First off, this is my first post here! I've been reading several forums that have provided some great info about these trucks. I come today looking for some advice.
My 1989 Dodge ram 50 2.0L, 5Spd, factory mikuni carb is revving up to about 4K upon a cold start. Eventually she will idle back down, but it can take several minutes. I've had a friend who knows much mkore about these motors come take a look and he's done the following things:
1. Removed carb and cleaned.
2. Adjusted carb
2. Adjusted timing (by eye)
3. Cleaned distributer cap
4. Checked plugs & wires
5. Checked hoses
... and the problem persists! His final conclusion is that the electronic choke is bad causing the motor to rev so high when starting. And from what I can see and have read, this is riveted to the carb. Eventually the butterfly (in the carb) does back down, but like I said it idles ridiculously high for several minutes. The only other thing that was recommended for me to try was replacing the o2 sensor (which looks old).
I recently bought this truck and the previous owner said it had been sitting for about a year and that he noticed this problem from time to time (but trust me, it's every time the truck sits for more than 45 mins or so). The truck runs and drives great once the idle calms down. My only complaint would be that it holds onto the gas a bit longer than it should in between gears frequently (maybe a result of this funky carb?).
I've can't say that I've read too many positive posts about these mukini carbs and the Weber is a great replacement when the times comes - which sounds like now for me.
I'm trying to provide as much info as I know without going overboard. I'd like some thoughts that you may have around this problem. Much appreciated!