Fixing a Sticky Accelerator

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Take off the hose clamp on the rubber flex pipe which is attached to the air intake. This is located by the accelerator wire linkage on the passenger-side of the engine. You only need to remove the side of the rubber hose that is closer to the engine (not the side closer to the rad). Also, you only need to get it off to the point where you can squirt some carb cleaner into the manifold. Take the carb cleaner - which you can buy in a spray can for about $6.00, attach the skinny plastic tube to the can and squirt the liquid inside (be sure not to lose the plastic tube into the manifold). There is a butterfly valve inside the housing which is binding, causing the problem. You need to use the carb cleaner to clean away any gunge that has collected. Run the engine while doing this. I have heard that the engine will not run if this hose is completely disconnected but since in my case I only diconnected it partially, it ran OK. I used about 1/2 of the carb cleaner can (saving the rest in case I need to do this again). The problem seems to be solved for now.

Now the difficult part - putting the hose back onto the manifold: The area is very difficult to get your fingers into and it may take a while to get it on properly. *Be sure that the hose is seated all the way around, especially on the bottom where it is difficult to see*. You can use a flashlight and fingertips and various contortions to do this. The reason that this operation was difficult (for me) is that the hose kept "wrinkling" on the underside so that even though the upper side was properly seated, the bottom was not. Also, I *think* that the hose on my car was not properly seated before I performed this operation. I wouldn't be surprised if the mechanic failed to do this properly as it took me about 45 minutes and about a litre of sweat to get it back on!

Another Solution

Check the throttle butterfly valve stop position adjustment. On my 1993 240SX LE the nut on the adjustment screw had come loose, allowing the valve to go too far when the accelerator was released, and the valve would bind. Adjust the stop position with an Allen key, then tighten the nut with a small wrench.

Yet Another Solution

Take off the black sleeve coming from the air filter box going to the manifold. Take off the sleeve closest to the manifold. You might need to take off the hoses that are connected to the sleeve, in order to move the sleeve out of the way. When you remove the sleeve, you will see the butterfly valve inside. You can move open it by pushing the choke back (located next to the butterfly valve). You will see all the gunk collected over the years. You can buy some of the Carburator cleaner or some WD40. Make sure the car is turned off before spraying the liquid into the manifold, otherwise you will choke the engine. Get a clean rag and spray the liquid into the butterfly valve and clean the butterfly valve and the surrounding area.

Keep on cleaning until you notice that the butterfly doesn't stick anymore. Becareful not to turn the car on otherwise you will choke the engine and you won't be able to turn it on for a hour or so!

Contributors include: Bob Gatzke, Hugo Figueroa