1991 Fuel Injector Problems
Thread Starter
Heel & Toe
Joined: Sep 2005
Posts: 18
Likes: 0
1991 Fuel Injector Problems
My 1991 is running rough at idle where it used to be smooth as glass. I changed the plugs and wires, even changed out the C02 sensor. Now I'm told that the E10 fuel that is being sold has caused my fuel injectors to go south in a big way. Anybody else having problems with original injectors going bad because of the new fuel? Thanks for your help or input in advance.
Burning Brakes
Joined: Nov 2008
Posts: 995
Likes: 1
From: Naples Campania
The stock Multec injectors don't like ethanol at all. They aren't bad injectors, they just weren't designed for this type of fuel. If they are stock injectors, I would vote that it is part of your problem.
Talk to Jon at FIC. You will find something that you will like. I haven't heard a single bad thing here about FIC.
Talk to Jon at FIC. You will find something that you will like. I haven't heard a single bad thing here about FIC.
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
The stock Multec injectors don't like ethanol at all. They aren't bad injectors, they just weren't designed for this type of fuel. If they are stock injectors, I would vote that it is part of your problem.
Talk to Jon at FIC. You will find something that you will like. I haven't heard a single bad thing here about FIC.
Talk to Jon at FIC. You will find something that you will like. I haven't heard a single bad thing here about FIC.
Fuel Injector Connection, LLC
4966 Wade Valley Way
Cumming, GA 30040
Tel: 770-888-1662
Jon at FIC http://fuelinjectorconnection.com/shop/
SEND FICINJECTORS A PM HERE
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Team Owner
Joined: Jul 2004
Posts: 28,369
Likes: 3,258
From: Hartford WI
I believe all it will tell you is resistance. Even if everything is clogged up beyond what the ECM can adjust to, it might still ohm out fine. I haven't had to ohm check an injector. Ever 3 or 4 years, I just send them off for testing and cleaning to Jon or RC Engineering, etc, etc. Let them check it out and if it comes out good, fine. If not, they fix. Either way, it should be a PM item for every few years to have it cleaned and tested. Way more productive than an ohm test
Team Owner
Joined: Jul 2004
Posts: 28,369
Likes: 3,258
From: Hartford WI
I wouldn't. I'd postpone the shop visit for a couple of weeks while you send your injectors off. I have been to quite a few shops and when they suspect something that has some link to the injectors, they want to replace them and not test them. I don't even think I have seen a shop besides Lingenfelters that has an injector flow bench.
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Burning Brakes
Joined: Apr 2009
Posts: 877
Likes: 0
From: Broken Arrow Oklahoma
I believe all it will tell you is resistance. Even if everything is clogged up beyond what the ECM can adjust to, it might still ohm out fine. I haven't had to ohm check an injector. Ever 3 or 4 years, I just send them off for testing and cleaning to Jon or RC Engineering, etc, etc. Let them check it out and if it comes out good, fine. If not, they fix. Either way, it should be a PM item for every few years to have it cleaned and tested. Way more productive than an ohm test
Burning Brakes
Joined: Nov 2008
Posts: 995
Likes: 1
From: Naples Campania
I had a miss when I bought my car and suspected the injectors as they were the original ones. I check the ohms as a quick way to determine if they were shorted because of the fuel we use. Two of them read 5.6 4.5 the rest were 16.2, I called Jon and ordered a set of his injectors. Fixed the problem.
The injectors can be rebuilt for cheap. However, I would go with the Bosch III design. They are simply better built and the atomization is a hell of a lot better. You will get a much better fuel burn and therefor, more power. I just ordered a set (24lb since I dropped a ZZ4), but you should go with the 22 lb injectors since it's stock. If you put even 24 lb in there, you'll need a tune to run properly. I learned the hard way and now my car is RICH. With new injectors, I can clean the carbon off the exhaust and be back to a nice clean system.
Team Owner
Joined: Jul 2004
Posts: 28,369
Likes: 3,258
From: Hartford WI
I had a miss when I bought my car and suspected the injectors as they were the original ones. I check the ohms as a quick way to determine if they were shorted because of the fuel we use. Two of them read 5.6 4.5 the rest were 16.2, I called Jon and ordered a set of his injectors. Fixed the problem.
