1989 l98

[JoMo5505]

Recently bought 1989 roadster w/Greenwood pkg.It has 15000 miles.Looks great.Motor is the famous L98? hooked to 4 speed auto.This vette runs and handles great then came the fuel injector problem!!Turns out 3 were replaced by previous owner[original] and needed 3 more,so we made it 5 which= 8 by the dealer I bought it from.My question is what do I and should I work the motor for more H.P.and should all injectors be replaced? 2nd owner JoMo55

 

[BADDUCK]

Once they start going bad you should replace them all with the same exact type. From your post it's not clear you have done that. Stock injectors were originally 22 lb/hr Multechs FWIW.

 

[WRECKER88]

Call Jon at FIC he will get you what you need. I just replaced my Injectors today and the car runs like it did 21 years ago.

Fuel Injector Connection

 

[Edmond]

Once they start going bad you should replace them all with the same exact type. From your post it's not clear you have done that. Stock injectors were originally 22 lb/hr Multechs FWIW.

Definitely true. It's the same work to take the fuel rail off and the car will be down for pretty much the same amount of time.

Lots of guys go with the 24 lb/hr injectors now, I think the OEM were Bosch, though. Lots of guys go with the Ford "pink top" injectors.

The L98, due to the runner length, was never really a high HP machine, it provided incredible torque, 340 lbs @ 3200 RPM, IIRC, which makes it great from stop light to stop light.

The weakness in the L98 cars was also the exhaust system. If you replaced the exhaust system headers to mufflers, I would expect a power increase of 25+ HP. I believe the stock mufflers also only flowed out of one outlet. The stock exhaust manifolds also hinder flow with the pup cats. Headers would increase flow as well as cut weight.

 

[JoMo5505]

Once they start going bad you should replace them all with the same exact type. From your post it's not clear you have done that. Stock injectors were originally 22 lb/hr Multechs FWIW.

From what I am told 1st owner replaced 3 injectors!remember car only had 14,300 when I got it.then my guy tells me 3 more are bad then I sugg.to replace the 2 remaining also,which=5 that we replace..How often do they go bad or is it from lack of use.(wont happen from now on)or dirty gas tank? also thanx for the replies!!!!

 

[BADDUCK]

They can get clogged, short out, be damaged by fuel additives, deteriorate with age or millage. My advice, replace the other 5 with similar type injectors to match the first 3.

 

[FForward]

The 89 Vette's used Multitec injectors and they are junk. They have the coil in the fuel stream, so the use of fuel cleaner destroys them. If you have a problem with one of them, change them all out. Get a set of Bosch Gen 111 from Jon Banner at FIC. You'll be surprised at the difference they make.

I had problems on my 89 with injectors. Car ran fine, went into store for 5 mins, came out and it wouldn't start. After trying for some time to start it, called the tow truck. When it got to the shop and off the truck, it started up right away. Injectors were checked and a few were bad. A bad or shorted injector will shut down the system. I changed them all out with the Gen 111 from Jon and had no more problems. I also picked up better performance and the car ran better than ever before. Anyone that still have Multitec's installed is going to have problems sooner or later. If a dealer installed or replaced only a few, they might have been Multitec's also. Your best bet is to get rid of them all and use Bosch Gen 111. Talk to Jon at FIC, he is the man to go too for injectors.