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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: the_legend_1981 on July 30, 2012, 03:48:31 pm

Title: 90 motor in 87 problems
Post by: the_legend_1981 on July 30, 2012, 03:48:31 pm

My friend is putting a motor out of a 90 chevy in his 87(replacing 4.3 tbi). He is not getting the fuel pump or injectors to work. It fires when given some gas straight to throttle body. Is this an ecm issue? Any help is appreciated

Title: Re: 90 motor in 87 problems
Post by: Blazin on July 30, 2012, 10:07:40 pm

Did the 90 motor run in the 90 truck?
Is he trying to use the 4.3 ECM?

Title: Re: 90 motor in 87 problems
Post by: the_legend_1981 on July 31, 2012, 08:42:53 am

Yes it ran and he is using the 4.3 ecm

Title: Re: 90 motor in 87 problems
Post by: slammed79 on July 31, 2012, 10:28:18 am

He needs the ecm from the 90, assuming its a v8. A 6cyl ecm isn't going to power a V8

Title: Re: 90 motor in 87 problems
Post by: Captkaos on August 01, 2012, 09:10:15 pm

First is the fuel pump priming with the key on?  Do you have fuel pressure?  When turning over can you see the injectors spraying?  BTW the ECM chip and the injectors are not the same on a 4.3L vs 350...