Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
2022 Chevy spark 1.4l n/a with 25k miles, stalls when coming to a stop and struggles to restart right after, drives decent once it starts At times it feels like it misfires at idle and has set a p0300 pending code one time. Have cleaned and relearned the throttle body just because that's what it feels like, have checked fuel pressure during stall condition and found it stays at 60 psi, compression okay (140-160 psi). Spark plugs okay, Fuel trims are rich around -10 to -15 sometimes (but looked at known good vehicle and also saw rich readings, not sure why) purge solenoid not stuck open and still stalls if I disconnect it, history shows it has had major engine work recently (piston and rod bearings) Also, the valve body has also been replaced and if you put it in neutral as you're coming to a stop it won't stall. Found a similar vehicle and swapped o2 sensor, maf sensor and throttle body for testing purposes and concern is still present. Smoke tested the intake and found no leaks. Also found that maf reading seems to read more airflow at idle at least, about 1-1.5g/s compared tonthe known good vehicle.
What should i be looking for? Dont know where to start and dont like just doing random testing. Any suggestions are appreciated.
, the valve body has also been replaced and if you put it in neutral as you're coming to a stop it won't stall
This to me sounds like the TCC (Torque Converter Clutch) is stuck applied.
I've never worked on one of these that new. She's had an awful lot of work done for being a relatively young car.
I don't know that I have a really good test for you to prove it. I don't suspect the solenoid would be electricaly open without a trouble code. Likewise I would also suspect the control pid would reflect proper command. You could try a bidirectional test with the scan tool, or try activating the TCC solenoid manually with a power probe and listen for a click, but much like any solenoid, click doesn't mean the oil is being directed to the correct passage.
A pintle jump on a current ramp may help prove or disprove movement of the solenoid in the body. But really, I think that putting it in neutral as you come to a stop says it all.
Topic Author
