carburator problem

[gearshift101]

Hello All,

Here's what's happening! I'll start the car, it will idle. I'll put it in drive and start to accelerate, then when I reach a certain point with the accelerator pedal it would feel like it's going to stall, I will then take my foot off the pedal and it will go back to idle position and stay running, so I checked the fuel pump pressure and volume for which is ok!

So now i'm at a lose??? Also I've been trying to locate a rochester quadrajet 4 bbl carb rebuild kit for a 1985 Olds 88 w/ 307 eng. any help here would be greatfully appriciated.

Thanks,

Al

[kmohr3]

possibly a problem with the power circuit in the carburetor. maybe a bad accelerator pump diaphram/plunger in the carb. I would think you may need a full carb overhaul - it's worth a try if you can find a kit

[gearshift101]

Originally Posted by kmohr3

possibly a problem with the power circuit in the carburetor. maybe a bad accelerator pump diaphram/plunger in the carb. I would think you may need a full carb overhaul - it's worth a try if you can find a kit

The carb has two electrical fittings on it, on the top is a blue connector, and the other is on the front right side is a plug with 3 wires coming out of it. nothing is connected. and what would they connect to.

Power circuit? Please explain!

Thanks. I kinda thought it would need a rebuild . But I can't seem to find a rebuild kit for this carb.

Al

[kmohr3]

I'm not really a GM carb person - most of my experience is with Solex and Zenith carbs. However, the power circuit of a carb means when you press down on the gas pedal a certain amount of raw fuel will be dumped into the carburetor's venturi. Every time the gas pedal is pressed - more raw fuel is dumped. This is in addition to what is being metered through the carb via the main jets and idle jets, etc. On VW's there was a "dump" tube that sometimes became plugged. I think on most American cars there is a plunger type of setup that is part of the power circuit - this should be included in the carb kit -

[kmohr3]

I dug around in my garage a little and found an old Command Control Carburetor book for 81 thru 88 GM cars. According to my book you should have a Rochester E4MC on it. From the picture I have it looks like it could have an idle speed control and a throttle position sensor on the left front area of the carb. Also it looks like it has a connector for a mixture control solenoid on the top. Also it may have a place for a wire to go on the electric choke on the rt side of the carb. I think you said these were unplugged? See if you can find the wiring and plug these things back in. I would think if this is the right carb on the vehicle you should find the harness with the unplugged matching connectors within reach. Maybe someone has modified this thing - I think some of these carburetor controls send and receive signals from an ECM.

[kmohr3]

By the way, Advance Auto lists carb rebuild kits for them. There's one in East Orange - probably not far from you. They can usually order one up overnight. About $20

[gearshift101]

Originally Posted by kmohr3

By the way, Advance Auto lists carb rebuild kits for them. There's one in East Orange - probably not far from you. They can usually order one up overnight. About $20

Thanks, kmohr3

I will give advance auto a call! even though I purchased a remanufactured rochester quadrajet 4bbl carb from ebay, for 99.00 not a bad deal. this price is for a non-computer controlled carb, for which i need. what I did was take a 307 engine from an 85 olds delta 88, and fabricated the motor mounts to fit into a 85 GMC Vandura 1500 van, that I will be using for flea-marketing.

But I will get a rebuild kit for the computerized carb I have, and resell-it on ebay!

Again Thanks,
gearshift101

[gearshift101]

Ok! got the remanufactured non-computerized carb, installed it. Now while driving when I reach about 40 -50 mph is boggs out/ stumbles like it's not getting any fuel, then I'll take my foot off the pedal for a second and it would return to normal idle speed.

Like I mentioned in a newer post, I had a simmular problem with my ford f150 it turned out to be the transmission module, the vacume line was filling up with trans fluid. I replaced the module and it ran good as new.

what I need to know now is ? where would the transmission module be located I don't see one, Unless it's the three wire plug, plugged into the driver side of the transmission?

or what else could cause this bogging problem?

Thanks, Al