Hi guys! I'm new to thirdgen and have some questions. I'll introduce myself; my name is Dustin. Now to my question. 91 Firebird with a 3.1L V6. Went to look at it yesterday, guy said 500 and it's mine so I took him up on it. Right off the bat I knew what was wrong with it. Started up and idles real rough (guy replaced timing chain and gears, but didn't do it properly so timing is off). Give it gas and it will bog a little and definitely doesn't reach full power. I had this same problem when I bought my 91 Firebird with a 305 V8 in it. Only the dealer had tried everything then cleaned/replaced the injectors and it ran like new. I was going to start right with the injectors because I am almost certain that this will fix it.

My question: How difficult is it to replace the injectors? I am a mechanic and have been working at a local shop for about 2.5 years and prior to that I worked construction for 6 years. This car will need lots of work exterior and interior. Anyone have any how-to instructions or advise for doing the injectors? I would replace them and fix the timing and most likely replace the water pump as the vehicle has 114k miles on it.

Not a spot of rust though! Does anyone know of a site where I can order parts as well? I was going to go to the local junk yard and pull parts off a camaro and trans am of the same year for the interior, but would prefer new.

Thanks in advance!
Dustin

 

Injectors are pretty easy. Dump the pressure at the Schroeder valve and unbolt the fuel rails. Unplug the wiring harness and just pull them out and replace. As for parts, you can look on this site. Thirdgen Ranch is a sponsor and they have lots of stuff. Then any of the resto companies out there and of course e-bay. Just Google what you need. Another site sponsor, Southbay Fuel Injectors are awesome people to deal with. Give them a shout for your needs.

 

Thanks for the response! I figured as much it would be fairly straight forward and simple. Going to head over tomorrow and tow the vehicle over here. The wonderful thing is for 500$ I left myself with a lot of play room for in case more work needs to be done. I am 99% sure the injectors need to be cleaned or replaced (I would rather replace them).
For the timing I am thinking of just replacing it all together. I have no idea what the kid who had the car before this man did. I would rather not and hope I won't need to, but it's not difficult to set the timing right the first time (my opinion).

If I choose to just clean the injectors, what would you recommend as a cleaning agent for it?

 

I have never cleaned any, only replaced. My son works for Firestone and they use something with their trade name on it, but he says the stuff you get from your local parts house will work just as good.

 

Keep in mind that depending on the condition of your injectors, these agents can be just a temporary fix. If you are going to use one, we like either Seafoam which is EPA registered or Techron which is made by Chevron...2 reputable companies.

 

Those will be Multec injectors, in which the coils short out. Better off replacing them with a set of reman Bosch.

Also, getting to them is a little more involved. Need to pull the plenum off to get to them. The intermediate intake (runners) can stay in place.

Do not remove the fuel hard line from the injector fuel block. Unclip the brackets that hold the hard line in place to get the fuel block up and out. The reason is that it is very easy to strip out and/or cross-thread the hard line fitting into the aluminum fuel block.

Note that the TB in stock form has coolant running through it. So need to decide whether to open the coolant system or unbolt the TB from the plenum. Could also be lucky and the coolant has been bypassed.

RBob.

 

Thanks for the tip! I wouldn't want to touch the hard lines because I know how much of a pain it can be stripping/cross threading parts... Done it millions of times working on cars and bikes! Never any fun...

So I will do what I planned on doing and replace the injectors. I will most likely order them from SouthBay and I am hoping that fixes the problem. Minus fixing the timing of course! If the injectors do not fix this, then it's time to replace the other things that got replaced on my 305. Not too worried about it as I have about 3 weeks of being in a sling to work on this and can do decent torquing with my left arm!

Thanks again!

 

Hey Firebird_305 if you do decide to purchase a set from us and you order from our website, don't forget to include the promo code tg11 at checkout so you can receive 10% off! Any questions, give us shout.

 

I am looking to order the injectors today. I have seen ones offered for a variety of lbs (19, 22, etc..) which kind do most recommend? For the 3.1L I would assume the 19 or 22 lb would be fine, but I have seen all of them say "Direct Fit" and really have a limited supply of $$ to work with. I would pull the old ones out, but I am awaiting a title so I currently don't have the vehicle. Just trying to order what parts I know I need in advance to make it easy sailing

 

19-22lb are going to be too big if you are just replacing the stock injectors. You can use either the bosch 15lb or 17lb. The set of 6 is $130.99 plus 10% off. Any other questions please give us a call.

 

SouthBay, you guys rock!

 

Thanks! We try!


www.southbayfuelinjectors.com
516-492-6504