1991 Blazer S10 4WD-4.3L TBI -Automatic Trans. 190,000 miles

Blazer cranks fine and drives great. At idle, in park or in drive, the engine will act like it wants to cut-off, but doesn't. This will happen every 10-12 seconds after the engine reaches normal operating temperature.
Has new fuel pump, new fuel pump filter, new Idle Air Control, new temp coolant sensor, and new spark plugs. Any help is appreciated. Thanks.

 

How does the fuel spray from the injectors look?

 

The injectors spray looks good. Don't see any problem there.

 

Have you had anyone check the codes on it yet? Thats how mine started acting and then it got to where it would die at stop signs an such and then it started cutting out after it got up to running temp. The codes said map and o2 sensor....gonna go get em pretty quick here and I'll let you know if it fixed it.

 

Which temp sensor did you replace. There is one on the side of the passenger side head and one by the water inlet. The one by the water inlet is for the ECU. My guesses would be IAC, Temp Sensor and EGR Valve Leaking by or a vacuum leak. If the EGR is leaking by it will affect your idle.

 

Replaced the coolant temp sensor at the front of the engine.

 

My truck has gotten worse with it now skipping badly and backfires sometimes. When the engine is cold it runs fine. Also I have noticed a funny order when it gets warmed up now.

 

ive been having the same issues but when i drive the car the engine cuts off and loses power and it stalls when i come to a complete stop, would appreciate if u figured out what was wrong with your car.

 

Mine is the same year and model, 206,500 miles, and i've replaced all the vacuum hoses and the two temp sensors. Headed to a friends later to diagnose. Has anyone made any headway?