'88 Cutlass Ciera rough idle/stalling
 

'88 Cutlass Ciera Brougham w/ 3.8L It began with a starting issue. It cranks fine, but will die if you don't keep the revs up high enough. Then it began stalling out while in gear. First reverse, then while in drive. I took it to a shop and they replaced plug wires and the ignition control unit and the mechanic suggested I come in to get the injectors cleaned out. The car does run smoother, but it does still feel like it wants to stall out on me at times. Would an off the shelf cleaner do the trick or should I invest in something more thorough? What that be the only thing to look at as the cause? If the injectors are dirty, wouldn't I have noticed that when I first test drove the car? I've only had it about six months with the problem occurring the last 3 months of that.

I would certainly try an off the shelf injector cleaner first, it's cheap. Also, check the usual suspects: vacuum leaks, dirty idle air passages, dirty throttle body, airflow sensors, air filter, and maybe fuel filter.

88 Cutlass Ciera rough idle/stalling
 

Ok guys having problems with my 6.2 MPI EFI. Idle is rough and anything above say 1500 rpms runs perfect. Heres what I have checked and replaced so far. Checked compression 170lbs on all cylinders, replaced IAC valve, replaced plug wires, replaced plugs, replaced cap ad rotor. Only runs rough on idle wondering if it may have a couple bad injectors. This is something I just noticed tonight, when I run my electric downrigger at idle engine runs rougher. replaced batteries and alternator is charging fine, Thinking maybe an electric problem. possibly to low voltage to run good at idle? Batteries are fully charged though. anyone got any ideas?
Thanks

@Iflylow: Thanks for the response. The injector cleaner made a big difference, and I went ahead and switched out the fuel and air filters. Still plan on doing a little further investigating just to be sure. Thanks again.

88 Cutlass Ciera rough idle/stalling
 

It may just be a trait of the inline six i have a 66 mustang also and it runs quite rough at idle too and then smooths right out when you start driving

I have worked on those motors a ferw times and I've had to change out the throttle positioning sensor a few times on a few chevys and some oldsmobiles. Sometime they trigger the check engine light sometimes they don't.