I have a 2000 LT 4x4 4.3 with 105K blazer. I would like to know where I can go on this site on changing the spider injectors out.

I have a starting problem once the blazer has sit for over a day. I have look at the fuse and relay both are good there. The fuel pump in the gas tank appears to be working fine.
I have no fuel pressue reguator problems (no hestation or any other signs of that). So that leaves me the spider injectors. I was replacing one of the bumpers that go between the frame and the body last week and when I had the tire off on the pass side the smell of gas was very strong, again leading the injectors. If this goes uncheck am I looking for a engine fire? Once the blazer is started, takes about a mintue with turing the ignition off and on waiting for pressure to build it will run fine all day long, no problems what so ever and will start just fine. Let it sit for a day or two and I have start it like an old fashion carb job. I am more concern about a engine fire then anything.
So if someone can point me in the right direction for changing out the injectors, it sure would be appricated..

Thanks
Dennis

 

First: you're in the wrong forum. This is for DIY article submissions.

Second: you seem to have cruised around a bit. There is no substitute for the proper Fuel Pressure diagnosis.
Your prime cycle routine suggests PERHAPS leaky injectors but I dont see how gas smell in passenger wheel well gets you there. The injectors are inside the engine. What about when you open the oil filler? Throttle body cap?
Driveability does NOT rule out the fuel pressure regulator.

In the DIY forum there will be an articles covering this. If not, somewhere on here.

To find that.. do a search in DIY . Not satisfied?
google:
how to replace fuel injector site:blazerforum.com

 

Thanks, I will check there. And yes I have "Cruised" around a bit. I look for info you all supply any harm in that? I thought that what this forum was all about to learn. Again thats what I'm doing. Taking the info you all give and apply it to my situation and see it fits. This forum has help and save me time and money and I will keep on "Cruising" along of course unless you have a problem with that and I would suggest you contact me via my email address so we can discuss it. (Dman00194875@msn.com).

Thanks for the help and info.
Dennis

 

gmpartsdirect.com now has a kit to upgrafe from the poppet valve injection to MPI. Kit comes with the spider, bracket and o-ring kit. Part number is PK12568332 (SCPI to MPI upgrade kit) and was $239.90 with shipping.
Shipping was a little high, but the total package price was still a good deal to get rid of those POS poppet valves.
Looks like a good Thanksgiving weekend project to me!

Installation went pretty smooth this weekend on installing the MFI conversion. Taking the upper intake manifold off revealed 113k miles of carbon build-up and soot.


Removed the old Sequencial Central Port Fuel Injection Spider from the lower intake manifold and realized how much crap was built-up on the entire assembly.


Here's a couple of close-up's of the business end, better know as the infamous "Poppet" valve that gums up over time.


You can see the spring-loaded ball at the end of the poppet valve.


Here's a shot of the underside of the upper intake manifold. The build-up looked like tar from inside of a chimney.


Spent some time thoroughly cleaning the lower intake manifold before putting the new injector bracket on that came with the kit.


Here's a shot of the new unit fresh in the box. One strange thing I did notice was that the injectors were facing the wrong way. I had to rotate all the lines 180 deg. around to get it set up properly.


I inserted the injectors into the lower intake manifold holes according to the cylinder numbers. The new injector had the cylinders clearly marked so as not to screw up. I used a heat gun to make the injector lines a little more flexible to get the body of the injector to snap down into the mounting bracket. The fuel lines are real stiff, and at one point I though I was going to kink them, so I played it safe and got them more plyable with the heat gun set on low.
Here's the final shot with the new unit installed before closing her up.


I used a little silicone grease on all the new gaskets and o-rings which made re-assembly go a lot easier.
One thing I want to mention here is it is best to buy the intake manifold gasket set from your local auto parts store just to get the two fuel rail O-rings that go at the junction between the fuel rail and the incoming fuel lines by the firewall (rear of engine). Unfortunately, you cannot just buy them seperately. Maybe the dealer might of had them.

On a difficulty scale of 1-10, this probably rates around a 6 or 7. You just need some $, time and patients and your there.
We'll see if the gas mileage goes up from the current 15 MPG city. On the plus side, cold weather idle is already noticeably better. We'll see if there are any other tangible benefits from this conversion. One thing is for sure, the Butt dyno already likes it ;-)

 

*Moved to 2nd Gen Tech* - Please read the forum section descriptions and choose the section that is most appropriate for the topic you intend to post. This helps to keep the forum orderly so others can find things more readily as well as allowing others to find your post to help answer your questions.

 

Tank you, very good explications!

 

Hey guys! I too just installed this new spider this weekend.

After 1 day of trouble free driving, the new spider unit itself is now humming loudly upon pressure buildup prior to start up. This only happens if the fuel has not bled back into the tank so basically if i park it for a couple mins and start back up again a minute or so later, it hums and actually vibrates to the touch.

I informed the mechanic that installed it and he contacted a few mechanic friends of his that work for GM and was informed that this is a common thing with these new spiders? One mechanic told him he's installed about 8 of them for people and have all said the same noise began.. they recommended a couple fuel pressure adjustments that seemed to work every time for them so I will find out in a day or two is this is the case and post here for future reference for anyone needing piece of mind.

Has anyone else experienced this?

 

I have an 03 blazer 4.3 and it needs the spider injection replaced. I have a spider injector from a 2000 blazer 4.3l. I know they look different. Can I use the 2000 spider on the 2003 motor and what do I need to do to make this happen. Thanks

 

You can use the older SCFI injection spider in the newer engines, but I wouldn't advise it as it is a downgrade in reliability new SCFI vs. new MFI. I would NEVER recommend installing a used injection spider in these engines.

 

Its going into a winter vehicle. What's the best site to get a new one cheap. Can't find one under 400. This one off the 2000 works. Does it bolt right in? The injectors don't look the same.