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!
undefined I do strive to be a better "tech" everyday, though! My abilities are improving with diagnosing, but I have a lot more schooling to go! MY MAIN PROJECT NOW IS A 2001 Chevy Blazer ls 4.3l v6. Do I mention I have a P0300, recurring at every, 2nd ignition cycle. I have tried most everything and I could sure use some assistance, now! I have to get this car through California Smog, ASAP. Regards to you all;.....
P0300 code, A few random misfires ONLY at idle! Raise RPMs, snap throttle, all good. Misfires go to zero on all cylinders! Car is performing great on a drive.... Tried so many tests, I'm dizzy. Any and all assistance would be most appreciated. Give me a shout, regards to all.....
undefined I do strive to be a better "tech" everyday, though! My abilities are improving with diagnosing, but I have a lot more schooling to go!
Welcome to the club! :silly:
Which cylinders had counts, specifically? Which scan tool are you using? I agree with Juergen that an intake leak or valve issue is likely based on your description.
I agree with Juergen and Tyler, but would like to know if you actually feel the engine misfiring or if it's just setting a code for misfires.
I have seen GM vehicles set false p0300 when a cam/crank relearn needs to be done with the scan tool.
No apparent misfires felt... Rock steady n smooth. Ran a GM drive cycle, no code after 3 ignition cycles. All modules have not reset. Thanks for your reply, all assistance most appreciated!
P0300 code back after the 4th or 5th ignition cycle. thanks for the help, could sure use any/ all assistance with this one!
I use an Auto Enginuity scanner/ diagnostics with the GM module, TOAD and a hand held Autel. I can't lose that code
All grounds checked, entire ignition system checked and fresh plugs, wires components replaced. Plugs look as they should, light tan color, no fouling, arcing etc.
The code has been since I limped this bad boy home. Still comes and goes. No apparent felt misfires, runs and sounds like a new car.
Could it be all because the last few calibration upgrades were never done, from GM? Car ECM?
All replies, appreciated
I use an Auto Enginuity scanner/ diagnostics with the GM module, TOAD and a hand held Autel. I can't lose that code
All grounds checked, entire ignition system checked and fresh plugs, wires components replaced. Plugs look as they should, light tan color, no fouling, arcing etc.
The code has been since I limped this bad boy home. Still comes and goes. No apparent felt misfires, runs and sounds like a new car.
Could it be all because the last few calibration upgrades were never done, from GM? Car ECM?
All replies, appreciated
I use an Auto Enginuity scanner/ diagnostics with the GM module, TOAD and a hand held Autel. I can't lose that code
All grounds checked, entire ignition system checked and fresh plugs, wires components replaced. Plugs look as they should, light tan color, no fouling, arcing etc.
The code has been since I limped this bad boy home. Still comes and goes. No apparent felt misfires, runs and sounds like a new car.
Could it be all because the last few calibration upgrades were never done, from GM? Car ECM?
All replies, appreciated
Depending on when the ecm was updated the last time I don't consider this to be high onthe list.You may want to look up which issues newer calibrations (than yours...) actually do address.
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
Yes, previously, crankshaft sensor OEM installed Crankshaft relearn completed. The calibrations remaining were for emissions and a/c. Two never done last one issued was for 2013 on this 2001 Chevy blazer Ls 4.3L
