I recently bought a 1987 FJ60, and love it. BUT I can't find anyone in my area that really knows how to make it run properly. I had a new DUI distributor installed and it seems to work great. My local mechanic rebuilt the carb, including a new fuel cutoff solenoid, and had to wire the solenoid direct (per forum) and bypass the "computer". That made it run "OK" but I still have 3 issues. (1) It does not idle well (not terrible), (2) when driving at lower RPMs (up to 1500) it has a slight "surge" that you can feel, and (3) when I turn on the air conditioner at idle, the RPMs go up and down from about 1200 to 1800 -up, down, repeat, repeat. I think that the idle and "surge" when driving are related, but that is just a guess. The vehicle was desmogged by the Cruiser Shop in Dallas, and did not run worth a darn when I got it back, but it obviously had carburetor issues. I would appreciate any help anyone can offer. Sorry about being a rank beginner!
Carburetor issues after rebuild - 87 FJ60 (1 Viewer)
- Thread starter SOD
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The oscillating throttle might be caused by a faulty vacuum switch (or the wire may not be connected to it). See pictures below for reference what it looks like. Just a single wire connects to it.
Pull the wire from the vacuum switch and ground the wire to the body. Then see if the surging went away.
Pull the wire from the vacuum switch and ground the wire to the body. Then see if the surging went away.
- Thread starter
- #3
OSS, thanks for the info. I can't find anything that remotely resembles the vacuum switch. Is this something that might have been removed in the desmog? Should it have been? What does it control?
Also, I read one of you comments from some time ago about the charcoal canister, and I periodically have a fuel smell in the vehicle, so I think that I will test that. I appreciate your help!
If the emissions computer is still hooked up, (behind the driver's kick panel) that vacuum switch wire needs to be grounded. You may not have the vacuum switch anymore, but it's wire is still poking out of the wiring harness in the engine bay. Left side, midway.
The vacuum switch detects vacuum. It tells the emissions computer to activate the fuel cut solenoid in the carb when decelerating. Although it's an added smog component, the system (deceleration fuel cut) prevents afterburning in the exhaust pipe and slightly better engine compression braking. The primary purpose though was to prevent excess
fuel from entering the exhaust during deceleration to prevent overheating the catalytic converter.
The vacuum switch detects vacuum. It tells the emissions computer to activate the fuel cut solenoid in the carb when decelerating. Although it's an added smog component, the system (deceleration fuel cut) prevents afterburning in the exhaust pipe and slightly better engine compression braking. The primary purpose though was to prevent excess
fuel from entering the exhaust during deceleration to prevent overheating the catalytic converter.
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- Thread starter
- #5
Great, thanks for the info - I will check it out!
the surging with the AC on is because the AC idle up screw is set too high. On the front facing side of the carburetor there is a vacuum diaphragm that is connected to the primary throttle shaft. Part of that linkage has a idle up screw. I think you return the screw out to reduce the speed. Your idle up should bring the rpm from 650 at normal idle to about 1100 with the AC on.
If the Idle Solenoid is grounded to the carb, the Vacuum Switch for decel-cut will not have any effect on it as it is now removed from the control circuit. It's now going to be only On/Off through ignition switch power.
Just a guess, but if your ICS was replaced by mechanic with a cheap Chinese one (most likely, as OEM are NLA), they are really hit and miss with function; they just don't seem to function right giving odd idle issues. Sometimes the small O-ring on the snout of the cheap aftermarket are dry and cracked and break up when installed.
Do you have the original ICS or can you get it back ? They almost never fail.
Ebay has some old stock Tomco or Carter (American made) once and awhile, but you'll have to find one that looks right for an Aisan 2-bbl.
Procedures for Carb and Idle adjustment are in the FSM avail here as a free pdf download.
Search for FSM for hell of a price.
Just a guess, but if your ICS was replaced by mechanic with a cheap Chinese one (most likely, as OEM are NLA), they are really hit and miss with function; they just don't seem to function right giving odd idle issues. Sometimes the small O-ring on the snout of the cheap aftermarket are dry and cracked and break up when installed.
Do you have the original ICS or can you get it back ? They almost never fail.
Ebay has some old stock Tomco or Carter (American made) once and awhile, but you'll have to find one that looks right for an Aisan 2-bbl.
Procedures for Carb and Idle adjustment are in the FSM avail here as a free pdf download.
Search for FSM for hell of a price.
- Thread starter
- #8
I adjusted the a/c idle up screw and it solved the problem with the surge with the a/c on. Made some adjustments to the mixture just by listening to the engine RPM and adjusted the idle speed adjusting screw, and it runs WAY better. I will put a tach or vacuum guage on it this week end to better adjust the mixture. Thanks!
- Thread starter
- #9
The ICS was the only one that I could find - bought it from Cool Cruisers in Dallas. I still have the old one, but it does NOTHING when you direct wire it to a battery. I will try to find another one or see if I can free up my old one. Thanks for the info!
- Thread starter
- #10
Sorry about being a Newby - where do I find the pdfs to download ? I looked all over the sight and don't see it. IT challenged, I guess.
If you don't get a 'Click-click' when tapping the ICS directly to 12v then it's most likely bad. Rare, but it happens.
Pdf downloads:
If you highlight everything, makes it easier to see the links
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Pdf downloads:
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