Help! 92 Dodge Pickup chokes/stalls around 55 mph

Maintenance/Repairs
1

I’m looking for insight from anyone more adept than I am when it comes to cars and trucks. My boyfriend and I moved out to the country a year ago and purchased a new-to-us 1st gen dodge pickup, a 92 D150 v6. It’s used once or twice a week at max and only has around 90k miles on it.

So a few months after we bought the truck, it stalled, or more like choked, out while driving on these country, hilly roads, at around 50 mph… it happened once and we didn’t think much of it. It happened again not too long after that, though, and we discovered we could push through the stall/choke by giving it a lot of gas… it sounds terrible, and shakes and sputters, but eventually catches back and starts to run normal.

As months passed, the problem happened more often. So we changed the spark plugs and wires recently. No difference. In a given 40 minute trip along 45-55 mph country roads, the truck will choke and sputter at least 5 or 6 times. It’s now so bad that sometimes giving it gas isn’t enough to fix the issue and we have to pull over.

We’ve got an appt scheduled with a mechanic, but I’d like to have some idea of what you all think before going in there. Our friends think maybe it has to do with the choke plate or carburetor. Thoughts? It seems to happen more often if the AC is on, and other than this, the truck runs great. It starts up fast and idles fine.

2

perhaps the timing is slightly off

3

Deleted…but I like jmcarc’s idea below of a vacuum leak.

4

There could be a vacuum leak someplace causing the engine to run extra lean at high speeds.

5

Clogged fuel filter?

6

Could also be a weak/failing fuel pump.

7

“Our friends think maybe it has to do with the choke plate or carburetor.”

I believe you have fuel injection, so you have neither of these.
Yep, 1) Fuel filter, 2) Fuel pump.

8

So the suggestion from the shop is a bad O2 sensor - we’re going to give it a shot, but if anyone has any further input that would be great.

9

O2 sensors rarely cause driveability problems.
Did the shop do any diagnostics to confirm the O2 sensor is bad, or are they guessing?
The cost of a sensor justifies some checking before they start trowing parts at the problem.
Does this engine have a MAF sensor? Would be worth cleaning it (and the throttle body while they’re at it).
Measure the fuel pressure.

10

+1 @circuitsmith

11

I wonder why you call it a 1st generation truck? Dodge has been selling pickups since 1921.

12

Thanks for your completely off-topic comment: 1981-1993 are considered 1st gen rams. So forgive me for saying pick-up instead of ram. No offense intended, but I’d appreciate only constructive feedback.

13

We have fun here @1stgendodge. Advice is given to keep the forum’s monitor happy.

Low fuel pressure or a restricted exhaust come to mind for your complaint. Because the fuel filter is so cheap and easily replaced doing so would be a good place to start.