Acceleration problems...HELP! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Cal69Chevy · 03-22-2002, 04:00 PM

I have a '69 with a crate 350 with not more than 5,000 miles. It has the original Qjet and a TurboTrans 400. It's a daily driver and has been very dependable and smooth running. The trans shifts smooth and the engine is strong.

Just yesterday it started to hesitate off idle. It sounds like the engine sputters off idle and then finally kicks in. However, in neutral and park I can rev it slow or quicly off idle and it runs fine (no sputtering).

What are some of the possibilities and how do I determine which of these possibilities is the likely the cause?

Thanks in advance for any help.

Ken

67Blacksheep · 03-22-2002, 04:55 PM

Cal 69-
I'm in a similiar boat. Strange animals when your actually trying to move, huh? I have a Holley 750 on mine. I have pretty much narrowed it down to the power valve. For yours, you could be looking at a minor carb problem in the transition between idle and acceleration. Have you tried re-building the carb? Or running a high test gas? I once got some really poor pump gas and it caused havock until I ran it out. Good Luck!

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Gordo · 03-22-2002, 05:07 PM

Take a look at the accelerator pump,,,should see a nice squirt in the primaries when you move to WOT (engine off please), if not, rebuild time. If you have points (check dwell) and/or HEI check your advance also.

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1971 C10 swb stepside 350/700R4/3.73posi
Killingworth, Connecticut

Longhorn Man · 03-22-2002, 05:14 PM

Also good indication of a plug starting to fowl, or a plug wire that got burned and is shorting out.

------------------
'69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man
I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it.
Need to pick up the one ton Longhorn with a PONTIAC 350/350soon.
Thanks every one!

Check out The Longhorn Webite.
If you need a pic posted, E-mail me at longhornmail@yahoo.com
Andy, in Columbus Ohio

Cal69Chevy · 03-22-2002, 07:08 PM

So these suggestions would still apply even if it doesn't happen in park/neutal? I can go from idle to 3000 RPM's slow or quick and it doesn't stumble...only seems to stumble when in gear.

bigjimzlll · 03-22-2002, 08:38 PM

do you have a vacuum gauge? sounds like a carb stumble or advance prob..a vacuum gauge can help narrow it down.

Gordo · 03-22-2002, 09:06 PM

10-4

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1971 C10 swb stepside 350/700R4/3.73posi
Killingworth, Connecticut

03-22-2002, 04:00 PM	#1
Cal69Chevy Registered User Join Date: Nov 2001 Location: SoCal Posts: 136	Acceleration problems...HELP! I have a '69 with a crate 350 with not more than 5,000 miles. It has the original Qjet and a TurboTrans 400. It's a daily driver and has been very dependable and smooth running. The trans shifts smooth and the engine is strong. Just yesterday it started to hesitate off idle. It sounds like the engine sputters off idle and then finally kicks in. However, in neutral and park I can rev it slow or quicly off idle and it runs fine (no sputtering). What are some of the possibilities and how do I determine which of these possibilities is the likely the cause? Thanks in advance for any help. Ken __________________ '69 Chevy, 4X4-SB 350 TBI-TH350 Trans-205 Transfer Case-Dana 44 Front-14 Bolt Rear-Front Disc Brakes-Factory A/C-P/S Ken's '69 Page

03-22-2002, 04:55 PM	#2
67Blacksheep Registered User Join Date: Mar 2002 Location: Ohio Posts: 135	Cal 69- I'm in a similiar boat. Strange animals when your actually trying to move, huh? I have a Holley 750 on mine. I have pretty much narrowed it down to the power valve. For yours, you could be looking at a minor carb problem in the transition between idle and acceleration. Have you tried re-building the carb? Or running a high test gas? I once got some really poor pump gas and it caused havock until I ran it out. Good Luck! ------------------ __________________ '94 GMC Seirra Ext. Cab '67 Formula Firebird '89 GSX-R 750

03-22-2002, 05:07 PM	#3
Gordo Registered User Join Date: Jan 2001 Location: Killingworth, CT. USA Posts: 3,378	Take a look at the accelerator pump,,,should see a nice squirt in the primaries when you move to WOT (engine off please), if not, rebuild time. If you have points (check dwell) and/or HEI check your advance also. ------------------ 1971 C10 swb stepside 350/700R4/3.73posi Killingworth, Connecticut __________________ 1971 C10 swb stepside 350/700R4/3.73posi (retired as of 4/22/03) 1998 S10 short bed 2002 S10 Blazer 1942 Oldsmobile 1958 Massey Harris Pony 1951 Wife Killingworth, Connecticut May those who love us, love us, any of those who do not love us, may God turn their hearts. And if God is unable to turn their hearts, may he turn their ankles so we may know them by their limping. A man who works with his hands is a laborer; a man who works with his hands and his brain is a craftsman; but a man who works with his hands and his brain and his heart is an artist.

03-22-2002, 07:08 PM	#5
Cal69Chevy Registered User Join Date: Nov 2001 Location: SoCal Posts: 136	So these suggestions would still apply even if it doesn't happen in park/neutal? I can go from idle to 3000 RPM's slow or quick and it doesn't stumble...only seems to stumble when in gear. __________________ '69 Chevy, 4X4-SB 350 TBI-TH350 Trans-205 Transfer Case-Dana 44 Front-14 Bolt Rear-Front Disc Brakes-Factory A/C-P/S Ken's '69 Page

03-22-2002, 08:38 PM	#6
bigjimzlll Senior Member Join Date: Dec 2001 Location: Redding,CA...USA Posts: 4,736	do you have a vacuum gauge? sounds like a carb stumble or advance prob..a vacuum gauge can help narrow it down. __________________ It's called "drag racing" if they called it "tic..tic..WHAM!..BANG! F*&K!!!", they'd have to keep the magazines under the counter with the other men's publications click the clicky to join the site.... http://67-72chevytrucks.com/vboard/payments.php 67 lwb..first hotrod in 25 years..540 best ET is 9.45 @ 141.44 Anderson,CA

03-22-2002, 05:14 PM	#4
Longhorn Man its all about the +6 inches Join Date: Jan 2001 Location: Hilliard Ohio Posts: 2,693	Also good indication of a plug starting to fowl, or a plug wire that got burned and is shorting out. ------------------ '69 G.M.C. 350/350. Trying to clean up the left over damage from the Dope-Smokin-Old-Man I've been dubbed the Longhorn Freak/Fanatic/Expert, I just hope I can live up to it. Need to pick up the one ton Longhorn with a PONTIAC 350/350soon. Thanks every one! Check out The Longhorn Webite. If you need a pic posted, E-mail me at longhornmail@yahoo.com Andy, in Columbus Ohio

03-22-2002, 09:06 PM	#7
Gordo Registered User Join Date: Jan 2001 Location: Killingworth, CT. USA Posts: 3,378	10-4 ------------------ 1971 C10 swb stepside 350/700R4/3.73posi Killingworth, Connecticut __________________ 1971 C10 swb stepside 350/700R4/3.73posi (retired as of 4/22/03) 1998 S10 short bed 2002 S10 Blazer 1942 Oldsmobile 1958 Massey Harris Pony 1951 Wife Killingworth, Connecticut May those who love us, love us, any of those who do not love us, may God turn their hearts. And if God is unable to turn their hearts, may he turn their ankles so we may know them by their limping. A man who works with his hands is a laborer; a man who works with his hands and his brain is a craftsman; but a man who works with his hands and his brain and his heart is an artist.



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