Question about 1994 Isuzu Pickup
Hi I just bought a 94 isuzu pickup with the 2.3 liter motor and 188,xxx miles on it. When I first got it it had a little bit of a loping idle and the guy had the idle turned way up. I checked the vacuum lines and hooked them all up and replaced the bad ones, that didn't work. So I pulled the carb and replaced all the gaskets and seals, and got new plugs and wires. Now the loping idle is worse. It's driving me crazy because sometimes it will die when i stop or shift into nuetral, and when its cold and I put it in nuetral it will rev up realy high all the while loping. I tried to check the timing but it wont idle steady so I can't get a good reading. Can anybody please tell me some other things I should check? I don't know what to do at this point. Any help would be greatly appreciated.
Thank You, Aaron
I have a 91 pickup with the 2.3 engine. The problem that you are having is likely the same problem I have - and it is caused by the Mixture Control Valve. It is a white plastic barbell shaped device in a holder on the inside fender wall. There are two vacuum hoses going to it - one small diameter and a larger one. Air enters the bottom of the valve and is drawn through the larger hose. The amount of vacuum on the small hose regulates the amount allowed through the large hose. I haven't found one at a parts store nor have I found one in a junk yard just yet. The Isuzu dealer can order one, but as the parts guy said, "Isuzu is very proud of their part". It costs about $150. If you want to check yours, there are several things you can do: first, run the vehicle and put your hand under the valve - it will **** a lot of air all the time. You can pull the valve off the truck and pry the bottom off the housing. You will probably see the same thing I did - broken pieces that used to stop the air flow through the valve. Until you get a replacement, you can try what I did: 1. Pull the small vacuum hose off and let it lay loose, or 2. Pull the small vacuum hose off and let it lay loose AND block the large hose (or the bottom of the valve). In either case, you have to adjust the fast idle screw and/or mixture screw on the side of the carburator. If you adjust either screw, write down what you did, in case you get a new valve later. The diference between 1 and 2 is that 1 will run good once it is warmed up but will want to stall until it warms; 2 runs good both when cold and warm, but will idle faster than it should. Neither of these will make the truck run like it should, but it is a 100 times better than trying to drive it with the loping.
Posted on Dec 13, 2009
THE CARB MAY NEED TO BE REBUILT OR REPLACED ALSO CHECK OUT THE AIR FILTER OR THE INTAKE GASKETS MAY BE BAD
Posted on Nov 15, 2009
Testimonial: "thank you"
Capouellez, I did step one, and my truck has been running great. I am going to replace it eventually, for but a little while this helps. thanks a bunch, you were a lifesaver!!!
LW, 26 Fmale, Springfield Mo
Posted on May 01, 2010
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Posted on Jan 02, 2017
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Apr 16, 2014 | 1994 Isuzu Pickup
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