engine not running, , or it running full throttle! if its running, you have a manifold pressure of around 20, as you showed in the first video.
as was said, if you do have a small manifold leak, it can increase idle speed. at WOT, its got to be a bad one to effect anything. ive had the lines off and leaking, and all it does is not allow for the fuel pressure regulator pressure to be regulated down a notch. (meaning, it was a little rich at idle). but at WOT, those lines don't have any measurable vacuum , so there is no real effect.
it looks like you might be tapping into the wrong vacuum source. or that line is not connected. OR, the bundle of vacuum lines at the little distributor, had one fall off.

Want to be

I have possibly found the issue.

While doing another test with the vacuum gauge properly connected (no leaks). I noticed while cold i had no vaccum.

I noticed my vaccum connection went from the fuel damper too the flappy connection. Which in turn would only function a few seconds when warm or hot.

Needless to say, i was told it did not matter where the connections went as long as everything was conneceted. Im guessing i am one connection short from the rear spider connection.

I don't have time today to see but im guess this is my DA issue.

Well, i guess it did not hurt to replace my 02 and temp2 sensors anyways...good grief.

jpc

dr bob

Interesting plumbing for sure!

The vacuum that is connected to the flappy solenoid is from the reservoir in the fender, via the check valve at the brake booster and a multitap fitting. That also connects to HVAC and cruise. Were this connected directly to manifold vacuum without the check valve and the reservoir, the heat would go on whenever you accelerate, along with defrost vents opening. The cuise control wouldn't be able to accelerate the car much either.

The fuel pressure regulator and dampers connect directly to manifold vacuum, with pressure varying with engine load. AT modulator pressure is connetc ed there too. The pressure in those lines should be low ("high vacuum") with the engine idling and/or running on a trailing throtlle. Under higher load, the manifold pressure increases to approach atmospheric pressure, same as "little or no vacuum". The variations in pressure help adjust fuel pressure, and any fuel leaking through a diaphragm gets drawn directly into the intake.


The flappy solenoid has one port that closes off when the solenoid is de-energised, while the other port is open to atmosphere. Mixing up the two connections creates a vacuum leak from the stored system, and keeps the flappy from resetting correctly. Use a Miti-Vac or similar to verify correct connection and operation.