HT4100 4.1, 4.5, 4.9 Discussion, Fuel Injectors 94 Deville 4.9L in Cadillac Engine Discussion; I did some searching but I still have some questions about replacing one or more injectors on a 94 Cadillac ...
I did some searching but I still have some questions about replacing one or more injectors on a 94 Cadillac Deville with 4.9L engine and 140K miles. We want to get around 30-40K more miles out of this car and we only use it for road trips so this means about 10 years.
I recently replaced the head gaskets and also removed the fuel rails and cleaned the intake before reassembly. (PS thanks to everyone here who helped me, the suggestions from this website helped alot). The car runs great except I now notice that the fuel used is about 20% more than what the computer indicates. I kept careful records over a recent 1000 mile trip. It used to get 24-25 highway mpg's but on this trip it only got around 21. These mpg's are from my own calculations not the computer.
I checked the regulator with engine running and it does not leak. I will check the injectors this weekend by pulling the fuel rails up and energizing the pump. I suspect that one or more injectors will be dripping. So here are my questions:
1. Is it best to replace all injectors if one or more is leaking?
2. Do I need any special tools to take the injector off the rail? And to replace.
3. Do I need any other parts besides the injectors? I put new o-rings on when I did the head gasket job, can I reuse these?
4. What is the best price I can hope for and where do I get injectors at this best price!
Just did my '93 eldo 4.9 last spring. My opinions in order of your questions.....
1-Yes, but 8 injectors will get spendy. Use AC Delco OEM parts to be sure. Some people have reported good luck with Accel but I've been burned too many times by aftemarket parts to take that chance.
2-No. Mine were held on by clips. A small screwdriver popped them loose. I reused the clips. Some years and models don't even have clips and are held in place by the fuel rail.
3-No. New injectors will have O rings or you can reuse the new ones you have
4-I lucked out and got a brand new set of 8 on Ebay for about $175, IIRC. They do turn up there from time to time. Best prices I got otherwise were about $70, IIRC, each from www.gmotors.com or www.gmpartsdirect.com.
All this being said, before you disembowel the beast are you certain of you figures? How does it restart after running then sitting for a few minutes? Leaky injectors will sometimes cause hard starting mimicking a flooded condition. How is the mileage in general compared to previously?
hey caddy scout.....did you ever get around to changing the injectors. I have to replace one in my 94 deville 4.9 and wanted to know how hard it was? i recently found out how and did the fuel injector test and cut each injector off for 2 secs and found that the #5 injector was not firing. well i just wanted some info before i got into it. Thanks
just because you shut off the injector doesnt mean it isnt working , check for spark too ...if that cylander isnt getting spark then it wont make any diffrence what you do with the injector ...i would also pull that plug out and inspect it and possibly run a compression test on that cylander since if it is indeed number 5 it will be easy to get to ....
Ok I pulled #5 spark plug and it was black and smellled like gas so I replaced and no help. Why would it smell of gas if the injector isnt working? I also changed the plug wire to make sure that wasnt bad...same. So I then pulled #5 injector and #7 injector power and switched them and then #5 plug would run the #7 injector so I know its getting juice. So about the only thing left to do is change the injector. I called discount auto and they want 91 bucks for one. I have a buddy that runs a junk yard and he told me $10 I think im go with that to make sure its bad first and if it is ill put a new 1. By the way does anybody know the correctgap for the spark plugs? Thanks again
well it sounds like an injector to me , but after you saw the price on a new injector you now see why i wanted to to check everything else on the cylander ....they arent cheap and i woulda have hated to see you waste money ....but def sounds like an injector to me too .....that junkyard unit might work for you , for 10 bucks you cant go wrong ....corect gap for your plug casn be found on the emmisions label on the underside of your hood
I put a set of the injectors in from fiveo a couple years ago and was very pleased with the delivery and price. And lifetime warranty (at least when I got mine, if they still do that) is well worth it. I think they are a great supplier to work with. The stock injectors are 18lb and the Bosch replacements are 19lb. But that is not proving to have any deterimental effects to the 4.5 or 4.9's. All replacement injectors except for Cadillac injectors are 19lb.
In all honesty the only place it MIGHT show up at all (which isn't) is at WOT you might have a slightly richer mixture. Else the ECM compensates just fine. In my 91 (sold now) I had always kept close tabs on the integrator/block learn and it was just fine coming in around 128 +/- 5 most of the time, well within GM spec.
well thanks everybody for the info and when i get some extra cash I will put a complete set in. I will change out the 1 this weekend depending on what this tropical storm does off the coast.....its freakin me out just sittin there picking up speed!!! If it goes away I will change it and get back to ya. By the way could it be messing something up by driving it and that injector not firing? Ive heard it can clog up your cat converter...is that true? Thanks again.
I picked up 8 injectors (rebuilt) for 224.63 they come with a 10 year 100k warranty... They are OEM injectors and they work great! Stuckey Bros. Parts CO. 843-558-2541 I could not beat the price or warranty anywhere... They have been in my 92 Eldo all summer and not problem one.
(don't take this as a flame, by all means I am not, I just hate seeing people get ripped by unscrupulous people selling junkyard junk as something it is not)
There is no such thing as rebuilt injectors. There is CLEANED injectors, but you CANNOT rebuild them. They are crimped together and cannot come apart without destrution.
Do not waste $$ on so called rebuilts, they don't last, they are just someone elses junk. I could go into a junkyard, yank every injector, make a custom spray bench, ohm the injectors and prove the spray is good and go into business selling "rebuilt", that is all they are, if you are lucky enough to get at least that done. At least there is a warranty.
fiveo is selling VERY low mileage takeouts, for the same price. You know they came out and weren't 200K mile specials that someone ran the cheapest gas through they could. Mine were from Ford 4.6's, had est 1K miles on them. They were in good shape, likely was the case.
fiveo's is lifetime warranty and about the same price. I know, 10y or lifetime, likely the samething....
It does seem the Bosch injectors are good quality, you don't see many fail. My 90 Aerostar had them, and 275K miles (with 3.73 gears and 25 in tall tires), so there is a LOT of firings there. Most are the orange top Bosch injectors that get sold.
New Accel injectors at Summit were around $230 last year, so that is also a good choice, they are new too.