1989 Injector problem?
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From: Texas City Texas
1989 Injector problem?
Help! I suspect that I'm having injector problems. After sitting a day or two, I experience hard starting. It will hit and run for about 2-3 seconds then die. After doing this 3 or 4 times, it starts and seems to run fine with a somewhat rough idle at 600 rpms. Plugs are new AC RapidFires. It seems to accelerate as normal, but I'm worried about a no start and tow home. Everything under the hood is original(32,000 miles). I know that the original owner regularly used fuel additive. I've read several posts about the lousy injectors in this 1989 and the problems when using additives in these injectors. Should I just replace them and what should I buy for a stock engine. I consider myself a good mechanic, but you Guys have impressed me many times with your knowledge of C4s. What would you do? Thanks
Le Mans Master
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From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
I know its been said many times before, but learning and using the forum SEARCH function for such questions and information is the way to go... Search, Advanced, Archive posts, and pick C4 forum... It will save you time and give you enough info to work from...
Melting Slicks
Joined: Apr 2002
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From: St. Charles, MO Route 66 Corvette Club
I support the comments of vinnie above. Here is a very long thread on replacing L98 injectors that you could locate doing a search:
http://forums.corvetteforum.com/show...post1560357682
Hope this will get you started on the right foot!
http://forums.corvetteforum.com/show...post1560357682
Hope this will get you started on the right foot!
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
The "crappy injectors" on my 1989 are still working perfectly. You need a multi-meter and a fuel pressure gauge to trouble shoot injectors. Don't assume they are bad. They certainly aren't all bad.
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From: Texas City Texas
1989 Injector problem?
Thanks for all your replies. I do need to ohm and pressure test first, but I'm thinking of the years this car spent as a trailer queen with a start once a month for exercise. I remember when I pulled them out of my old Honda for flow and clean. It really made a big difference.
Thanks again for the response and expertise of this Forum.
Thanks again for the response and expertise of this Forum.
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From: Texas City Texas
1989 Injector problem?
Well, I did ohm the injectors(need gauge to check fuel pressure) and they are all 16.5 +-2 ohms. However, it seems to start and run smoother after just unpluging then pluging them back...FYI
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
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Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
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From: Texas City Texas
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From: Texas City Texas
No, the plugs are new rapid fires. I say new because they were replaced about 2 years ago, but now only 3000 miles on them. I think the biggest problem is that it needs the cobwebs blown out from sitting too long.
Racer
Joined: Apr 2001
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From: South Haven Michigan
What are you talking about with "injector filters"? There is a main fuel filter along the frame, but not individual filters on every injector. It is the windings that can degrade inside the filter and then they short out, but your ohm readings are fine, so this is not the problem.
Le Mans Master
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From: seattle WA
Ohming the injectors only gives you a picture of the injector coils.....but that's not to say you still couldn't have leaky injector(s).
That's why you need to do the fuel pressure test. Another test you can perform is checking each injector with a noid light. On my 87 all injectors ohmed good, and the fuel pressure was good, but when I checked each injector with a noid light I found one injector with a bad pigtail connection. Since you say it seems better after removing and replacing the injector connectors (pigtails) it's quite possible you just have bad connections. But I wouldn't hold my breath on that take.
That's why you need to do the fuel pressure test. Another test you can perform is checking each injector with a noid light. On my 87 all injectors ohmed good, and the fuel pressure was good, but when I checked each injector with a noid light I found one injector with a bad pigtail connection. Since you say it seems better after removing and replacing the injector connectors (pigtails) it's quite possible you just have bad connections. But I wouldn't hold my breath on that take.
Melting Slicks
Joined: Apr 2002
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From: St. Charles, MO Route 66 Corvette Club
with Rick above. You could have clogged/dirty injectors too. If you use an injector cleaner on your Multecs, you are shooting yourself in the foot 
I have found that a small dab of Oxi Guard (available from Home Depot in electrical dept) placed on the electrical connection contact points helps keep electrical connections clean and working as designed. FYI only.
Le Mans Master
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
chemicals
with a car that age, and having chemicals sit in the fuel system, i would investigate the fuel pressure regulator diaphragm. my 86 with 130,000 miles had just begun to wisp fuel vapors out the vacuum port on the regulator, and since I had to take it off, I put a Holley regulator on in it's place. no more vapor, and steadier readings on the fuel pressure gauge.
It was interesting to note that the fuel pump was failing also, and the fuel pressure took a little time to recover after a rev. The gauge would fluctuate for each batch fire release.
After the new fuel pump went in, the fluctuations were non-existent
It was interesting to note that the fuel pump was failing also, and the fuel pressure took a little time to recover after a rev. The gauge would fluctuate for each batch fire release.
After the new fuel pump went in, the fluctuations were non-existent
Last edited by coupeguy2001; Dec 4, 2007 at 02:37 PM.
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From: Las Vegas Nevada
Hey guys I finally bought my first Vette about a month ago. I picked it up for real cheap cause the guy said the injectors need to be replaced. Maybe more than that though i think. When I start the car it starts right up, smells real rich. But after about 2-3 minutes it starts smoking REAL bad(white teary eyed smoke). If I let it run for 10-20 minutes in park it wont stop smoking until I get in and drive it, then the smoke goes away but still smells bad. When I let it sit in my driveway and i try and give it some gas, it smokes up my whole neighborhood. Could it be a blown head gasket? I have a 73 Charger, with none of these crazy sensors everywhere, maybe a sensor? HELP?!
Safety Car
Joined: Jan 2006
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From: Mt Laurel NJ
St. Jude Donor '06-'07
I would check the Coolant Temp Sensor, could be your problem w/ the idle, but the white smoke sounds like a bad head gasket. Is the car useing or losing coolant?
You need to buy a Factory Service Manual (FSM) to figure out what is going on w/ your car, any car smoking like you describe has a serious problem. Is the car auto or stick? If it is auto, could it be sucking trans fluid into the intake? How much fluid is in the tranny?
You need to buy a Factory Service Manual (FSM) to figure out what is going on w/ your car, any car smoking like you describe has a serious problem. Is the car auto or stick? If it is auto, could it be sucking trans fluid into the intake? How much fluid is in the tranny?