Car Dies

[gabedrummin]

So I'm an idiot. I read the vacuum gauge wrong .Its reading 20cm of vacuum not inches , indicating late valve timing so I have re-check my cam timing ?

[blue62]

Originally Posted by gabedrummin

So I'm an idiot. I read the vacuum gauge wrong .Its reading 20cm of vacuum not inches , indicating late valve timing so I have re-check my cam timing ?

The scale you want to read is on the inside of the dial.
Your showing very low vacuum in the video. Looks like lees then 7 in.hg
Where is the gauge hooked into the intake at?
Also you want to use as short a hose as possible from gauge to connection to the intake.

[gabedrummin]

There is a rubber tube connecting rear flapper to left and right phelumn .Each one of these rubber tubes has a vacuum line .In my car one line goes to the fuel pressure regulator .I tee into this line between the regulator and rear connecting tube. The line is six feet long or so.

[blue62]

Originally Posted by gabedrummin

There is a rubber tube connecting rear flapper to left and right phelumn .Each one of these rubber tubes has a vacuum line .In my car one line goes to the fuel pressure regulator .I tee into this line between the regulator and rear connecting tube. The line is six feet long or so.

If I am picturing it right in my head then that should be ok.
You can double check by hooking to another spot and see if you get the same readings.
Also try a shorter hose to the gauge to see if that changes readings. Sometimes to long of a hose lowers readings.

I usually tee into the intake at the SAI connection to the intake. There is a little one way valve there that is easy to get to and remove so I can insert the tee fitting.

[Stl-986]

you dont want to be connected there. It's better to connect right by the 4 way where the check valve is on the plenum, near the AOS

[Stl-986]

The hose going to the flapper though is controlled by the change over valve.

T into the yellow ones, they are easy. The red is where you dont want to T into, that will be DME controlled with the change over valve.I think Blue & are talking the same thing with the check valve.

[blue62]

Originally Posted by Stl-986

The hose going to the flapper though is controlled by the change over valve.

T into the yellow ones, they are easy. The red is where you dont want to T into, that will be DME controlled with the change over valve.I think Blue & are talking the same thing with the check valve.

I see now (pictures help)
Yes connecting to one of the hoses you have marked in yellow is best.
Red hose with change over valve not good. Probably going to get incorrect readings.

I was watching the gauge in his video and the RPM the needle just was not acting they way I was expecting in relation to the RPM.
That is why I asked where it was connected.
So he needs to connect to another spot and run his vacuum test again.
I usually tee in ahead that one way valve in the bottom of your picture.
The small black and white one.

[blue62]

I just reread the post and it seems that he is teeing in at the hose marked in yellow on the upper left side of the picture. So he is ok there.

[Stl-986]

I think so too but pictures always help

[Stl-986]

Look for what?

Would be better to start your own thread if you are having issues.

[gabedrummin]

Yes I am connected to the line going to fuel regulator . After my heads cracked I put the motor together by one of the articles on how to install cams .It is done with the tensioners out .They get put in in later steps .I checked timing marks and every looked ok .I just read an article where I guess I should of done it differently so I am going to attempt to set the timing with the motor in the car.Any suggestion how to do it successfully ? Thank you guys.

[Stl-986]

when you did that, it is the correct process, but just checking & adjusting timing you dont need to remove them if all you are doing is adjusting timing.

[gabedrummin]

I removed the injector from cylinder 4 and checked it against a new factory injector and it ohm's out the same, connected it to a battery momentarily and I can feel it opening and closing . Next I will check timing but its looking like a valve problem.

[gabedrummin]

Miss-fire gone .I went to reconnect injector and said to myself check the colors of the wire going to the injectors and low an behold I had connector 4 and 5 on the wrong injector .Durametric showing no misfires .Roughness indicator is flat lined ...So it looks like I'm to blame for this problem .What I don't understand is why was the software only showing one cylinder misfiring? So I'm going to put the car back together and se if it dis when coming to a stop. So The scenario is accelerate rapidly stop rapidly idle drops below normal and car dies ?

[blue62]

Originally Posted by gabedrummin

Miss-fire gone .I went to reconnect injector and said to myself check the colors of the wire going to the injectors and low an behold I had connector 4 and 5 on the wrong injector .Durametric showing no misfires .Roughness indicator is flat lined ...So it looks like I'm to blame for this problem .What I don't understand is why was the software only showing one cylinder misfiring? So I'm going to put the car back together and se if it dis when coming to a stop. So The scenario is accelerate rapidly stop rapidly idle drops below normal and car dies ?

Some OBDII systems will shut fuel injectors off under certain misfire conditions.
The feature is designed to protect the Catalytic converter.
So then they do not show misfires for that cyl.
I do not know if Porsche of the early era's like ours does this or not.
Doubtful but possible.
Info on the more advanced workings of the Porsche ECU's is very limited

Crossed injector wires would explain the backfire through the intake.
I bet if you do a "PROPER" LOL vacuum test now your numbers will be improved.

[gabedrummin]

The wire harness was not stretched the wires going to 4 were the longer ones or so I thought . So 2 points to who ever asked if the wiring was right . I am happy to inform everyone the backfiring is gone . I assume it was firing fuel as the exhaust was opening . I don't know . Motor is running much better punching the accelerator from an idle car rapidly accelerates with no bogging or pooping seems like it's running right . Tomorrow I will button it up and go for a test ride.Thank you to everyone for all the help and guidance .Thank you all. Thank you.

[Stl-986]

Interesting. How could you have done that though? The wires are pretty much set to the length, unless they were really stretched