Sputtering at low RPMS
 

Hey guys new to the forums and have a question. My tranny was in limp mode and with some reading had a hunch it was the shift solenoid A and ding ding ding I was correct. So now that's all good have all my gears back and shifting fine. But now at low RPMS between idle and 2500 it will cut in and out jerking around, don't really know how to describe it more than that. Once past 2500rpms it doesn't do it again. Also if I give her a lot of gas from idle it doesn't sputter either. I have a 2000 blazer 2 door automatic tranny

Steven, welcome to the Blazer Forum. A serious question. Are you describing an engine misfire or are you describing a transmission malfunction? We need to be certain.

If it is an intermittent engine misfire, there are two big problem areas in the second gen Blazers.

1. Secondary Electrical (distributor/spark plugs/wires/cap/rotor)
2. Fuel system (fuel pump/filter/injectors).

I could also imagine a big vacuum leak or EGR malfunction could cause your symptoms, but that would be a longer shot.

Usually we advise all people with misfires to verify a number of things and bring the secondary electrical system up to a certain standard with some new parts before starting to chase misfires (which can be pretty difficult). A lot of the time installing the secondary electrical parts cures the misfire.


Strategy:

• Display and repair any OBD2 codes that are present.
• Replace Distributor Cap/Rotor with new AC Delco parts (just do it)
• Check all plug wire terminals visually and check plug wires with an ohm meter.
• Replace Spark Plugs with correct new AC Delco Platinums (just do it). Don't break the plug porcelain on #3.
• Check cam sensor retard to make sure it is 0° ± 2±° (requires capable scanner). This is adjutment of exactly where the rotor points when the spark plug is fired and is NOT related to ignition timing. Adjustment is done by modifying the distributor hold down so the distributor can be turned a little.

note: cheapest scanner setup I know of for displaying cam sensor retard is Car Gauge Pro for Android and the BAFX Bluetooth OBD2 adapter on Amazon. About $30 total for both.

If that does not cure the problem, fuel system testing is in order.

Do all 4 fuel system tests in the sticky at the top of the second gen forum and report. You can borrow nice fuel pressure guages from local parts stores with deposit and make up the dead end plugs according to the sticky. We will help analyze your results.

If you have any question, just ask.

Really think it's a misfire. Tranny shifts fine. Just bought some spark plugs today and I'm hoping to switch them out. Hopefully that fixes problem.

AC Delco 41-993 plugs with a gap of .060" are what you need. Don't bother wasting time and money experimenting with other plugs. Plenty of other people have saved you the grief.