LT4 New LT4 owner

[jcs44]

Hello folks,

Just coming on board as new LT4 owner (just sold my 95 LT1, 6M). I figure the 96 LT4 is the ultimate C4. I now have a black on black convertible with under 28K on the clock, and a hardtop. Has all options except suspension stuff. Also has nearly new Goodyear EMTs and a new battery. The only problems are that the horns don't work - I took them out and there is 12V at the connnector. Often when I start it up a "SYS" warning flashes 3 times in the digital display and then goes away. Any thoughts?

PS-what's the real HP on an LT4? Everything I read says they were underrated.

Thanks, John

 

[Tuna]

There are a few ZR1 guys around that may disagree with the "ultimate C4" comment.

The "SYS" light indicates an electrical problem some where - low voltage, and many other issues. Check out that new battery and the cables to start with - everytime this has come up on my car, it's meant the battery was ready to die so it may have something to do with the cables. There are others things to check and codes to pull but I'll let more knowledgable people jump in now.

As for LT4 horsepower - 350+ seems reasonable since many are putting 300 to the rear wheels (check out www.grandsportregistry.com/dyno.htm).

Good luck with the horns. I don't have a clue.

 

[Gman]

Welcome to the joys of LT4 ownership and the CAC! Wish I could help you with the horn problem. I haven't had to deal with that problem...yet :L

BTW, if you can't find an answer by doing a search you may want to pose this question in the C-4 tech forum. It's a general problem rather than LT-4 specific. Good luck!

 

[Gary04Z06]

Great choice!! Welcome to the club!

 

[froggy47]

Mine had a dead horn, maybe yours has 2. For $10 at PepBoys you can get a replacement horn & try it. Or $50 or so for oem. They are two different "notes" I think the right is F note, don't know on the left.

 

[B17Crew]

jcs44,
Congratulations on your LT4 vert, sounds like a great car to drive, top-down fun and the LT4 to motivate things along.

I had two driver side horns go on me (covered under warranty). Dealer told me that they had “shorted out.”

After the second horn offering up its spirit. I tried to figure out what could be shortening the horns life. I noticed that after I had washed my car, dried the exterior, and raised the hood to wipe down the engine compartment; water from the black plastic wheel shrouds would flow directly onto/ontop of the horn assembly.

This is only a theory, but I can’t help but wonder if over time, water doesn’t get in there and cause a little voodoo.

I have since taken precautions to protect the horns when I wash the car. So far, no problem for three or four years. Is this a sure fire solution? I doubt it, but I’ll try anything to increase the longevity of original C4 parts as OEM parts are becoming scarce for our cars.

B17Crew

 

[atmmac]

Did you know you can get airhorns for $20. I have them on my impala. Talk about fun to beep your horns!

-Andy

 

[jcs44]

Good thought. I'll have a look at that.

 

[froggy47]

I saw those on the shelf & was thinking about it. Just one more ahole on the freeway cuts me off & I'm gonna put the airhorns in!

 

[GS Diva]

John,

Welcome to the Corvette Action Center!! You made the very best choice of C4's!!:dance

Elaine

 

[96lt4conv]

Welcome to the LT4 world!

With engine not running - press the horn buttons on the wheel. When you push them you should here the relay closing, it "clicks" each time you push the buttons. The relay is located behind the knee bolster on the passenger side. If you do not here the relay "clicking" then it is the fuse or the relay. The only way to replace it is to pull the knee bolster out. I also have a conv. my horns did not work. When I checked the relay I found that some water had made it's way into the relay box (also contains interior light relay, fog light relay and fuel pump relay).

Scott

 

[jcs44]

Thanks for the tips. I can hear the horn relay click when I press either wheel button and I have checked for voltage at the horns plug when the buttons are pressed - it's there. All that leaves is the horns themselves. I pulled both off and sprayed the inside of one with WD40. After soaking for about a week, I banged the horn around a little and plugged it in - voila! It works again. Guess I'll try the same procedure on the other one. I think they get moisture in them and corrode the coil or diaphram and just lock up, or maybe just lack of use as this car spent a lot of time sitting.


JCS44

 

[Edmond]

Congrats on the LT4 and an awesome color combo! I always thought the LT4 seemed to be so underrated and forgotten. :eyerole

 

[Skant]

Stock LT4's typically develop 350-360 horsepower... quite a lot more than their 330hp official rating. Some totally stock LT4's have registered nearly 400hp.

I raced against a 2003 Z06 once in mine when my car was in stock trim... not quite as fast as him, but he only pulled on me by half a car length on the way to 60mph. On paper, according to the official specs, he should have walked away from me easily.

The LT4 was kept in the closet so as not to overshadow the C5's of the following year.

It's not quite as fast as the ZR1 in stock form, but it accepts most of the wide array of LT1 modifications and parts... so it's easier to add horses to it, and it's less expensive to maintain. Plus, the ZR1 is about 200lbs heavier so the differences in horsepower rating are somewhat mitigated by that. Plus the lighter car should handle a little better.

It is my opinion that the LT4, ZR1, and Z06 are all in roughly the same ballpark. All three are wonderful examples of the best the Corvette name has to offer... but achieved in slightly different ways.

 

[jcs44]

Thanks! That's good info and about what I expected.

John

 

[B17Crew]

It is my opinion that the LT4, ZR1, and Z06 are all in roughly the same ballpark. All three are wonderful examples of the best the Corvette name has to offer... but achieved in slightly different ways.

Well put...

B17Crew

 

[354RwHpLT4CE]

Congrats on your new CE!I know you will love it!Shannon

 

[89popalop]

new LT4 OWNER

i am a new LT4 owner.I would like to know about unpluging the 1st to 4th plug.should i or should i leave it alone. how hard is it to do can i do it myself. any help to this quistion would be a big help.if you did this is it working out for you thanks

 

[jcs44]

i am a new LT4 owner.I would like to know about unpluging the 1st to 4th plug.should i or should i leave it alone. how hard is it to do can i do it myself. any help to this quistion would be a big help.if you did this is it working out for you thanks

Do not just unplug it. That will disable it but will also set a code in the computer and put a warning on the dash. There are by-pass plugs available from places like Ecklers, Mid-America, and ebay. These plugs show the correct resistance to the computer and avoid the warnings. There are different models depending on the year of the vehicle. They also seal the ends of the old plugs from the weather. The shift 1 to 4 light will still come on, but the system is disabled. It's easy to do, but you need to jack it up and crawl under there on the drivers side - do this safely, with jack stands. It's handy, just do it right. John

 

[froggy47]

I would say 9 out of 10 owners unplug it. It's on the driver side of the tranny, it's easy (if you can get to it, probably need to get on ramps or a lift).



Mine is just unplugged, no codes set, no warnings on the DIC. The 1-4 shift light DOES still come on - ignore it.