I own a 2000 GMC Jimmy 4.3 2WD. Irrelevant but anyhow, I am curious what you guys think about this idea of cleaning fuel injectors. I wanted to clean mine and started looking into the tools alone necessary and calculated $200 easy, well, thats not happening. So I started to think why it is done through the fuel rail like it is, and determined that was the fastest way to get a concentrated cleaner in the system. Shops want a 30 minute procedure, cant add a concentrated cleaner into a tank of gas and run it empty at a shop, cant drain the fuel system, not feasible or safe. But for the DIYer, why cant you just run your tank empty, pour the cleaner the pros use into the fuel rail in the fuel tank, start it up and run it till it dies. Would not even have to plug the return line because the cleaner will return and cycle back through. If you are familiar with the process through the fuel rail you know the setup just bypasses everything from the motor back to the fuel tank, but simulates everything it is bypassing, pressure, etc.. I have come up with no reason this would not work. The cleaner would not damage anything it does not already come into contact with anyway, such as rubber, steel, aluminum, seals, and what not. There are no materials from the gas cap to the motor that there are not from the fuel rail into the combustion chamber. We all know that these professional cleaners will work to no ends better than the crap you add to your gas. I think the whole setup into the fuel rail was created as on only means for a professional shop to clean injectors on vehicle. Chime in and let me know.

 

I use Chevron Techron at every oil change and have never had to do a "professional" injector cleaning. Even on vehicles with injector pattern issues, a double dose of Chevron Techron had them running MUCH better after a single tank.

I wouldn't suggest trying the process you detail above. Those cleaners are VERY aggressive, how else do they clean in such a short period of time. The components in the pump are not spec'd for that.

 

Thanks for the reply. That is what I am not understanding, or should I say am being cautious about. I am aware the cleansers are aggressive, but is any part of the fuel delivery system really more delicate than the injectors themselves. It would seem if the injectors could handle the cleaners, so could the pump. No different materials in the fuel pump, than the injectors. I agree with the double dose of Techron, but only as preventative maintenance. This is a retired construction vehicle with 200K.

 

There are some materials in the tank side of the fuel system that are different from those used in the injectors. The hose from the pump to the top of the tank is one thing that I would be worried about. The sock on the bottom of the pump would be exposed to the cleaner for quite a while as well.

When the cleaners are used directly into the fuel rail or in this case, the spider, they are only used until they run out, then the standard fuel system is reconnected and when you start the engine again, the rest of the cleaner is flushed out.

I have never liked the "professional" cleaners for these engines. I have never seen one actually work as advertised due to the configuration of the fuel systems in these trucks. Your's being a 2000, you have the 6 individual electronic injectors along with 6 pressure actuated poppet nozzles. The poppet nozzles are what gum up and start to leak. Over time, the nozzles themselves become worn by the buildup and even after cleaning, they do not spray properly.

I would start saving up to replace the injection spider if you really think that it is hurting performance/efficiency. The newer design MFI spider takes the problematic poppet nozzles out of the equation, moving the electronic injectors right down to the intake runner.

 

I have seen the new MFI kit, think I found it for $165 or $265. Was slightly worried about the complexity of doing this. Have you done it to yours. Got the basic tools, torque wrench, etc. Just concerned about how difficult it is. Especially putting the new spider in place, bending the lines and kinking them, seating the injectors properly and not knowing if any are leaking in there after I finish. How can you check them for leaking before putting the plenum cover back on?

 

I did it to my old '00 Bravada in a few hours. The hardest part is getting the external fuel lines removed. Fight the temptation to just bend them! They can be a royal pain to get back into the spider.

 

Kyle do you have a link to the upgrade kit?
or remember who makes it? i also have a 2000 blazer and would like to look at that.
thanks
Barrett

 

Search for "MFI+upgrade" without the quotes and you'll find the PNs listed. GM change the injection system in sometime in 2002.

 

best way Ive found to clean the whole engine next oil change buy a couple bottles of "Sea Foam" its a universal engine cleaner from diesel to 2 stroke. put a little in your fuel tank another dose in your oil then finally slowly add it into your intake with the engine running. I did it to my 96 jimmy its got 276000 miles it got rid of so many little problems I was having

 

Thanks for the info Kyle
Barrett