1993 Trooper 3.2L DOHC. Will start after sitting for an Hr or so. Will run for max. 7 min at idle. When engine starts to die sounds and feels like an old chevy with the choke stuck. Carb cleaner will keep it running. Can rev it to any RPM when running. Changed the fuel filter and throttle position sensor a few days ago but didn't fix the problem. Is there a cold start circuit on these engines or is it all computer controlled through the injectors? Also where is the fuel pressure regulator located?

SOURCE: 98 Isuzu Trooper stalls on cold start, idle issues..

I had the same issue on my 99 Trooper.

It would usually start when completely cold, but idle around 2k RPM.
It would drive fine. But if I shut it down, ran into a store, and came back out, it would start but immediately idle.
Had to ride the gas a little to get it into gear.
The Check Engine light has been going on and off for 6 months or so.

I took this to my local trusted repair shop (no Isuzu dealers within 200 miles).
The diagnosed the light, and found that the Intake Gaskets were bad or leaking.
The idling problem was related to the car not being able to control the amount of air coming in.

They replaced the Intake gaskets by the next day, and I haven't had a problem since. And no more check engine light, which has been on half a year.

Here's some details from my bill:
(1) Intake Gasket set $107.95
Misc materials $21.00
2.1 hours of Labor

The total cost to me was $345.00, and I definately don't feel gipped.

SOURCE: my 1992 3.2 petrol trooper starts an idles fine

check for spark at the coils under load. May have to change some ignition coils.

SOURCE: runs poorly when warm, but great when cold

have you checked your o2 sensors?

SOURCE: No fuel pressure. Replaced filter, no help

fuel pump bad

SOURCE: rpm hunting

check for a vaccuum leak this is where i would start if it rolled into my shop. possibly a PCV valve sticking or a hole in the hose, this hose should run from the valve cover, or crank case and then to the intake, or carb.