1989 fuel injectors bad?
Thread Starter
Instructor
Joined: Mar 2008
Posts: 117
Likes: 0
From: Wichita Kansas
1989 fuel injectors bad?
I took my 1989(automatic transmission) to a mechanic recently because it is running very poorly. Has been surging for some time now and when i first start it up, will start but unless I keep foot on the gas, will die. After a few minutes of high reving it will stay running but sounds terrible. When i back out of driveway and put it in drive, hesitates like is going to die, i pump gas pedal and we take off. at the stop sign, i have to put it in neutral as i roll up to sign or will try and die. then put in drive, push gas and will go but missing and sounds awful. The mechanic says I have 5 out of 8 fuel injectors that are bad. Does this sound right? Would I have even been able to drive it up there with 5 out of 8 "bad"?
Keep in mind Im a female.
Keep in mind Im a female.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 411
From: WV
89 Corvettes Multec injectors are not ethenol compliant so thats more than likely your problem. Most of use on this forum have had to replace our injectors on our 89-91 Corvettes already, myself included .Its not if these Multec injectors will fail, its when... The best way of fixing this is to get in touch with Jon at FIC fuel Injectors and order a rebuilt set from him, on this site he's the go to guy for injectors and won't do you wrong..If you can put them in yourself thats the cheapest way to go but if not find a garage you trust.. WW
Call and ask for Jon, he will take care of you..WW
http://www.fuelinjectorconnection.co...&productId=134
Call and ask for Jon, he will take care of you..WW
http://www.fuelinjectorconnection.co...&productId=134
Last edited by WW7; Mar 30, 2010 at 08:36 PM.
Melting Slicks
Joined: Dec 2009
Posts: 2,226
Likes: 283
Hey vetdrem, do you have a list of what the mechanic checked? I'm wondering if they'd checked fuel pressure & leak down, injector pulse, state of tune up parts, & scan it for codes & live data. You can never ask too many questions when your paying for auto repairs.
Pro
Joined: Oct 2009
Posts: 679
Likes: 0
From: vero beach florida
5 of 8 failing at once, is almost to much to believe. Did it start running bad all at once or gradually over time?
How did he determine they were bad, did he OHM them?
OHM meter measures resistance in wires and other electrical connections.
OHM readings above 13 is good and below is bad.
When was the last tuneup?
Did anybody do anything to the engine just before it started running bad?
How did he determine they were bad, did he OHM them?
OHM meter measures resistance in wires and other electrical connections.
OHM readings above 13 is good and below is bad.
When was the last tuneup?
Did anybody do anything to the engine just before it started running bad?
Racer
Joined: Dec 2009
Posts: 298
Likes: 0
From: Reno NV
My 89 was doing the same thing. I just replaced my injectors to bosch 3s from Jon @ FIC. WAAAAAYYY better running car now. I had at least 2 or 3 injectors that was bad. For about $200 bucks you cant beat FIC's prices. Not to tough to install.
Instructor
Joined: Mar 2008
Posts: 148
Likes: 0
From: Rindge NH
5 out of 8 injectors going bad at once on an '89 is very believable. As WW stated, the Multecs are not ethanol compatible. Just the little used in pump gas not designated as E85 is enough to ruin these injectors.
Easiest check is the "ohm check". Pull the plug off the injector, measure across the pins with a digital ohm meter - less than 12-14 ohms, replace them before you ruin an ECM.
I dealt with Jon @ FIC when I needed injectors. Great pricing and you'll be hard pressed to find better customer service anywhere. Some shops aren't willing to install customer provided parts - ask yours, then call Jon.
If your shop won't install supplied parts, are there any forum members close to you who'd do the install?
Easiest check is the "ohm check". Pull the plug off the injector, measure across the pins with a digital ohm meter - less than 12-14 ohms, replace them before you ruin an ECM.
I dealt with Jon @ FIC when I needed injectors. Great pricing and you'll be hard pressed to find better customer service anywhere. Some shops aren't willing to install customer provided parts - ask yours, then call Jon.
If your shop won't install supplied parts, are there any forum members close to you who'd do the install?
Thread Starter
Instructor
Joined: Mar 2008
Posts: 117
Likes: 0
From: Wichita Kansas
Very true. I dont have a list at this time but will call him and get one and post it on here. I remember him checking the pressure with a fuel pressure gauge and it being fine. Seems like he also said I needed to replace my spark plugs. I will get a list as soon as i can.
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Thread Starter
Instructor
Joined: Mar 2008
Posts: 117
Likes: 0
From: Wichita Kansas
5 out of 8 injectors going bad at once on an '89 is very believable. As WW stated, the Multecs are not ethanol compatible. Just the little used in pump gas not designated as E85 is enough to ruin these injectors.
Easiest check is the "ohm check". Pull the plug off the injector, measure across the pins with a digital ohm meter - less than 12-14 ohms, replace them before you ruin an ECM.
I dealt with Jon @ FIC when I needed injectors. Great pricing and you'll be hard pressed to find better customer service anywhere. Some shops aren't willing to install customer provided parts - ask yours, then call Jon.
If your shop won't install supplied parts, are there any forum members close to you who'd do the install?
Easiest check is the "ohm check". Pull the plug off the injector, measure across the pins with a digital ohm meter - less than 12-14 ohms, replace them before you ruin an ECM.
I dealt with Jon @ FIC when I needed injectors. Great pricing and you'll be hard pressed to find better customer service anywhere. Some shops aren't willing to install customer provided parts - ask yours, then call Jon.
If your shop won't install supplied parts, are there any forum members close to you who'd do the install?
Pro
Joined: Oct 2009
Posts: 679
Likes: 0
From: vero beach florida
5 out of 8 injectors going bad at once on an '89 is very believable. As WW stated, the Multecs are not ethanol compatible. Just the little used in pump gas not designated as E85 is enough to ruin these injectors.
Easiest check is the "ohm check". Pull the plug off the injector, measure across the pins with a digital ohm meter - less than 12-14 ohms, replace them before you ruin an ECM.
I dealt with Jon @ FIC when I needed injectors. Great pricing and you'll be hard pressed to find better customer service anywhere. Some shops aren't willing to install customer provided parts - ask yours, then call Jon.
If your shop won't install supplied parts, are there any forum members close to you who'd do the install?
Easiest check is the "ohm check". Pull the plug off the injector, measure across the pins with a digital ohm meter - less than 12-14 ohms, replace them before you ruin an ECM.
I dealt with Jon @ FIC when I needed injectors. Great pricing and you'll be hard pressed to find better customer service anywhere. Some shops aren't willing to install customer provided parts - ask yours, then call Jon.
If your shop won't install supplied parts, are there any forum members close to you who'd do the install?
My van has Multitecs and is still running strong and my 92 has them and it runs great, so until you have proof, I am not going to believe you.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Fuel Delivery is based on the Coolant Temp signal so hopefully that was checked. On my '89, it suddenly started toggling somewhere between 220 and 235, so cold starts were difficult if not impossible. Amazingly, a few others experienced same and troubleshooting led to bad ECM's. Whether or not we all had the same rebuild (I'm on my 4th or 5th with 3 replaced under the original warranty) was something I didn't explore, but hooking up a scanner - if you haven't - might not be a bad idea.
Racer
Joined: Jan 2007
Posts: 322
Likes: 0
From: Chapin South Carolina
Ethanol is not bad really for the injectors. But hydrous ethanol used to mix with gasoline is bad because "Hydrous ethanol (about 95% ethanol and 5% water) can be used as fuel in more than 90% of new cars sold in the country. "; source: http://en.wikipedia.org/wiki/Ethanol.
It is the 5% water that causes the problems. Most older injectors where not made of stainless steel because at the time it was not needed. Now that no one sells non-ethanol gas around me, I am using the 10-15% Ethanol blends. The 5% water of the 10% blend, which isn't a whole lot, will at some point cause corrosion in your injectors and that corrosion will clog your injectors at some point. If you have injectors with stainless steel cores then you will not experience this problem, which may be why you have not ran into the problem.
It is the 5% water that causes the problems. Most older injectors where not made of stainless steel because at the time it was not needed. Now that no one sells non-ethanol gas around me, I am using the 10-15% Ethanol blends. The 5% water of the 10% blend, which isn't a whole lot, will at some point cause corrosion in your injectors and that corrosion will clog your injectors at some point. If you have injectors with stainless steel cores then you will not experience this problem, which may be why you have not ran into the problem.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 411
From: WV
Ethanol is not bad really for the injectors. But hydrous ethanol used to mix with gasoline is bad because "Hydrous ethanol (about 95% ethanol and 5% water) can be used as fuel in more than 90% of new cars sold in the country. "; source: http://en.wikipedia.org/wiki/Ethanol.
It is the 5% water that causes the problems. Most older injectors where not made of stainless steel because at the time it was not needed. Now that no one sells non-ethanol gas around me, I am using the 10-15% Ethanol blends. The 5% water of the 10% blend, which isn't a whole lot, will at some point cause corrosion in your injectors and that corrosion will clog your injectors at some point. If you have injectors with stainless steel cores then you will not experience this problem, which may be why you have not ran into the problem.
It is the 5% water that causes the problems. Most older injectors where not made of stainless steel because at the time it was not needed. Now that no one sells non-ethanol gas around me, I am using the 10-15% Ethanol blends. The 5% water of the 10% blend, which isn't a whole lot, will at some point cause corrosion in your injectors and that corrosion will clog your injectors at some point. If you have injectors with stainless steel cores then you will not experience this problem, which may be why you have not ran into the problem.
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Last edited by WW7; Mar 31, 2010 at 09:01 PM.
Le Mans Master
Joined: Feb 1999
Posts: 6,470
Likes: 2
From: levittown pa. usa Even a bad day with my `Vette, is better than a good day at work
St. Jude Donor '10
about the technology part. I`m running Ford 5.0 "pink top" injectors in my `87 for the last 5 years. Runs great. 
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 411
From: WV
If ethonal was so bad for Multitecs, 100% of Chevy car and trucks w/them would have gone bad that had them and I do not see that.
My van has Multitecs and is still running strong and my 92 has them and it runs great, so until you have proof, I am not going to believe you.
My van has Multitecs and is still running strong and my 92 has them and it runs great, so until you have proof, I am not going to believe you.
Last edited by WW7; Apr 1, 2010 at 10:33 AM.
Pro
Joined: Oct 2009
Posts: 679
Likes: 0
From: vero beach florida
All multecs don't have this problem, I believe its just the years from 89 to 91. There are other years out there that never see any problems.If you watch the FIC videos at the top of the tech section you will learn alot from someone that knows about injectors, then you don't have to (Believe Us)...WW
Had a 89 w/179k miles and my 90 van had over 210k miles and still going on multitecs, if this is such a problem, GM would have put out atleast a TSB on them.
Not doubting them going bad, they are 20+ years old, heck if I replace plugs w 10-15k miles on the car, it will run better, that is not proof, I want to see where someone ran them for x miles and they broke down because of ethonal.
I was on the f-body forum and do not see near the beefs w/multitec's and they use the same injector.
Instructor
Joined: Mar 2008
Posts: 148
Likes: 0
From: Rindge NH
I had a set of stock replacement Multecs go bad in less than 6 months. 5 of 8. There is a different injector GM uses for warranty work. Those are currently in my car and running fine.
The Corvette injector was not used in the van lines - just F and Y bodies. '92 Corvettes used a different injector - first year for LT1.
My '97 LT1 Trans Am has no injector issues. I can't speak for the 3rd gen CamaroBirds - I don't have any experience with them.
1992 is not a suspect year for Corvettes. Neither is '88, I've looked at those, different injector, as are the '90 ZR1 injectors.
The stock '89-'91 Multecs are that bad....
The Corvette injector was not used in the van lines - just F and Y bodies. '92 Corvettes used a different injector - first year for LT1.
My '97 LT1 Trans Am has no injector issues. I can't speak for the 3rd gen CamaroBirds - I don't have any experience with them.
1992 is not a suspect year for Corvettes. Neither is '88, I've looked at those, different injector, as are the '90 ZR1 injectors.
The stock '89-'91 Multecs are that bad....