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#1069192 - 01/13/21 01:18 AM 85 SS acceleration  
Joined: Sep 2016
Posts: 37
fhorta Offline
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fhorta  Offline
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Joined: Sep 2016
Posts: 37
Bakersfield Ca.
Hello all. Having problems with following.
After warming up car, put in drive and takes off ok, but shortly thereafter starts to stall. I keep gas pressed and then after about a second or two car takes off again with no hesitation until i come up to a stop then same process.

Here are things i have noticed as i tried different solutions:
Fuel and air mixture screws-I notice no difference after turning them either direction. Only difference is if they are both out completely then car will not stay on. Even when plugging a vacuum gage.
Gage goes up to 20 and fluctuates lightly up and down to 19 and 21. It does this before turning screws even. When turning screw/s in or out it stays the same.

When i revv it up in park it goes to 20k rpm somewhat smoothly, but after that stalls as it goes into higher rpms. I see no smoke from tail pipes.

So in idle, rpms fluctuates between 9k and 10k rpms. Sometimes goes down to 8k and bounces around between 8 and 9.

I tried advancing and retarding time but just can't get it right. Carburetor is quadra jet Rochester. Its on a Chevy small block 305. Any ideas, suggestions, comments greatly appreciated.

#1069217 - 01/14/21 03:19 AM Re: 85 SS acceleration [Re: fhorta]  
Joined: May 2007
Posts: 4,934
Buick Runner Online content
10+ Year
Buick Runner  Online Content
10+ Year
Member

Joined: May 2007
Posts: 4,934
Dharma station 1 the Hydra
Do you have an analog dwell meter for checking the fuel M/C solenoid dwell?


SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.

2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.

Never argue with an idiot.
They will just drag you down to their level and beat you with experience.
#1069220 - 01/14/21 05:42 AM Re: 85 SS acceleration [Re: Buick Runner]  
Joined: Sep 2016
Posts: 37
fhorta Offline
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fhorta  Offline
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Joined: Sep 2016
Posts: 37
Bakersfield Ca.
Hello. No i dont have one analog dwell meter.

#1069228 - 01/14/21 04:00 PM Re: 85 SS acceleration [Re: fhorta]  
Joined: May 2007
Posts: 4,934
Buick Runner Online content
10+ Year
Buick Runner  Online Content
10+ Year
Member

Joined: May 2007
Posts: 4,934
Dharma station 1 the Hydra
Then you need to get one, otherwise you are just adjusting things blind.


SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.

2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.

Never argue with an idiot.
They will just drag you down to their level and beat you with experience.
#1069240 - 01/15/21 02:06 AM Re: 85 SS acceleration [Re: fhorta]  
Joined: Dec 1999
Posts: 11,792
86ttop Offline
20+ Year
86ttop  Offline
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Joined: Dec 1999
Posts: 11,792
Brooksville, Fl
When was the last time you changed the fuel filter where the gas line enters the carburator??


Leo Paugh
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#1069249 - 01/15/21 04:34 PM Re: 85 SS acceleration [Re: fhorta]  
Joined: May 2007
Posts: 4,934
Buick Runner Online content
10+ Year
Buick Runner  Online Content
10+ Year
Member

Joined: May 2007
Posts: 4,934
Dharma station 1 the Hydra
Also when you adjusted the timing, did you disable the computer advance? The idle mixture screws ard supposed to be set at 3 and 3/8 turns out. Idle mixture and curb idle speed is adjusted with the car in drive. You need at least an analog dwell meter to see how the computer is responding to adjuetments.

Sounds like the OP has an off idle stumble which can be caused by several things. Bad accel pump, incorrect float level, incorrect fuel pressure, vacuum leaks, incorrect throttle valve angle, incorrect timing, etc.


SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.

2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.

Never argue with an idiot.
They will just drag you down to their level and beat you with experience.
#1069272 - 01/17/21 05:47 PM Re: 85 SS acceleration [Re: Buick Runner]  
Joined: Sep 2016
Posts: 37
fhorta Offline
Member
fhorta  Offline
Member

Joined: Sep 2016
Posts: 37
Bakersfield Ca.
Thanks for all replies. I will work on getting meter. I have not changed fuel dilter recently but don't use car much. Maybe 2 to 3 thousand miles a year if that. As far as computer disabling for timing, computer is obsolete as previous owner somehow disabled to bypass a code that prevented car from psssing smog or something. I will look into suggested issues and post back.

#1069279 - 01/18/21 01:10 AM Re: 85 SS acceleration [Re: fhorta]  
Joined: Feb 2020
Posts: 173
88ssBrent Online content
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88ssBrent  Online Content
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Joined: Feb 2020
Posts: 173
Friendsville,Tn
Change the filter first. Its at the inlet of the carb very easy. I had the exact symptoms as you and that was it. It wasn't dirty at all from what I could tell but it fixes the issue.

#1069280 - 01/18/21 04:20 AM Re: 85 SS acceleration [Re: fhorta]  
Joined: May 2007
Posts: 4,934
Buick Runner Online content
10+ Year
Buick Runner  Online Content
10+ Year
Member

Joined: May 2007
Posts: 4,934
Dharma station 1 the Hydra
Originally Posted by fhorta
Thanks for all replies. I will work on getting meter. I have not changed fuel dilter recently but don't use car much. Maybe 2 to 3 thousand miles a year if that. As far as computer disabling for timing, computer is obsolete as previous owner somehow disabled to bypass a code that prevented car from psssing smog or something. I will look into suggested issues and post back.


This may be your issue here. Removing the computer is expensive, complex, zero performance improvement, MPG decrease, and loss of road legality. Often when a previous owner tampers with the computer of emission system they make the car run worse, then sell the basketcase to an unsuspecting buyer. Since we do not know what the PO did to your car, we won't be able to help you that much online. Somebody needs to look the car over in person to figure what was done and how to correct it.

To delete the computer, both the carb and dist need to be changed out for non computer controlled versions. Also an aftermarket lockup kit is required as the computer controls that. The factory computer system is all or nothing, if any part is missing the fomputer will default to limp mode. Since you live in CA which has the strictest emission laws and testing in the country, you will need to revert the car back to full computer control. Perhaps the PO still has some of the original parts?

Last edited by Buick Runner; 01/18/21 04:22 AM.

SBC powered 1987 Regal with TES headers, ZZ4 intake, ZZ4 PROM chip, mini starter, THM2004R, 2500 stall converter, 2040 cam, CCC system, and 3.73 posi rear.

2008 ex NPS P71 Crown Victoria, cop motor, cop shocks, cop brakes, and Jmod.

Never argue with an idiot.
They will just drag you down to their level and beat you with experience.
#1069333 - 01/22/21 02:20 PM Re: 85 SS acceleration [Re: fhorta]  
Joined: Mar 2000
Posts: 5,595
upflying Offline
20+ Year
upflying  Offline
20+ Year
Member

Joined: Mar 2000
Posts: 5,595
Reno, NV
I agree with Buick Runner, OP has a car that wont pass a California smog check. Until the car is returned to stock with an operating computer controlling the carb and distributor, it will remain parked in a garage.
Sorry for the bad news fhorta, California is at war with old cars that don't run right and won't pass smog. California tried to take my car away with a $1000 offer to junk it..one of the reasons why I left and moved to Nevada.

Last edited by upflying; 01/22/21 02:21 PM.

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