Injector removal

[handstjg]

Anyone have an article on removing and replacing the injectors on an 86 L98?

 

[caddy]

How about on a 94 LT1?

 

[The Car Whisperer]

The factory service manual has this procedure in detail. Not a difficult task to do, just need patience and good mechanical skills. I found the toughest part was disconnecting and reconnecting the fuel lines at the front of the fuel rail. Did it all in a weekend though. Are you just replacing the injectors? I would replace all the o-rings that go into the fuel rail assembly itself while you have it apart.

 

[handstjg]

Whisperer,
I will replace anything that isn’t nailed down once I get in there, vacuum lines, fuel pressure regulator, "O" rings, etc. etc…if I can touch it, it is gone. After 22K miles in this heat I am not taking any chances. My luck, next month I get to do it over again for some $2 part. Did you replace the injectors or have them cleaned and flow tested?
Thanks.

 

[The Car Whisperer]

I replaced them with a new flow balanced set. I think you're doing the right thing to replace every o-ring and seal while you have it apart. It's not just the milage, but the age of the car that I considered when I changed my injectors. Are you doing it yourself?

 

[handstjg]

Yes, I just got the vette back from the dealership. When did they legalize that type of prostitution? I had a code 34 and wouldn't believe my instincts. It cost $245 for labor to replace 3 items that couldn’t have taken 30 minutes to install. It still starts hard after it sets for a while. Rather than pay to have them to replace parts, and trust me they don’t have any better idea than I do what to replace, I will do it myself from now on.

Do you know if there is a check valve in the fuel system? The fuel pressure is 37 lbs. at idle which is within specifications. When you turn on the key it jumps up to 30 lbs. before I start cranking.

 

[JonM]

This won't tell you how to remove...but I think it will help a bit.

http://www.corvettemagazine.com/1999/nov99/injection/fuelp1.asp

 

[The Car Whisperer]

I had a hard starting problem until I replaced my injectors. I had one that leaked a bit and would foul out a plug. I'm not sure about a check valve in the system, I think the regulator holds the pressure in the system.

 

[handstjg]

Might as well replace the regulator also while I am in the mood. Which injectors did you use?

How do you like the Blisteins?

 

[The Car Whisperer]

I used injectors from .Marren Motorsports , they send a set of injectors that have been bench flow tested, balanced flow checked and blueprinted.They also offer a rebuilding service. Put them in about 7 years ago and no starting problems since. I also replaced the cold start valve, was difficult to find 7 years ago and I don't think you can get them anymore.
If you need any GM part numbers for seals etc I think I have all that stuff in my files.

The Bilsteins are good, I think they may be getting a little soft now, I put them in in 1996, they only have about 20,000 miles on them since then but I see a little bit of deterioration in ride control on rough surfaces.

 

[The Car Whisperer]

Here's the part numbers of the items I used when I replaced my injectors:
Replacement Injectors AC Rochester Products P/N 17090882
O-Ring Kit P/N 17111696 (Covers Crossover Tubes and Cold Start Valve)
O-Ring, Fuel Feed P/N 22514722
O-Ring, Fuel Return P/N 22516256
Fuel Injector Seal Kit P/N 17113544 (Includes 16 O-Rings to Seal Injectors)
Cold Start Valve Pkg. P/N 17110860 (Includes Valve, Top, Bot & Feed Tube O-Rings)
Plenum Gasket Kit P/N 12508751
Runner Gasket Kit P/N 10174951
Gasket, Throttle Body to Plenum P/N 10105379
Fuel Filter AC/Delco GF481 OEM 22056129 PKG25055052
ALL OF THE PART NUMBERS ABOVE ARE GM
I also installed:
ADJUSTABLE FUEL PRESSURE REGULATOR, Mid America Designs P/N 17705
While I had the Plenum and runners off I glass bead blasted them so they looked brand new.
I can email you some photos of the completed engine if you like. After the plenum beadblasting, looks real nice.

 

[8388]

Make sure to put a dab of oil on the O rings before installation.

 

[The Car Whisperer]

Forgot about the oil, just assumed everybody knew that. You definitely need the oil or you run the risk of tearing an o ring. The oil makes the o rings slip into place nicely. Just a little is all you need.

 

[bossvette]

Do you know if there is a check valve in the fuel system? The fuel pressure is 37 lbs. at idle which is within specifications. When you turn on the key it jumps up to 30 lbs. before I start cranking.

there is a check valve in the fuel pump which often leads to hard starting problems. the pressure regulator varies the fuel pressure according to load(vacuum signal) a adjustable regulator is OK if you plan on modifying your engine, but not needed for stock systems

 

[The Car Whisperer]

I just came across this web page about injector replacement - http://www.thirdgen.org/newdesign/tech/injectorswap.shtml May be helpful.

 

[Edmond]

I replaced them with a new flow balanced set. I think you're doing the right thing to replace every o-ring and seal while you have it apart. It's not just the milage, but the age of the car that I considered when I changed my injectors. Are you doing it yourself?

Hey Car Whisperer,

What differences did you notice in driving quality? A little quicker? More responsive?

I'm thinking about taking my injectors out this winter to have them cleaned and flow tested.

 

[The Car Whisperer]

First thing I noticed after I changed out the injectors was that the engine started right up. Before I changed them it would crank a while before it would start, especially after the engine was hot. Second thing was a nice smooth idle. The throttle was more responsive, and it definitely felt stronger off the line. Not a tremendous increase in power but I definitely noticed a difference.