CSFI to MPFI conversion identification

[HankHill]

Hi -

Is there an easy & positive visual inspection method to determine which injection system is currently installed? I don't have maintenance records from the previous owner, so I don't know which system is in my '00 Tahoe.

I tried to search, but didn't have any luck.....

HH

[gpracer1]

The only way I could think of is to open the throttle body butteryfly (or remove the TB) and shine a flashlight in there. If the 8 fuel lines go into the manifold with two little rounded clips sticking out, then that is the old style. The new style will just be the line/injector going into the manifold with nothing else visible since it does not have the external clips.

You might need a mirror to get in there and see it.

[SunlitComet]

take off your injector harness and look down in the connector pit which picture looks like yours? See the difference in the holes above each line? One dot the other t-shaped?

[sparg93]

what year did they start with the new style? what is the benefit?

[SunlitComet]

it was started around 2003 I believe. At least that is when GM started sending out letters to owners. Injector is taken out of body and new type is installed downsteam of each line. No more poppet junk. Cleaner burning fuel, smoother idle, and what not. Comes with new regulator installed.


OLD
http://www.fiveomotorsport.com/catalogues/92/833-22102-cpi_unit_600.jpg


NEW

http://ecx.images-amazon.com/images/I/41XsruwHlrL._SS400_.jpg


Got MPFI?

[sparg93]

Interesting...my rig runs really smooth, but i know i have a slight spider leak on both banks...i avg ~15.5mpg.

Worth the upgrade?

[SunlitComet]

oh and new is only about $250 at amazon for a Delphi unit.

---------- Post added at 06:02 PM ---------- Previous post was at 06:02 PM ----------

Yes.

---------- Post added at 06:03 PM ---------- Previous post was at 06:02 PM ----------

http://www.amazon.com/Delphi-FJ10566-Fuel-Injector/dp/B000TYLIFS/

[sparg93]

i hate to ask this...but for $250, what do you think the benefit is for me? (assuming the above extra intel i provided)


My truck runs really smooth and my mileage is decent for 4dr 4x4 with 1.75" lift & 33" tires.

[SunlitComet]

I guarantee it will have to be done eventually so do it before it suddenly decided to start acting up. And no spider leaks. so if you leak now you will probably get some performance and mileage back.

[sparg93]

I have a BB tune and recently lowered the thermostat...should i sent the computer out to be adjusted if i also do this upgrade?

you're right...i also need to replace the intake manifold gasket and while everything is off, i might as well do this too.

---------- Post added at 09:29 PM ---------- Previous post was at 09:16 PM ----------

any idea the difference between the AC Delco & Delphi Unit?
http://www.amazon.com/ACDelco-217-3029-Fuel-Injector/dp/B000NW8EU8/ref=au_pf_pfg_s?ie=UTF8&Model=Tahoe%7C499&n=15684181&s=automotive&Make=Chevrolet%7C47&Year=1999%7C1999&newCar=1&carId=002

[gregsb]

Delphi makes the AC Delco unit so it is the same, you just eliminate the middle man.

I will be doing this swap next spring. The previous owner of my truck had the intake gasket done and the recommended initial service done on the injectors before I bought it, it sucks that he did not want to spring for the spider replacement as it was too expensive through the dealer.

[SunlitComet]

Sparg, If you had a scan based tune AND really noticable issue with the spider when it was tuned, they you MAY want to have the scan tune fine tuned. I probably would not bother with it, Especially if it the tune was question based..

Now the acdelco is a re-branded Delphi unit however that delco unit has the plenum, extra spider body gasket and TB gasket which technically can reuse. But since you want to do the intake gaskets I recommend the (http://www.amazon.com/Fel-Pro-MS90131-Manifold-Gasket-Set/dp/B000C2GE4C/)Fel-Pro MS90131 Manifold Gasket Set (http://www.amazon.com/Fel-Pro-MS90131-Manifold-Gasket-Set/dp/B000C2GE4C/). It has the lower gasket plenum, TB, Dizzy, RTV seals. You can discard or save the extra spider body fuel line o-rings and spider body oval seal. They are in the Delphi unit already and fuel o-rings are already in place. New manifold bolt are highly recommended and are Fel-Pro ES72224 Engine Intake Manifold Bolt Set (http://www.amazon.com/Fel-Pro-ES72224-Engine-Intake-Manifold/dp/B0039SOMUE/). So with the delphi unit, felpro gasket set and new bolts at current amazon pricing you can get all that for less then just geting the delco unit. You can't go wrong. I would recommend while you have it apart you have give the manifold and plenum a good cleaning. Order up while the pricing is good.