Just replaced the Spider Injector, Fuel pump, and fuel filter on 2000 Blazer 4x4
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From: Belleville, Michigan
Yup, all 94 "W" engines are CPI, (also referred to as CMFI, central multiport fuel injection) and look like this:
1996 through 2002 "W" are CSFI, and look like this:
2003 through 2005 are VIN "X" and look very similar, but they do not have an EGR valve.
1996 through 2002 "W" are CSFI, and look like this:
2003 through 2005 are VIN "X" and look very similar, but they do not have an EGR valve.
Moderator
Joined: Mar 2009
Posts: 8,453
From: Belleville, Michigan
That is correct. See post #24.
Your 94 has one injector, (2 wires) and it is batch fired, (fires whenever ANY cylinder calls for fuel). The injector fires 6 times for each two crankshaft revolutions. 1996 and newer has six injectors, (12 wires) and each injector fires sequentially with the firing order. Each injector fires one time for each two crankshaft revolutions.
To upgrade your system, it would require a 1996 or newer engine, PCM, fuel pump, engine wire harness, etc, etc, etc, ton of work.
Your 94 has one injector, (2 wires) and it is batch fired, (fires whenever ANY cylinder calls for fuel). The injector fires 6 times for each two crankshaft revolutions. 1996 and newer has six injectors, (12 wires) and each injector fires sequentially with the firing order. Each injector fires one time for each two crankshaft revolutions.
To upgrade your system, it would require a 1996 or newer engine, PCM, fuel pump, engine wire harness, etc, etc, etc, ton of work.
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Joined: Aug 2014
Posts: 48
1995 and older VIN "W" are CPI, (Central Port Injection). There is one fuel injector, and a poppet valve at each intake port. There is no upgrade for this system. The video is 1996 or newer which is CSFI, (Central Sequential Fuel Injection) also VIN "W". There are 6 fuel injectors in the metering block, with poppet valves at each of the intake ports. The upgrade to MPI, (Multi Port Injection) can be done on 1996 through 2002. It relocates the injectors to the intake ports and eliminates the poppet valves. 2003 through 2005 S&T body 4.3L originally came with MPI and the 8th character in the VIN is "X".
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Posts: 8,453
From: Belleville, Michigan
Mickey, S&T designate the body platform of the vehicle, (Blazer, Jimmy, Bravada, & pick up). "S" = 2 wheel drive, and "T" = 4 wheel drive.
In 1983 when the first generation S&T platforms were introduced, the full size version of Blazer & Jimmy, (C&K) were also in production. ("C" = 2 wheel drive, K=4 wheel drive). Obviously creating confusion having two platforms of Blazers & Jimmies, in 1996 GM renamed the C&K platform to Tahoe & Yukon. The numbers after the platform indicate the load carrying capacity of the vehicle such as S10, S15 etc.
In 1983 when the first generation S&T platforms were introduced, the full size version of Blazer & Jimmy, (C&K) were also in production. ("C" = 2 wheel drive, K=4 wheel drive). Obviously creating confusion having two platforms of Blazers & Jimmies, in 1996 GM renamed the C&K platform to Tahoe & Yukon. The numbers after the platform indicate the load carrying capacity of the vehicle such as S10, S15 etc.
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Joined: Aug 2014
Posts: 48
I did it, pretty easy upgrade! Went with a junk yard 2004 model and cleaned it up a bit. This actually feels smoother than the old version. Plus, I must have been losing fuel since I seem to be getting better mileage. Thanks!