Changing injectors........need help

Captain Mark

New Member
Oct 28, 2002
I got an excellent deal on some 38#'s and a "like new" SMC alky kit this weekend. I'm still trying to stay with the stock turbo for now. Here's my question:

How hard is it to replace those fuel injectors. Can someone walk me thru it?

Doesn't look too hard, but just wondering if there is some little things I need to look out for.

Thanks in advance.:)
You'll find a detailed procedure outlined by Scott Simpson HERE If your O-rings are hard or damaged, you'll need an injector seal kit. I got a kit at Advance Auto (Part #800-922 PSA I think).

I experienced a brain fart the first time I did this: Used spray SILICONE :eek: to lubricate the O-rings on the bottom of the injectors and the injector seats :( My O-2 sensor went out immediately....A master mechanic friend of mine recommended ordinary motor oil for lubrication, it works well and does not affect the O-2 sensor.

I take each occasion of injector change to inspect the injector harness on the fuel rail while its easy to see....Take care to locate the injector clips so they do not damage the wiring harness after installation.

Took three hours with a long lunch break in the middle :)
Some kind of pertroleum jelly works really well getting them back in and seated without much fuss. If you pry the rail up as you go around it, the thing should pop up with the injectors attached. When you stick the new squirters in and are seating the rail, make certain they are all in their respective ports before you start putting any downward pressure on them. This keeps you from mucking up O rings. Take your time and be patient, the stockers have been in there a while and can sometimes be stubborn comming out.
You'll need a chip for those 38's. You cannot use your stock injector chip with them. I think 38's are weird like 009's.. yes you would get a great deal on them. getting a chip is going to be rough.. just an FYI. If I had to do injectors, I have but one choice..50's.. the time spent dialing those 38's'll wish you hadnt. I dont have any 38 lb images. have like 20 for 50's.. You may just want to leave the stockers in there, put the alky kit..sell those 38's and get some 50's. Before you go through the grieving process. A couple hundred bucks on chips..and still be far off.

Also not having direct scan will make your chip guys life almost impossible to get you what your motor needs.

The SMC kit, make sure its in alcohol all the time, if the pump is stored dry, it will go bad, since alcohol removes the lube..and once stored, the only way to store them is run tons of lubricant..for putting them up for storage. You may want to test fire it before installing it..just as a precaution.. would suck to spend 3 hours and it not work.

I know a deal is a deal.. but just think of gains vs consequence.. If you paid under 300 for both, you did well. More..ehhh...

Mark, ya know I never lead ya wrong...
Originally posted by Razor

Mark, ya know I never lead ya wrong...

Yes, I believe that or I wouldn't be on here all the time asking for your advice.:D

I got the alky kit, the injectors and 3 different Jay Carter chips burned for these injectors and alky for $250. It was hard to turn down, but now you are scaring me. I would hate to get those injectors in there and be unhappy with them. I am going to install the alky first, and see how that goes, then I will make a decision on the injectors. I may just trade them in on some 50#'s and forget about the 38's.
Great deal..woohoo.

You have the chip for the alky already on your stock injectors..if your car has an aftermarket fuel pump(walbro 307/340), you should have plenty on alky to get it down into the lower 12's.. once you have it running like this, then make your decision.

I dont mean to scare you, I just have seen so many times repeatedly with 38's, 40's, 42's the issues relating to dialing them in. On the 42's, few chip guys have a really good grip it appears on them.

But if you like the way your car runs on the stockers.. it will drive identical with the 50's. I know there are 57's currently available as well.. but to me, until I see the mass market with them..I stay with 50's which everybody has tried and have had great results.

Some things, i'm just set in my ways :).. whats that expression.. you first.. I never want to be the guinea pig.. whenever possible. I did this with alcohol.. and have been pretty successful using it. I went against the race gas grain. But on the engine mods.. i'm real careful. Easier to do what has worked for so many..than be first..

I blew up 5 motors on my Camaro with an ATI race blower.. I learned a lot, and different approach thanks to that $$$$ learning curve. My TTA has never had the motor opened..and it has been driven pretty spirited the last couple years :)

Cheers my man.. and Merry X-mas

Jector condition??

Mark, a headsup on any used injectors you buy...If they have had fuel thru them, and have been out of the previous engine for more than short time, especially in open air, they may be stuck shut. I get them here frequently after the new owner has put them in, and the engine won't run right.
Sure enuf, I find one or more stuck shut.... Some I can free up and clean.. others, it's the trash can....

Back under my rock!!
Happy holidayz!
:D :D :D Da man...

Gotta call Clay at Rand Tech today bout the lightning..

Choices, choices :)


About 20 months ago I bought a set of 40 pound green stripe injectors and two REDS chips (with 500 miles on them).

The new combination ran well in my TTA with a stock turbo and D-5, but burned extremely rich (O-2's 800-900+mv at WOT) at 7000 feet elevation, even with AFPR turned down. I didn't like the black soot under the tail pipe in the garage, and wanted to pass emissions too. So, I went back to stock until I found a set of 50's, they were the rave at the time.

I sold the 40 pounders and the chips at a small loss (manufacturer rated at 40 pounds per hour, but actually tested closer to 38 pounds per hour by guys I respected on the board-I think that is why they are known as 38# injectors here on the board.)

The 50 pounders are a much better choice for our mild performance goals/upgrades, in my view. Razor has chips that work for 50 pounders. Also, the MAF extender and translator works great with them. The extender and translator might work well with the 38 pounders too. I don't know if TurboBob has an extender for the 38's or not. If he does, I'm sure he's nailed the parameters down and it will work well for you.

The things I like best about the Extender and translator combination -aside from easy tunability- are the $$ savings of running a stock FPR at 45 psi and the reduced need/dependance on a larger fuel pump over stock (bigger opening in the injector requires less pressure to get the same volume of fuel, compared to a smaller injector openeing -remember, I'm thinking only mild MOds, not full out racing here)

The combination with the greatest potential (for us looking for modest upgrades and performance) is prolly the 57 pounders with the extender and translator plus. If TurboBob is making an extender for the 57 pounders, thats the way I'd go.

Only regret (NOT intended as a flame here :)) is the extender version with the "fast frame rate" does NOT give you Malfunction codes. The multiple reports of the TPS, O2 and KR in the "fast rate" version are revealing and VERY useful in tuning. If I had it to do over, I'd get ahold of TurboBob and have him make a chip that sent Malf codes instead of Prom ID in my "fast rate" extender chip. I don't need the prom ID reported every second....I can write the prom ID on the chip ;) and tell Turbolink which chip I'm using....I'm sending RAZOR a check this week for a chip to install when I want to check the Malfunction codes :)

HTH :)

Chin up Mark....All this is not to say the 38 pounders won't work perfectly for somebody....Hot air guys use them to full advantage all the time :)

With injectors and Alchy in the offing, I'm sure you're going to do one thing at a time....Right? Stay stock for now and put the Alchy kit on there and get it right before you change injectors. You may be happy without the injector change :)
Originally posted by lburou
With injectors and Alchy in the offing, I'm sure you're going to do one thing at a time....Right? Stay stock for now and put the Alchy kit on there and get it right before you change injectors.

That's the plan. Take it slow and pay attention!

As usual, thanks boys.:cool: