VirginiaVette78

Hey all, it's me again, the fella who keeps learning the hard way....
So I was at a buddy's house so we could mock up some custom brackets for my cheapo sidepipes... got a gameplan, helped him bleed some truck brakes, and off I went.

I backed out of his driveway - shifted into first - and started on my way..
First, second, brake for a stopsign.. but it didnt leave second and had to stomp brakes to get it to stop.. I live a block away so I decided I was gonna limp it home...
Let off the brake and damn near spin the tires without me hitting the gas..
Another stop sign and same thing.. I shift into N to see if it will help - nothing, I throw it back into 3 and cross the street into my driveway, threw into N so I could coast into my garage without going through it..
Checked my lockdown cable, its attached and functioning as far as I can tell (is there a way to test it?)
It was very very low on trans fluid..
I'm hoping that it's as simple as add some fluid and all will be right. I have some on order (nobody carries dexron III near me)..
Thoughts and opinions??


Also, if anyone is running sidepipes with long tube headers - can you send me some underside pics please? Thanks all!!

VirginiaVette78

Also forgot to mention that I'm sitting at a constant 4500 rpm so I'm really not trying to start it much!

bazza77

I hope your clutches are ok , very easy to burn them out !!!

Bikespace

You are missing a third pedal to the left of the brake pedal.

But seriously, check that your throttle return springs are intact, and function check them with the air cleaner off.

VirginiaVette78

Yeah, me too!!

Ha, I couldn't agree more.. but the deal with the wife was that if I bought a corvette, it had to be an automatic so she could drive it....
I'll function check everything tonight when i get home.. found a nice leak from the transmission pan last night that explains where my fluid went.. i just put a new gasket on the darned thing too!

Kacyc3

well thats why it spun the tires without touching the gas...check to make sure all linkages are moving correctly and nothing is stuck wide open.

VirginiaVette78

10-4. Should I be looking anywhere other than where the trans/accel connect to carb?

VirginiaVette78

Update: I checked the cables and dont see any binding anywhere. Trans fluid is good and wasn't as bad as i thought to begin with (a bit low but not bad enough to make a difference - checking when its light out helps!!)
I dont think it's a transmission issue now because it's super high rpm when the car is in park, N, or in gear..
I cant imagine it being a throttle plate issue because it drove fine over to his house..

Could a vacuum cause that high of an RPM jump?
I'm at a loss here.

28buick

Try disconnecting the throttle cable and starting it. if it idles normal its in your linkage.

shenango

If your carb still has the AC idle solenoid make sure it is not causing the problem. This solenoid will cause all kinds of rpm problems if not operating correctly.
Jerry

VirginiaVette78

no go on that - no binding in linkage. good thought though!

I do not have one. I tried the old "plastic bag to block air" method yesterday, and it worked - when i blocked air from getting into the carb, it starved out. So its gotta be vac somewhere (i think)

bmans vette

If the engine dies when you block the air into the carb, that means you don't have a leak. If it continued to run, THEN you would have leak.
Think about it for sec and it will make sense.
Good luck finding the cause.......

stumpshot

If you have an automatic choke make sure the choke high idle cam isn't sticking and holding the throttle open.

derekderek

78? q-jet? back barrels and air flapper on top closed? hrd to get 4500 rpms without being able to see the gap-hole that is acting as an IAC. brake vacuum hose? OK, idle air uncontrolled...

VirginiaVette78

Yep, makes perfect sense! Thanks!

So part of my issue was the choke - everyone kept telling me to check it, and i did and thought it was OK - but once i garnered the courage to actually hit the throttle and watch what the choke was doing, thats when i noticed what was happening.. the choke plate was opening, but not quite to 90 degrees.. there was not MUCH left to open, but enough to cause some of the high idle.. still working on whats causing the rest though

No longer running the Q-jet.. running an edelbrock performer intake with a Holley 650 600 cfm single intake carb.