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Sluggish Acceleration from a stop


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I just bought this sweet car a few days ago and it has an issue im having a hard time putting my finger on. It only has 65,000 miles on it and I got it for a thousand bucks =D It is an 81 gl 1.8 2WD auto

 

Idle is ok. When I give gas in park or neutral, everything is good. When I put it in gear and accelerate, I must do with a very soft touch until about 1600-1800 rpm where it picks up strong otherwise it wants to stall under a load. From a stop pointed uphill, dont even think about it. Fuel pump and fuel filter have been replaced with new, and I have sprayed carb cleaner in the carb several times. It has fresh gas , and I have put about 500 miles on it already.

 

Please help !

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#1 - check for vacuum leaks as already mentioned.

With vehicle running spray carb cleaner or similar around the vacuum lines to see if there is any change in idle.

 

with any type of carb - if the vehicle has been sitting for any length of time, it is possible it may have plugged up fuel passages, causing symptoms like you are describing - in more extreme cases, the engine will fire with a shot of starting fluid, but not be able to continue running on its own, because fuel flow is being restricted in any number of passages.

 

Basic carb function info: http://en.wikipedia.org/wiki/Carburetor

 

good luck.

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So to improve 1st gear acceleration would I have to replace Hitachi carb ?
Not necessarily. Being in Socal, replacing the fuel delivery system legally is a chore.

 

For $10-$15 you can probably replace every vacuum hose in the engine bay, just do it one at a time.

 

Run some Seafoam through the fuel system.

 

Check your ignition timing.

 

Not sure of your mechanical skill, but if you want to keep your car running in California you are going to need to learn it backwards and forwards.

 

Oh and we like pictures. An '81 with 65,000 mi. must be witnessed

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+1 on checking the timing.

 

Also could be the accelerator pump on the carb and/or a clogged idle jet.

 

No amount of carb cleaner is going to help you if the jets are clogged.

 

I would suggest removing and cleaning the jets.

 

You need to remove the top of the carb for this. Be sure to take care not to damage the gasket when you do this.

 

A carb re-build kit would be handy but in my opinion not essential at this stage.

 

My recomendation would be to service and tune the engine as best as possible (getting to know the animal) before upgrading or modifying.

 

cheers

 

Dirk.

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My advice: start with the least expensive fix first (if indeed this fixes it) - replace all the vacuum hoses. They get brittle and then crack if the car sits for a long spell. Or they get soft and then ballon out when the car is up & running again, making weak spots (like arteries)

 

Another piece of advice: run Marvel Mystery Oil through the gas tank at all times. I add some every time I fill the tank.

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  • 10 months later...

It appears that a carb rebuild and plugs & wires fixed the problem. The carb was clean inside, but it was leaking air, and the carb tuning was all out of whack. Thanks for all the advise!

Edited by bluebonnet81
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