Introduction: 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.
Step 1: Take a Look at the Injector and Get You Stuff Together
At this point you have pulled the injectors from the fuel meter body, you have your injector reseal kit with all of the o-rings napa and everyone else has them .
napa's part is....
Fuel Injector O-Ring Kit
Part Number: BK 735359
Make sure the meter body has no cracks, this can be fixed in a pinch, Google plastic welding with soldering iron.
Make sure the black plastic tubing is not cracked or too brittle to be reinstalled. They need to be able to hold 60lbs of fuel pressure. If in doubt take an old piece of tubing to the local auto parts store and get some double walled plastic gas line tubing. Ford uses quite a bit of it, as does BMW.
You will need the following in addition to your o-ring kit
1. Carb Cleaner
2.Sea Foam in a can "Deep Creep"
3. A Pot O Boil'in Water and or a Heat Gun "Heat gun is faster but water is safer"
4. A Few pairs of needle nose pliers
5. An air compressor with blow gun.
Optional but highly recommended is an ultra sonic jewelry cleaner "got mine for $30.00 from harbor freight, for the wife......."
Step 2: Heat the Tubing and Pull the Poppet Out.
With this step be patient, you need too heat the black tubing right at the poppet to just the right temp. the safest way to do it is to dip the last inch or two in a pot of boiling water for about a minute.
As soon as you pull the poppet out of the water start to work it out of the tubing with two pairs of pliers.
Be very careful not to scratch the poppet or break the hose. Don't squeeze to hard on the poppet or you will crush it an then you might as well buy the MFI kit cuz the cost about $80.00 a piece.
You will only have a few second at a time to work the poppet out before it needs to go back in the pot. Be gentle and it will come out.
If you are using a heat gun it only takes a few seconds to work it out, but if you over heat the tubing it will become brittle and increase the chance of making your problem much worse.
Step 3: You Got It Out! Time to Clean It.
Great you got that tiny little thing out!
Don't lose it!!!!
Now it is time to test/ clean it.
You might have a better way to do this but the poppet fits perfectly in hole of the rubber piece of my air compressors blow gun.
The poppet is designed to open at about 40lbs of pressure. So l like to start there.
1. Set your regulator to 45lbs.
2.Insert poppet into blow gun nozzle, or ring up some rubber tubing and clamps to hold firmly. The last thing you want is for the poppet to be shot across the garage never to be seen again.
3. Give it a 45lb shot of air. if the poppet opens then obviously it is fairly clean. most likely nothing is going to happen.
4. Take the blowgun from its quick connect and fill it with carb cleaner.
5. Give it another shot of air, if nothing crank it up to 60lbs. and try again.
6. When it finally gives way repeat the procedure until you are satisfied that it is clean.
7. Switch to the deep creep and repeat a few more times."the deep creep will remove varnish an keep everything from flash rusting."
Step 4: Put It Back Together
Now all thats left is getting the poppet back on the hose.
1. Heat the hose like you did before. Heating only the very end will help you keep from kinking.
2. Slowly press the poppet back in, don't rush it.
3. let it fully cool and give it a few good tugs to make sure it set.
The O-ring set comes with instructions follow them.
Make sure you don't have any leaks before you seal up the upper intake manifold!!!
Drive around for 50 or 60 thousand miles and repeat the process and save some hard earned cash.
55 Comments
Question 11 months ago
I have a 96 k1500 5.7 vortec I replaced the spider the truck runs but I have gas coming out from the spider itself..
Question 4 years ago
I have a 96 Chevy 5.0 cranks but won't start. I don't have any fuel pressure on the fuel rail. I've replaced the spider, coil, ignition module, fuel pump, fuel pump relay, crank sensor, plugs. If I take the core out of the fuel rail where you hook up the pressure tester at it will shoot fuel out, put it back in and still no fuel pressure. Any help would be greatly appreciated.
Answer 1 year ago
96 Chevy truck replaced fuel pump twice and fuel lines, and only started when I put gas in the carborator what could it be
Answer 3 years ago
Hmm ok gee no fuel pressure wow well you must start your testing first at the pump jump a wire at the + terminal of pump to + terminal of battery hmm do you hear the pump running?? Now check for fuel at rail.
Question 1 year ago on Introduction
We replaced the spider on my 2007 gmc pickup and gas is shooting out the spider.
Question 1 year ago
I'm working on my 2000 Chevy Express 2500 4.3 took out the spider injector and pop its took puppets off of hoses and clips try to clean put all back together starts and idles fine but once I get to drive and give it some gas and misfires took it all back apart realized that the puppets have numbers on it one number one two has number two two has number three and one has number four so I'm wondering if they have an order or a certain cylinder number they go to I know there's numbers on the side of the spider injector so do the poppets go to a certain cylinder
Question 2 years ago on Step 1
Ok i have a 94 Jimmy 4.3 cpi and i have a small pin hole in the plastic line that runs from the spider to the intake where the popit is the back two lines were supposed to go over the main fuel lines but when they replaced the spider the put it under the main fuel lines and now they both have one little pinhole any ideas of what i can do and anyone know what size the small black tubing size?
3 years ago
I just want to sayi have a 96 tahoe4x4 136000 miles every thing was great about it til the tune up. now i have sent the last yr half. trying to get it running again every sensor relace comuter replace so put new udated spidder injectors in well some how instead of starting back fired blew vale cover off on drivers side .blew the hole front of timiming chain cover off . now here i go again . whats the deal with these 5.7 vortex that after a tune up they never want to start again
Question 5 years ago on Introduction
Hi so I had some guy working on my 99 Tahoe 5.7 vortech Tahoe and it seemed he was making it worse. Cause it still wasn't turning on. Well it all started from replacing fuel pump. I replaced the fuel filter then fuel fuse relay, ignition coil distrubitor rotor spark plugs and Tahoe turns on but only for about 2 seconds then off. Then after him checking the fuel pressure, it catches fire and I quickly got it out. Now I'm here trying to work on it myself. Unsure what he did wrong to it cause I've noticed some screws missing ect. Can u tell me what u see plz
Answer 3 years ago
Hi with the Chevy Vortec a lot of them had a security pass lock. Starts shuts off. So to fix will take about 35 minutes. Get inside the vehicle. Turn key on. Don’t touch anything and I mean anything. Window radio nothing. It had to be undesturbed while doing this. After 10 full minutes turn off and back on for 10 minutes. Once you’ve finished the third turn off and try to start.
Answer 4 years ago
In our shop yesterday we had a '99 suburban with the same result as yours after several test we replaced the fuel pressure regulator for about $45 from Orileys it is clamped to the end of the spider housing, that cured the problem this system is very sensitive to pressure being to low, it needs at least 46 psi at the rail to even start to operate. It also has a history of failing due to varnish buildup, I would use Marvel Mistry in the fuel tank at least once a month to keep it clean. If you remove the fuel filter under the vehicle and dead head the fuel pump you will need at least 70 to 80 psi if not consider a possible pump problem. best of luck..Mark
Question 3 years ago
I was working on my chevrolet silverado 2007 classic body 4.3 try to swap the spider injectors, everything go fine until the popets on cylinder 5 and 6 get stock and inside the rest of them came out easily but this two cant come out, how to take it out . please need ideas.
4 years ago on Step 1
Hi, I'm attempting this job. Can you tell me how to get the injectors out of the fuel metering body, and how to get those pinch clips off of the poppet ends? Thanks
4 years ago on Step 4
Thankyou
4 years ago
I replaced to injection system it was a pain getting it to set in place but it’s up and running. That was about a year ago. Yesterday it just stopped I popped the hood and noticed the top cap on the module has leftover because the little snaps are broken I pulled the whole module back in place with vice grip and put the cap back on it cranked right up. Now my problem is what can I do to hold the cap down in place. Maybe drill a very small hole and screw from the sides?
4 years ago
I went with option 6."junk the 4.3 Vortec and install the carbureted 327ci ""5.3 for you kids"" you pulled from a 67 Chevelle" on my 1995 4X4 Blazer. Just picked up a 96 Jimmy that is very clean,rust free and fresh paint, plan was to swap the 327 into it because the blazer rusted away, but I think I will try option 5 first.
6 years ago
I have a 96 tahoe 5.7 vortec an So far after trouble shooting, i have changed distributor cap, fuel pump, fuel filter,oil, oil filter, spider injector an set timing, after all that its knocking can one one please help im up into the thousands an need my truck fixed or i will lose everything. Thanks lisa
Reply 4 years ago
HI Lisa, the first thing I would do is check the impulses from the computer to the injectors this can be done with a test noid light, do not use a test light or ground any of the computer circuits, wire the noid light (5v) in place of the injector and then turn over the engine to see it it flashes. if it flashes that means that the computer is working properly no failure there. The timing of this unit is set by the computer itself but the synchronizing of the cam sensor and crank sensor must be within 2 degrees adjusted by turning the dist....best of luck..Mark...
Question 5 years ago
I did a timing chain ..oil pump...and new lifters..on a99 surburban v8 vortect..and cleaned everything that came off the engine including the plenum and I'm very (O C D) and now I'm getting Cyc 6miss fire could I have caused the injector feed line to have come off of possibly caused it to clog up with contaminant
Question 5 years ago on Introduction
Do you have to take the plenum of the moter to do this task and I'm working on a 99 vortect !