Alfa 75 GTA 3.2 not firing

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Alfa 75 GTA 3.2 not firing

Postby Abruzzo116 on Fri Sep 27, 2024 12:50 pm

Hi Guys,

I have an alfa 75 GTA 3.2 V6 that will not start. I have injector pulse and spark to coils.

I also have crank and cam sync and fuel pressure.
Engine is freshly built.
Trigger disc is 60-2.

I have attached file with mapping if someone can take a look at it and alter any changes required.
Attachments
alfa 75 v6 24v map copy.m84-12
(72 KiB) Downloaded 62 times
Abruzzo116
 
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Re: Alfa 75 GTA 3.2 not firing

Postby David Ferguson on Sat Sep 28, 2024 2:42 am

Assuming this was starting and running prior to the rebuild -- Have you tried changing your CrIP by 360 degrees?
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Re: Alfa 75 GTA 3.2 not firing

Postby Abruzzo116 on Sun Sep 29, 2024 9:01 pm

Hi David,

This engine setup has never been started, it is the first start up.

The crip value was originally set to 445 deg by someone else not me. I have now changed the crip value to 85 and have a strong popping in the exhaust.

I have been informed to check the timing with a timing light however, number 1 coil is underneath the intake plenum. So getting to it would require remove the plenum just to check the timing with a timing light.

By chance, is there another of doing this in order to get the crip value accurate.
My client would like to see this engine run for the first time.
Abruzzo116
 
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Re: Alfa 75 GTA 3.2 not firing

Postby David Ferguson on Tue Oct 01, 2024 8:11 am

it is critical to have the CrIP correct for ignition timing, as well as fuel injection timing. If this is a new installation, it is often best to initially start with all the plugs removed (so no compression while cranking). Connect the vehicle battery to a charger / jump battery.

Connect your timing light to cylinder 1 ignition lead (adding one if the engine has Coil-On-Plug. Ground the #1 plug to the cylinder head so it can spark. You should disconnect the injectors and/or fuel pump, since you don't want to be spraying fuel while setting the CrIP initially.

Connect to the ECU with M84 ECU Manager and go to Adjust->Ignition->Crank Index Position While on this page, the timing is locked to the test advance value -- change this to 0 for this initial test. If you have a dial-back timing light, or marks on your crankshaft at specific values, you might want to use that value (especially when the engine is actually running). But for this test 0 works well.

Crank the engine, and use the timing light to look for the TDC mark. Adjust the Crank Index Position until the TDC mark/pointer are aligned while cranking. Start with your 85 deg, if the light is flashing, but you can't see a mark, change it by 15 degrees at a time (ie, 100, 110, 70. 55), until you can find the mark.

Once the Crip is set, then you can install the spark plugs, attach the fuel lines and you should now be ready to start the engine.
Good Luck!
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