Been addressed before but.....


USMC Iraq Combat
Trying to diagnose a hiccup in acceleration that I've read about numerous times before but doesn't seem to apply to my issue.

I have a 34,000 mile stock 87. It has the 28lb injectors,
Factory non-hot-wired fuel pump and factory regulator
Stock turbo
The car has Evans waterless coolant and a 160 stat
It runs perfect, until it heats up, and then the only problem is under light load, coming off a stop, it hesitates under acceleration. Giving it more throttle doesn't help, taking my foot off the throttle to let the RPM come down doesn't help. It's just a small hiccup until it hits about 25 to 30 MPH and it's fine. It doesn't cut out again until I am at a light, take off slowly, under light load, and it it starts again.
The problem is intermittent, it does do jt every single time, but it only does it once the car is hot.
I drove the car on the highway a few weeks ago and it's perfect while cruising, always has been.
I have a brand new NOS coil pack and ignition on it. I just upgraded to the 3" MAF and a translator. It has a turbo tweak chip for 93 octane and that's what I burn. I baby the car, it doesn't get driven hard and it doesn't leak oil.
It has a new AC Delco fuel filter and plugs with less than 1000 miles on them. This happens whether the AC is on or off.
Scan master numbers are all excellent, always are. It has a new AC Delco non heated O2 sensor. BLMs and INT numbers always near 128 no matter the temp outside. I live in S. FL and drive it in the summer also.
Should I look at cleaning the throttle body intake and IAC valve? This hasn't been done before by me.
Thanks for your input.
Plug wires? Age? Ohm good?
Injectors original? Have they been cleaned and flowed?
Pump needs a hot wire and probably needs a new pump if it is old/original.
Do you have a gauge or way to look at fuel pressure while accelerating?
I'd look at a new fpr as pm also.
Like TexasT said , need to know fuel pressure and should have a hot wire also .
Roger, thanks. And what would you recommend for a hot wire kit? Plugs wires would cause break up at all loads not just down low, correct?
Watch the scanmaster O2 number, first screen, when the stumble occurs does the display stay all low or high numbers?
Not sure about that but I will. What does it mean based on the high or low?

And asking about cleaning the IAC and throttle body intake? No one has answered.
And what would you recommend for a hot wire kit?
Edit: Looks like Same beat me to it........

Casper's or Racetronix both make a nice hot wire kit.
Link to Hot wire kit: Fuel Pump Wiring Kit for Turbo Buick (Hotwire)

Like already mentioned, fuel pressure being spot on is critical and with the issue you describe it would be very helpful to know what the pressure is while driving around and in the transition period when your leaving a stop light for example where the problem is occurring. Need to be able to watch it in real time and understand what it should be doing under vac and boost. Your fuel pressure regular might be failing and your getting a lean condition, a fuel pressure gauge would help identify if that's the case. If the fuel pump is old it's defiantly worth replacing for a peace of mind and knowing it's not a future problem, fuel pumps will all fail at some point in time,

This temporary gauge works well and is easy to use: Temporary Mount Test & Tune Fuel Pressure Gauge Kit (GM)

Cleaning the IAC and throttle body is easy so it's worth a try first and will cost very little.

Double check all your vacuum lines and make sure they are in good shape, if not they need replaced, same goes for the check valves inline.

You mentioned that you just upgraded to a 3" MAF and Translator. Double check that it's setup correctly for your combination. Make sure the MAF intake piping is properly sealed up and there are no post MAF leaks.

It sounds like you have a nice low mileage car that is worth the investment and time you will put into it. Even an original untouched low mileage car that has been well taken care of and stored inside it's entire life has a fuel system and electronics that are 35+ years old. Those items were never designed to survive that long without maintenance/replacement. There will come a time that those items need freshened up.
If the numbers remain low or high for the O2's during the issue, it will tell you if you are experiencing a rich or lean condition.
Problem was nothing related to fuel, plug wires, plugs, pressure.
It was the TCC solenoid which is common, as I found out.