MPFI fuel injection replacement

POSSUM454

MEMBER
1996 GMC SIERRA
5.0L
V8
2WD
MANUAL
130,000 MILES

Can't get the injectors to lock in place even after thorough cleaning of the ports. Are they not supposed to lock in place? Seems like the jacket on the fuel nozzle is too big to fit in the port. Did not remove the plastic jacket around the injector. Help please?

Sunday, July 12th, 2020 AT 8:34 PM

4 Replies

DANNY L

MECHANIC
5,648 POSTS

Hello, I'm Danny.

Just to get a better idea are you not able to lock the fuel injector connection on the top? Or, did you remove the upper intake manifold to access the lower intake manifold to work on the spider injectors?I've attached both pictures and circled in red. Let me know and we'll go from there. Hope this helps and thanks for using 2carPros.

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Sunday, July 12th, 2020 AT 9:23 PM

POSSUM454

MEMBER
3 POSTS

I just removed the upper plenum, not the lower intake. I just can't get the new MPFI injector to lock. It looks to me like the plastic jacket is too big to fit in the hole on the intake. Now I'm not talking about the whole injection system itself locking onto the bracket just each injector themselves.

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Sunday, July 12th, 2020 AT 11:24 PM

POSSUM454

MEMBER
3 POSTS

In the picture, I am not having a problem with the wiring harness, the injectors themselves are the problem. I replaced the old CPFI with the new MPFI system.

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Sunday, July 12th, 2020 AT 11:29 PM

DANNY L

MECHANIC
5,648 POSTS

Hello again.

Can you take a picture of an injector end with your cell phone and upload here so I can see the end you're speaking of? I like the 1988-1998 obs trucks I've owned 2 myself. Hope this helps and thanks again for using 2CarPros.

Danny-

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