I picked up this 88 Dakota and I’m wanting to take it back to the stone age with what’s already in it. Smog pump, charcoal can, most vacuum lines, factory air cleaner housing, all gone. I want to eliminate the iac and fab a manual throttle spring stop like a carb.

emissions don’t matter. I come from a history of carb’d trucks and cars and I want this truck to look as simple as possible under the hood and run strong. I read here the coolant temp sensor controls fuel delivery so maybe I can trick that sensor or the iac into doing what I want. I have been a certified mechanic for several years but now in a diff career field So I don’t do it everyday anymore.

with that said I’m getting this surging at idle and it stalls at stop lights. When I throttle it from the tbi it spools up well.

eventually I’ll open up the exhaust and convert it to electric cooling fans like the Shelby Dakotas of the same era but need to be able to make a 2 mile beer run without stalling first. Anybody with any pertinent suggestings, procedures to get what I’m going for I could def use your insight.

(This all started with the removal of an old unused and unsightly alarm system and a spare tire that was dry rotten and flat and spiraled out of control from there lol)

lastly the 3 2 pin pigtails that plug into vacuum sensors (3 sensors each with 3 vacuum nipples)
Can I block those nips off, reroute to achieve desired results, trick those sensors with a resistor or jumper wire or something similar since smog and egr and evap have all been removed?

 

You have a vacuum leak somewhere. Fix that, and your surging problem will likely go away.

 

What HeyYou said.

And a few items.

1) EVAP hurts nothing when it works right. That's ONE of those three SOLENOIDS back on the back. They aren't sensors, they're solenoids.

Did you look at the VECI under the hood?

2) EGR hurts nothing when running right, and helps gas mileage.

3) Disable everything? You realize there is no, none, zero advance in the distributor, right? You CAN set base on it on the LA based 3.9L (239ci, not 289ci!) but all advance is done by the ECU.

So.

Step 0 - Find and fix the vacuum leak. Old troubleshooting tricks work fine with the hoses off. You DID plug all the nipples on the intake, and made sure you don't have one on the replacement carb, right?

Step 1 - find a uneven fire V6 distributor that's close to the 3.9's pattern (closest is a few Buick V6 years) and can fit into the back.

Step 2 - Remove the ECU. All it does after you remove the TBI and put a real distributor in there, would be to turn torque converter lockup on and off, basically. Oh, it also controls the ASD; but that can just be wired to the ignition switch so that turning the key off kills what's downstream of it.

Do remember, the fuel pump is set up for a return type system at 14.5psi ; you'll need to put a return type regulator going to the new carb to regulate it down.

Do you have a copy of the factory service manual for a 1988 Dakota?

EDIT: One lucky thing - ALL of the control for the cruise is in the servo there on the driver's fender on a 1988; that means you won't have to fiddle with that any once you remove the ECU.

RwP