Poor Mans Repair Guide For Chevy,GMC Vortec Fuel Injector spider or CSFI System

Picture of Poor Mans Repair Guide For Chevy,GMC Vortec Fuel Injector spider or CSFI System
I hope I can take some of the Dark Voodoo power away from the notorious Vortec injection spider. If your reading this then  like I did you have been searching  the web and under the hood of you GMC Jimmy, S10, Astrovan, Or Chevy Blazer trying to figure out what to do about that crazy injection system in your truck. Well you have a few choices
1. Buy a new spider set for a small fortune.
2. Buy a "MPFI" retrofit system for about $300.00
3. Try Replacing individual injectors or "poppets" 
4. Junk the p.o.s. the front end is falling apart anyway.

or you can

5. Spend about $16.00-30.00 and a few hours of your time and fix it like I do.

This guide explains how to clean/repair  leaky or stuck poppet valves/injectors. only continue if you are sure that your injectors are getting a signal from the ecu and are actuating. if your not sure, Google it, do your testing and come back.

I am not responsible for any kind of damage or injury you may cause yourself or your car.  Messing around with a fuel system is dangerous, gasoline leaks can and will cause fire and or explosion. Be Safe, Be Smart, Or be Dead.
Dave855 months ago

I had a problem with injector 8 showing as a p0308 misfire. So l replaced everything plugs, wires, distr cap, rotar, ignition coil, and the problem still remained. I took mine to a dealership because I wanted to be absolutely sure it was the injection. After a quote of 1300 bucks, I decided that I could do the job myself. From the pics below, you can see that the fuel leaked into my intake and was burned leaving a residue. I highly recommend an MFI upgrade as I've noticed an increase in the MPG and HP. I did the replacement following a youtube video and I wanted to give back to the web community. Thanks.

Royevatom2 years ago
There is a semi clear tube liner at least at each end of the tubing. Under heat it collapses when the fitting end at the meter is reinstalled or at the poppet end when the poppet is forced into the tube after being heated. Once this is done you have have had it. It can not be reassembled. Two units down now after removing the fittings from the tubing.
Until there is more information and an address for the issues I ran into I would advise anyone to avoid this means of repair.
Royevatom2 years ago
Back again, it appears that the cap on the inlet end of the poppet did not come out as it seems to be melted in place.
The engine overheated (plastic heater control valve came apart at weld) after R&R the heads 5,6,7,8, not hitting. I replaced the unit from a yard now 1,5, 7, not hitting.
So either they are clogged or came from an engine that also had overheated.
I would go back to the throttle body in a minute except it is way expensive.
Plastic and engineers have become good friends and left us out in the cold or heat I should say.
Royevatom2 years ago
Boiling water is not hot enough. It is not reliable enough temp wise.
If you soften the tubing in one way or another enough to get the poppet out there is a cap on the inlet end if this does not come out with the poppet it will be destroyed when you reinsert the poppet. It is easily crushed. Trying to determine which tube the poppet came out of with out the cap is impossible as there is more line resister still in the tube.
Removing the poppet is easy reinserting it requires a temperature close to the melting point of the tubing once past it there is no return.
I have not tried removing the tubing from the metering unit and then blowing thru it to check for function and cleaning.
Better have several units on hand before you try this.
rolavez2 years ago
Can I vary the pressure thru the adjustment screw of the regulator ?
gtoner503 years ago
Damned if I can get these things back together. Who carries the tube? All the stores I go to have no idea what it is. I can't even find it on line. Now I have to go to the yard and dig up another unit.
elgray033 years ago
Sooooooo happy I found this. My truck has been having fuel problems concerning starting and I thought it was the fuel pump (which needed to be replace anyways), but I found out I have a leak in my injectors. I recently replaced the spider cylinder in my truck because my old one was clogged. The one I replaced it with was used from another engine I have. Now the one I put in my truck has a leak. Would it be easier to fix the leak or the clogged injector?
krhagerich (author)  elgray033 years ago
It depends on where it is leaking. If you have 2 spiders mix and mach parts till you have a good one.
I love this and I did this and it worked, but cylinder #3 still miss fires. Then I bought the after market MPI Set-up. Also Plugs, wires, rotor and cap. Pulled he distributor, cleaned and lubricated it, then had to rebuild it because it was WAY to sloppy! The timing mark danced all over the place, now it is nice and steady. It DID have 96,000 miles on it! BUT, guess what, #3 Cylinder still miss fires. Now I am going to the Dealer too have the wire harness between the Spider and the ECM replaced! If that doesn't fix it then I plan to build a new motor, built correctly, and that will include a custom manifold with real individual injectors. #3 has to stop miss firing, I don't like it!
krhagerich (author)  pddonovan20113 years ago
First check your plug on cyl 3 it is very, very common for this spark plug to cross thread because it is so hard to get to. Next check your compression..If its good you don't need a rebuild. If you have good compression it will come down to a vacuum leak because of bad lower intake manifold gasket..also a big problem with theses engines or depending on what year you have it could be a leaky fuel line "if it enters the manifold from the back of the engine" or leaky fuel pressure regulator. To check this pull the top intake manifold off peek at the lower manifold and if you have any leaks you will see a clean spot where the gas is washing the manifold. Check your fuel pressure as well to see if it is dropping pressure.
They make an aftermarket spider with mini injectors that works great for about $250.00. I have installed full sized injectors in these trucks in the past and to be honest its not worth it.
im2scary3 years ago
THANK YOU! I was going to tear mine apart and try to clean it, as I have over 200,000 miles on my engine and don't want to dump over $300 into right now. This is going to help out tremendously. I'll let you know if it works for me.

Thanks again for sharing this!
Gathrax4 years ago
Gm says to clean em' with some specialized equipment and everyone else says to convert to the MPFI unit. Most people assume your willing to dump $300 into 14 year old truck with 200k on it. Great job on giving some info on a question everyone else seems to disregard.
krhagerich (author)  Gathrax4 years ago
No prob...I'm glad someone actually saw this. Its my first write up. I just did a diy transmission rebuild on this truck. I was told by everyone that I would need about $1000.00 worth of tools. I made all of the tools with scrap metal and some brain juice. running great so good in fact that the transmission shop that told me it could not be done wants to outsource some work to me.
krhagerich (author) 4 years ago
Sorry about the poor pics, I will do a video next time I do this.