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.

[blue62]

Originally Posted by 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.

Good to hear you got it sorted out.
The backfire into the intake was happening because it was firing with the intake valve open or partially open.
I tried to list all the ways that can it happen in post #24.
missed fuel timing
As happens most times it was something so simple it was overlooked.
Let us know how the test drive goes if you have time.

[gabedrummin]

Test drive went great car revs out .Got on the free way opened her up got the motor up to operating temp pulled off came to a stop and the rpm's are not dipping below normal and the best part the cars not stalling out when I stop ..Yea .It is amazing how something so simple can cause you to pull your hair out .Thank you all . I called the Dealer . I should not mention their name but they refuse to refund any money .PORSCHE OF NORTH HOUSTON .Are not very good mechanics . I told them That I took the motor out I put it back .They said they needed 3 hrs. To go over all the obvious stuff . Only 140 an hour because its a classic . Recommends replacing the mass air flow after I told them I tried both that I have and it made no difference Total for the bill was 904.00 I did ask to have the clutch slave bleed while it was there 120.00 I am not very happy with the dealer .All their expertise tools, software and they could not figure it out . They should be extremely embarrassed at the low level of customer service and on top of that wanted 2200.00 more to fix it .The first time I had my car at Porsche of North Houston they ripped my top and tried to say it was like that .I should of known to never go back to shop but I took a chance because I was desperate . I am a toolmaker /Designer not an auto mechanic . I know way too much about this 986 .L.O.L. Thank you all for pointing me on a path to success . Thank you all. What did you do with your Boxster today fixed it again .

[blue62]

Originally Posted by gabedrummin

Test drive went great car revs out .Got on the free way opened her up got the motor up to operating temp pulled off came to a stop and the rpm's are not dipping below normal and the best part the cars not stalling out when I stop ..Yea .It is amazing how something so simple can cause you to pull your hair out .Thank you all . I called the Dealer . I should not mention their name but they refuse to refund any money .PORSCHE OF NORTH HOUSTON .Are not very good mechanics . I told them That I took the motor out I put it back .They said they needed 3 hrs. To go over all the obvious stuff . Only 140 an hour because its a classic . Recommends replacing the mass air flow after I told them I tried both that I have and it made no difference Total for the bill was 904.00 I did ask to have the clutch slave bleed while it was there 120.00 I am not very happy with the dealer .All their expertise tools, software and they could not figure it out . They should be extremely embarrassed at the low level of customer service and on top of that wanted 2200.00 more to fix it .The first time I had my car at Porsche of North Houston they ripped my top and tried to say it was like that .I should of known to never go back to shop but I took a chance because I was desperate . I am a toolmaker /Designer not an auto mechanic . I know way too much about this 986 .L.O.L. Thank you all for pointing me on a path to success . Thank you all. What did you do with your Boxster today fixed it again .

You could do a report to the Better Business Bureau.
At least that would be on record.
In the end its running right.
Have fun with it.
Touch base now and then here on the forum