3.9L Choppy Start-Up? [VIDEO]
I did not realize it had a computer I could read I thought it would be too old, I'm thinking lowering the idle might have just patched the problem and I may need to turn it up if I corrected the problem with a temp sensor?
I think it's too old to have the onboard diagnostic. I was looking at a 93 Dakota LE and it didn't have it. My 95 has it.
That's what I was thinking, I'm going to have to read up on how else to go about testing the temp sensor. Someone told me Dodges always had that double crank type of start but I think he is full of it. I just tested it again today and it still does the rough couple of seconds when it fires up even with the lower idle. Electric choke valve maybe??
I had a mechanic tell me the truck most likely does not have an electric choke valve and that the problem might be carbon built up on the valves/intake acting like a sponge absorbing gas. Told me to use Seafoam SPRAY with the large wand, if not then possibly a leaking injector.
Since I have no tach I really can't tell where my idle RPMs are at so everything is a guessing game. I think some people are onto something and my idle is turned up so I decided to try and crank it back down...which I'm not sure 100% how to do. I screwed the IAC screw pusher knub way back down/in and I will admit it does shift into and out of gear a bit smoother but still not where I think it should be, and that might not have been the correct way to adjust the idle? Now I am back to it starting up real choppy so I am now thinking possibly the idle was cranked up to compensate something else wrong with the choppy starting issue? It does not idle forward quite as aggressively now, but you can hear the engine idle up a little when I shift from drive into neutral before I backup. Is there a chance the starting issue is just a bad IAC; it works just not that "well" or does not extend fast enough or has lost some reach?






