Can this '89 really need injectors again?
08-07-2009, 12:32 AM
#1
Heel & Toe
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Can this '89 really need injectors again?
Have an '89 with very low miles. Wouldn't start last summer and after several weeks of frustration, finally pulled it apart and had the injectors cleaned and re-speced & replaced 3 that were bad. Car ran for 60 miles (yes, sixty), then quit again. Sat all winter and now will only start when the #1 injector cap is off. The mechanic says it needs all the injectors replaced. Can this possibly be true?
08-07-2009, 07:15 AM
#2
Racer
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When you say "quit" again, this means it won't crank? It cranks and won't fire? It starts then dies? Be more specific.
When is the last time the fuel filter, rotor, plugs, cap, wire where changed? I would check out all of the simple ( and cheap) stuff first and go from there.
The person who did the injector repair last year might not have installed the same type of injector, or the the older ones that were not replaced decided to now crap out.
While I was there, I would have replaced them all but thats a moot point now.
The more info you give here, the better chance of a diagnosis.
When is the last time the fuel filter, rotor, plugs, cap, wire where changed? I would check out all of the simple ( and cheap) stuff first and go from there.
The person who did the injector repair last year might not have installed the same type of injector, or the the older ones that were not replaced decided to now crap out.
While I was there, I would have replaced them all but thats a moot point now.
The more info you give here, the better chance of a diagnosis.
08-07-2009, 08:06 AM
#3
Safety Car
If they replaced the bad ones with OEM style Mul-Tect's the remaining ones could very well be bad as well as the new ones. The ethanol in today’s fuel eats up the insides causing them to fail. Call Jon @ FIC get a new set of Bosch lll's. You won't have to replace them again.
08-07-2009, 08:47 AM
#4
Melting Slicks
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16-'19, '21-'22-'23-'24
Early, pre-92 multi-techs
are not resistant to the alcohol in the fuel now. If the repair was done using OEM/GM parts those replacement injectors are also not resistant to the alcohol in the fuel now. Don't ask me why GM didn't change the design of the early injectors, but the only OEM injectors that are resistant to alcohol are the injectors by application after 91.
That's what I learned after doing some looking when my C4 needed injectors. I need twice as many so the cost was going to be a big hurt and I didn't want to have to do it more than once. Also, on the early OEM injectors, they don't react well to "cleaning" according the GK.
That's the back ground on the early multi-techs. I would trouble shoot the issue from the basics. You know, spark, fuel, then KOEO scan to make sure all the sensors for start up are reporting into the ECM. Maybe pull the plugs to see what was going on when the car did run....could be something useful there? JMHO.
Tom
That's what I learned after doing some looking when my C4 needed injectors. I need twice as many so the cost was going to be a big hurt and I didn't want to have to do it more than once. Also, on the early OEM injectors, they don't react well to "cleaning" according the GK.
That's the back ground on the early multi-techs. I would trouble shoot the issue from the basics. You know, spark, fuel, then KOEO scan to make sure all the sensors for start up are reporting into the ECM. Maybe pull the plugs to see what was going on when the car did run....could be something useful there? JMHO.
Tom
08-07-2009, 09:05 AM
#5
Instructor
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Fuel contamination or age can always be something to look at. Had my 85 in for some stuff this spring and after injector check, Tech said they were perfect and wanted to know how this was possible for it has 97,000 miles on it. My secret is FI cleaner every tank. A little expensive, but worth it in long run. For the last 5 years or so I have been running Sea Foam. Price has doubled so I wait for sale, sometimes 2 for one. Total system cleaners and such can be a good thing, as a maint. thing, but when you are already having injector problems it can be a diagnostic nightmare to be cured by really sharp Tech. There are places that will analize your fuel and can just about tell you what station it came from for $ 25 bucks or so. It's just how deep you wanna go. Gimme an 850 double pumper.
08-07-2009, 10:43 AM
#6
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If it's the injectors don't work with anyone except FIC. I usually don't encourage one vendor only but you will never get better service and more truthful information then from Jon.
There is a thread form him at thetop of either this or in Tech and performance.
89 red coupe
There is a thread form him at thetop of either this or in Tech and performance.
89 red coupe
08-07-2009, 11:55 AM
#7
Heel & Toe
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Hey guys, thanks for all the quick responses.
Sorry I wasn't more specific up front. The car cranks but won't fire. There's plenty of spark and fuel pressure is 42 pounds at the rail. It will fire with starting fluid, but otherwise acts like the injectors won't open. We've already been through all the usual stuff, changed out filters and sensors and relays. Since the only diagnostic code we can get it on it is something about the coolant, even thought it might be the ecm, but no. Hence, we're back to the injectors.
Quite by chance, we tried to start it after pulling the cap off the #1 injector and it started right up. Put the cap back on and it's back to cranking again. Repeat with same results. That's when it went to the mechanic, who says it needs ALL injectors replaced.
And after finding this forum and hearing from all of you, it sounds like replacing them with FIC Bosch injectors is the answer to our problems. Guess I better call Jon..............
Sorry I wasn't more specific up front. The car cranks but won't fire. There's plenty of spark and fuel pressure is 42 pounds at the rail. It will fire with starting fluid, but otherwise acts like the injectors won't open. We've already been through all the usual stuff, changed out filters and sensors and relays. Since the only diagnostic code we can get it on it is something about the coolant, even thought it might be the ecm, but no. Hence, we're back to the injectors.
Quite by chance, we tried to start it after pulling the cap off the #1 injector and it started right up. Put the cap back on and it's back to cranking again. Repeat with same results. That's when it went to the mechanic, who says it needs ALL injectors replaced.
And after finding this forum and hearing from all of you, it sounds like replacing them with FIC Bosch injectors is the answer to our problems. Guess I better call Jon..............
08-07-2009, 01:35 PM
#8
Burning Brakes
Your injector coils probably are toast. What happens is they develop shorts which decreases the resistance and increases the load on the ECU. If you have too low a total resisance on a particular bank, the resulting high load will cause the ECU injector driver to overload and shut down. Unplugging injectors will remove some of the load allowing the injector driver for that bank to operate again.
08-07-2009, 08:28 PM
#9
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St. Jude Donor '09
Hey guys, thanks for all the quick responses.
Sorry I wasn't more specific up front. The car cranks but won't fire. There's plenty of spark and fuel pressure is 42 pounds at the rail. It will fire with starting fluid, but otherwise acts like the injectors won't open. We've already been through all the usual stuff, changed out filters and sensors and relays. Since the only diagnostic code we can get it on it is something about the coolant, even thought it might be the ecm, but no. Hence, we're back to the injectors.
Quite by chance, we tried to start it after pulling the cap off the #1 injector and it started right up. Put the cap back on and it's back to cranking again. Repeat with same results. That's when it went to the mechanic, who says it needs ALL injectors replaced.
And after finding this forum and hearing from all of you, it sounds like replacing them with FIC Bosch injectors is the answer to our problems. Guess I better call Jon..............
Sorry I wasn't more specific up front. The car cranks but won't fire. There's plenty of spark and fuel pressure is 42 pounds at the rail. It will fire with starting fluid, but otherwise acts like the injectors won't open. We've already been through all the usual stuff, changed out filters and sensors and relays. Since the only diagnostic code we can get it on it is something about the coolant, even thought it might be the ecm, but no. Hence, we're back to the injectors.
Quite by chance, we tried to start it after pulling the cap off the #1 injector and it started right up. Put the cap back on and it's back to cranking again. Repeat with same results. That's when it went to the mechanic, who says it needs ALL injectors replaced.
And after finding this forum and hearing from all of you, it sounds like replacing them with FIC Bosch injectors is the answer to our problems. Guess I better call Jon..............
08-07-2009, 09:43 PM
#10
Race Director
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Your injector coils probably are toast. What happens is they develop shorts which decreases the resistance and increases the load on the ECU. If you have too low a total resisance on a particular bank, the resulting high load will cause the ECU injector driver to overload and shut down. Unplugging injectors will remove some of the load allowing the injector driver for that bank to operate again.
Call Jon 
08-08-2009, 12:02 AM
#11
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