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-   -   1982 SC with EFI ITB doesn`t start (http://forums.pelicanparts.com/porsche-911-technical-forum/955752-1982-sc-efi-itb-doesn-t-start.html)

Cheshire Cat 05-06-2017 04:06 AM

1982 SC with EFI ITB doesn`t start
 
Well, it is time to ask proper community for an advice I reckon.
Long story short - 1982 SC with Triumph 675r throttle bodies and EFI. Quite common things this days so nothing really spectacular here.
The problem is - she doesn`t start.
Working with this:
EMS EM-80 ECU (Ozzie company)
AEM EPM for the signals
COP
Main load - TPS
Wanna go sequential injection with wasted spark. But for now batched fire will do.
Firing order set to ignition ch.1 for 1-4 cyl, ign. ch. 2 for 3-6 cyl, ch. 3 for 2-5
Timing light shows TDC withing 5 degrees. All the plugs give fire.
But she still doesn`t start.
Gentlemen, let me know what you think cos I`m ran out of ideas. I`m frustrated.
https://www.youtube.com/watch?v=kdhvlmJOcMM

JJ 911SC 05-06-2017 04:24 AM

If the plug are firing, you are probably missing the fuel.

Cheshire Cat 05-06-2017 04:48 AM

Quote:

Originally Posted by JJ 911SC (Post 9577697)
If the plug are firing, you are probably missing the fuel.

Tried on some point to open a throttle, ended up with a flames from the intake. So, fuel is there.

al lkosmal 05-06-2017 06:57 AM

I am somewhat experience with EFI systems, but not familiar with the EM-80. However, if i can review your datalog file, I may be able to help. What software program are you using for data-logging? If you have a datalog file and i can download the logging software, i will review your log file and see if i can spot the problem.
regards,
al
PS: It's weird, but it appears that your throttle bodies are moving/jumping every time there is a backfire through the intake...like they are loose and not bolted down. If so...that would be a massive vacuum leak.

JJ 911SC 05-06-2017 07:38 AM

Quote:

Originally Posted by al lkosmal (Post 9577835)
... PS: It's weird, but it appears that your throttle bodies are moving/jumping every time there is a backfire through the intake...like they are loose and not bolted down. If so...that would be a massive vacuum leak.

I was not sure if I was seeing things... That would not help for sure.

kjchristopher 05-06-2017 08:11 AM

Resembles timing being 180 degrees off.

kjchristopher 05-06-2017 08:13 AM

Quote:

Originally Posted by al lkosmal (Post 9577835)
PS: It's weird, but it appears that your throttle bodies are moving/jumping every time there is a backfire through the intake...like they are loose and not bolted down. If so...that would be a massive vacuum leak.

Almost like they are attached with rubber bases that bolt to the intake.

al lkosmal 05-06-2017 09:03 AM

Quote:

Originally Posted by kjchristopher (Post 9577901)
resembles timing being 180 degrees off.

+1

JJ 911SC 05-06-2017 09:58 AM

Quote:

Originally Posted by kjchristopher (Post 9577901)
Resembles timing being 180 degrees off.

Australian ECUs

JJ 911SC 05-06-2017 10:31 AM

Quote:

Originally Posted by Cheshire Cat (Post 9577690)
... Firing order set to ignition ch.1 for 1-4 cyl, ign. ch. 2 for 3-6 cyl, ch. 3 for 2-5...

While this is correct (Direct Fire Unit to Spark plugs wiring), your ECU like mine (Electromotive) probably trigger the injectors sequentially 1, 2, 3, 4, 5 and 6. Thus only 1 and 4 are direct match (wiring from ECU drivers to injectors), the others need to be workout.

Is this a new installation?

Do you have a schematic of your set up?

gomezoneill 05-06-2017 10:35 AM

Definitely a timing issue. Send Al your logs he'll figure it out.

Cheshire Cat 05-06-2017 01:46 PM

Quote:

Originally Posted by al lkosmal (Post 9577835)
I am somewhat experience with EFI systems, but not familiar with the EM-80. However, if i can review your datalog file, I may be able to help. What software program are you using for data-logging? If you have a datalog file and i can download the logging software, i will review your log file and see if i can spot the problem.
regards,
al
PS: It's weird, but it appears that your throttle bodies are moving/jumping every time there is a backfire through the intake...like they are loose and not bolted down. If so...that would be a massive vacuum leak.

Thanx Al for the input. I was hoping for you to help since basically you're posts I was reading a lot.
Anyway, tb's are bolted on a rubbber adapters and they are a bit flexible. But I will tighten the bolts for sure.
Vaccuum leaks do exist through the tbs vacuum nipples I don't use. But on this stage I reckon it doesn't matter. The goal is to start her and fix the rest knowing she's alright.
I will try to figure out how to use a logger. Have to check memory card in theECU might happen there ar plenty if logs.
Btw, I have tried to move the ignition to 180 degrees and seemd like the engine struggled a bit less.

Cheshire Cat 05-06-2017 01:49 PM

Quote:

Originally Posted by JJ 911SC (Post 9578027)
While this is correct (Direct Fire Unit to Spark plugs wiring), your ECU like mine (Electromotive) probably trigger the injectors sequentially 1, 2, 3, 4, 5 and 6. Thus only 1 and 4 are direct match (wiring from ECU drivers to injectors), the others need to be workout.

Is this a new installation?

Do you have a schematic of your set up?

Yes it's a new one. I wired the injectors with the original sequence ea. 1-6-2-4-3-5. Not sure if I have to leave them like that though.
And again, this is not vital for wasted spark I believe.

Cheshire Cat 05-08-2017 10:12 PM

Thanx guys for giving an idea of what to do with the timing. You kjchristopher and Al were right. She was almost 180 degrees off. Fixed that and all the vacuum leakis through the vacuum valves and she has started.
And the 6-th cylinder tb a bit loose on the adapter, will make it tight.
https://www.youtube.com/watch?v=oia3v7hQm6o
if you`re interested :)
The happiest day of a year so far :)))

JJ 911SC 05-09-2017 01:42 AM

Great, on to the next project...

al lkosmal 05-09-2017 07:50 AM

sounds like it is actually running pretty good. Now, as you proceed to fine tune.....datalog and review....make changes..one at a time...datalog and review...make changes...one at a time....datalog and review.....I think you see where this is going...........

regards,
al


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