Where to Start - Idle Problems....
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The gas tank filler neck seal wil come off and go on thru the gass fill door. There is no need to drop tank.
What do you expect the car to idle at? You indicated that you had a buddy push in the throttle unit it reached 700-800 RPM. What engine and transmission do you have? The owners manual for my 70 indicates idle speeds of from 700 to 1000 for manual trans cars. Your idle should not be set below 700
What do you expect the car to idle at? You indicated that you had a buddy push in the throttle unit it reached 700-800 RPM. What engine and transmission do you have? The owners manual for my 70 indicates idle speeds of from 700 to 1000 for manual trans cars. Your idle should not be set below 700
I have the 350 with the manual.
I'll look into the idle requirements for mine once I get the books i ordered. It could be an idle screw adjustment but my instincts tell me it's more complicated than that... (ie. the water issue)
Thanks,
Ryan
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You can rebuild your q jet after you get your book.
In the interim, syphon as much gas out of the tank as possible, put in a water removal product and some fresh gas. It will cure it for now.
As suggested earlier, plug all the vacuum ports on carb and manifold except for pcv system and test and adjust the carb for idle. Then reconnect one by one and look for rough idle. After all is reconnected/rplaced then readjust your carb.
If you are idling at 700 or 800 now, the carb isn't that bad, but a self rebuild is cheap and worth it.
If you have ordered a new tank boot, just remove the old one for now to prevent any new water entering the tank.
In the interim, syphon as much gas out of the tank as possible, put in a water removal product and some fresh gas. It will cure it for now.
As suggested earlier, plug all the vacuum ports on carb and manifold except for pcv system and test and adjust the carb for idle. Then reconnect one by one and look for rough idle. After all is reconnected/rplaced then readjust your carb.
If you are idling at 700 or 800 now, the carb isn't that bad, but a self rebuild is cheap and worth it.
If you have ordered a new tank boot, just remove the old one for now to prevent any new water entering the tank.
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Update
Okay, a little update. While wait on the books and seals that I ordered.
I started the vette up today and at first it was hesitant. It needed a few pumps of the pedal and a couple 10 second cranking sessions to start. Once it fired I didn't touch the pedal. It then idled pretty decent for a while... 5 to 8 minutes.... I then got back in and the instant that i blipped (slight tap then off the pedal) it just dropped and died out. Upon restart I couldn't get it to stay idling. Any additional thoughts?
ps. I'm going to start a new thread on my brakes issue... it never ends
I started the vette up today and at first it was hesitant. It needed a few pumps of the pedal and a couple 10 second cranking sessions to start. Once it fired I didn't touch the pedal. It then idled pretty decent for a while... 5 to 8 minutes.... I then got back in and the instant that i blipped (slight tap then off the pedal) it just dropped and died out. Upon restart I couldn't get it to stay idling. Any additional thoughts?
ps. I'm going to start a new thread on my brakes issue... it never ends
Le Mans Master
Joined: Jan 2006
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From: Boca Raton Florida
your choke is working, thats why it ran well at first, then you bliped the throttle and the choke opened and it died. That says look at the idle screw on the drivers side of the carb, give it a turn in and try it again. Look at the tip of the screw, make sure it is contacting the stop on the throttle plate idle stop lever.
Drifting
Joined: Sep 2002
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From: South Florida
I didn't see this flat round gasket with the bolt holes that you mentioned for the filler neck on Ecklers. I will look more and check other sites to find it, but if you know who carries it or if you have a link then that would be awesome.
Good info on the vac items. I will follow that procedure and see what I can find out. Thanks!
Good info on the vac items. I will follow that procedure and see what I can find out. Thanks!
http://www.tld-corvette.com/
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your choke is working, thats why it ran well at first, then you bliped the throttle and the choke opened and it died. That says look at the idle screw on the drivers side of the carb, give it a turn in and try it again. Look at the tip of the screw, make sure it is contacting the stop on the throttle plate idle stop lever.
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I think I got mine from Last Detail. I replaced this weekend. search for gas tank gasket. 3rd page I think.
http://www.tld-corvette.com/
http://www.tld-corvette.com/
http://www.zip-products.com/Zip/prod...26C546E566AC4A
I was told that I can take off the big rubber boot and the filler neck to replace this seal without dropping the tank. I hope this is the case. I looked at the big rubber boot and it looks like it will be a pain to pull out of there.
Racer
Joined: Jul 2006
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From: S.E. Michigan
St. Jude Donor '07-'08-'09-'10
Not sure what that means? Lurk is the name of the icon? I assume it's intented to give me grief or laugh at a dumb question.
Anyways, I ordered a whole kit to replace vac lines and heater hose from Ecklers and hope that should provide me with all that I need to take the variable out of the equation.
Anyways, I ordered a whole kit to replace vac lines and heater hose from Ecklers and hope that should provide me with all that I need to take the variable out of the equation.
Drifting
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From: Edinburgh
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Last edited by VTcivil; Jul 13, 2007 at 09:38 AM. Reason: spelling
Melting Slicks
Joined: Oct 2005
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From: Redruth Cornwall
You said that this has been a problem from when you first got the car 1 1/2 years ago...thats along time to let water do damage if it is water related.
If you can start the car from cold and it idles fine, then as has been said before the choke and the fast idle are working.
As soon as you blip the throttle you will come off the fast idle cam as I understand and will then be running on your normal idle circuit.
Have you tried simply adjusting the idle mixture screws and the curb idle speed screw? IIRC from what Lars has said a good place to start is to slowly and gently wind the 2 idle mixture screws in until they bottom, then back them out 2 12/2 turns. See how that works and adjust from there.
If when you blip the throttle and it goes to die, can you keep it running by giving it gas?
If you can start the car from cold and it idles fine, then as has been said before the choke and the fast idle are working.
As soon as you blip the throttle you will come off the fast idle cam as I understand and will then be running on your normal idle circuit.
Have you tried simply adjusting the idle mixture screws and the curb idle speed screw? IIRC from what Lars has said a good place to start is to slowly and gently wind the 2 idle mixture screws in until they bottom, then back them out 2 12/2 turns. See how that works and adjust from there.
If when you blip the throttle and it goes to die, can you keep it running by giving it gas?
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Good advice on that idle screw thing. I will look into that on Monday night since I am out of town this weekend.
Thanks!
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Update:
Now that I got my brakes working I can now finish diagnosing my idle issues.
I followed the reccomendation of adjusting the idle screw. I did this and the vette now idles when warmed up and did not stall while idling in the garage.
I just took if for a spin and it seemed to be fine for a couple miles and didn't stall. After a couple miles it died at a couple stop signs upon stopping. It has been doing this for a while now. After restarting those couple times, I had to blip the throttle at the next few stop signs.
By the time I got back to my street is was now idling very high and not stalling when stopping. It seems like something changed and it was idling too high now and that the idle screw adjusments I made just masked the initial problem.
Seems to me there is more to this than the idle screw since it ended up idling high after a bit of driving.
Any ideas guys?
I'm to the point I want to rip this carb off and send it out for a complete redo or just get a new Qjet from Zip or Ecklers.
I'm open to all suggestions... Thank you in advance!
-Ryan
Now that I got my brakes working I can now finish diagnosing my idle issues.
I followed the reccomendation of adjusting the idle screw. I did this and the vette now idles when warmed up and did not stall while idling in the garage.
I just took if for a spin and it seemed to be fine for a couple miles and didn't stall. After a couple miles it died at a couple stop signs upon stopping. It has been doing this for a while now. After restarting those couple times, I had to blip the throttle at the next few stop signs.
By the time I got back to my street is was now idling very high and not stalling when stopping. It seems like something changed and it was idling too high now and that the idle screw adjusments I made just masked the initial problem.
Seems to me there is more to this than the idle screw since it ended up idling high after a bit of driving.
Any ideas guys?
I'm to the point I want to rip this carb off and send it out for a complete redo or just get a new Qjet from Zip or Ecklers.
I'm open to all suggestions... Thank you in advance!
-Ryan
Last edited by VTcivil; Oct 22, 2007 at 11:30 PM.
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Also note that the only screw I adjusted was on the driver side of the carb that adjusts the stop for the throttle. I haven't messed with the mixture screws since I don't even know where they are yet. I did buy a few carb and Rochester books that I plan to dive into very soon.
Intermediate
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From: dallas ga
VT, On the Q-jet you have two idle mixture screws at the front of the carb down low(in the throttle body).Turn those screws in until they lightly seat, then turn them each out 2 and 1/2 turns this will get you close. Get a vacuum guage and connect to the port in the intake behind the carb(intake vacuum) adjust the screws for maximum vacuum.Also check your dwell(points) and timing.Hope this was a help for you.