Sounds like the OP is not getting the answers he wants and no one is agreeing with his solution to the problem that he already knows the answer to.
Almost? So, not the same
You say only if you exceed 3400 rpm. Which you only do intermittently, so it is intermittent.
Simple don’t go over that and all will be well.
Just what sing? Is it a tune we would know?
What nucleus trained you? Did it teach you to troubleshoot ? Do you even read what you write?
I would replace all the spark plugs just for giggles.
Just as an aside from what I’ve read here I wouldn’t want you troubleshooting a burnt out light bulb.
The basic premise in troubleshoot is to eliminate what the problem cannot be. If it were plugs their degradation would be seen full time. If it were a single plug or a few those cylinders would show up in the trouble codes. They don’t.
My methodology to determine problems requires skills that are second to none, and I’m paid handsomely for it. We can’t just throw anything and everything at a problem (which most mechanics do). We are by nature and LAW required to be able to CLEARLY define a problem as best as possible to the highest degree possible. If we make mistakes or come to wrong conclusions THE FIRST TIME things can go very wrong VERY fast (think China Syndrome for those old enough to remember that). This requires careful examination of THE FACTS, which I have not found in any replies, yours included pvt. When I troubleshoot it keeps that light burning so even you could see if it’s burned out, and I rarely fail, that’s why I’ve been doing it for over 40 years, and I have the certifications to prove it.
Boy this went bad fast!
I had a very similar issue with a Ford a few years back. Same scenario heavy load with 3/4+ throttle brief light flash and no other problems. The problem was a dirty MAF sensor. Just my two cents.
thank you fleet, that was the type of thing I was looking for.
For what it’s worth…
A friend of mine has a 2003 Chevy pickup with almost the exact same issues you’re describing. He’s spent a small fortune at various mechanics (both dealer and independent) over the years; none of them have been able to “fix” the problem. He’s learned to live with it.
I’m not saying that you should go the same route. Just sharing my experience.
And that is exactly what I was hoping to avoid. I’ve read quite a few posts about those kinds of nightmares. thank you.
and do you do this diagnosing online? And talking with a person that won’t believe what you are telling them?
they never really told me anything.
fleet! Thank you, just what the doctor ordered. Total cost 9 bucks for the sensor cleaning spray. 18 bucks to replace the air filter that was supposed to have been changed 20K ago. I usually mark a filter that has been replaced for just this reason but didn’t do it last time because of family stuff occurring around that time. I’ll never miss that again. I’ll never use that oil change service again.
Total cost under 30 bucks. A far cry from what the dealer was saying. they wanted to do a maint package that ran 900 bucks, and DIDN’T include cleaning the MAF as far as I could tell.
Well then, as a trained automotive diagnostics expert, I will say that I don’t guess at problems. I diagnose them.
P0300 is a general fault code for cylinder misfire. It does not mean that all the cylinders are misfiring. Some vehicle manufacturers do not generate the P0301 through P0308 codes, they simply generate a misfire code and have you determine which cylinder is it.
Of which you have given us none. Please post the “Freeze Frame” data from your car’s memory. This is a snapshot of general engine data at the moment the fault that triggered the check engine light happened. This is vital, for what I think are obvious reasons.
So after reading all powertrain codes, use your scan tool to access your live data cylinder contribution test and determine which cylinders are misfiring under what circumstances, i.e. at idle, at wide open throttle, and note the fuel trim numbers to determine if the fault is ignition, mechanical, or fuel related. Misfires will be logged as either current or history.
An under-reporting Mass Air Flow sensor should have been found from the driver’s seat, using a scan tool, without even opening the hood. It’s unfortunate that the dealer you saw did not have a technician able to properly diagnose your problem quickly. Sadly, there seems to be a shortage of service shops, both dealer and independent, that are willing to pay handsomely for quality work.
I understand how difficult it is for a customer with a broken car to find a shop they can trust.
Actually I gave all the facts I had at the time. My car will give failure codes on a per cylinder basis. The OBD reader I borrowed did not have a gamut of info, but in this particular case most of that probably would not have made much difference since there was only one code. The MAF readings at idle did not vary much from the normal specs. I’ve come to find in review two things were at play. Normal maint 20K earlier should have put a new air filter in. I paid for it but it wasn’t installed, that’s another matter BUT it did contribute to the actual problem since airflow was restricted somewhat. At lower RPMs this would not have been seen as much as a sudden acceleration when both fuel and air demand are increasing rapidly. Also at lower RPMs the differential between measured airflow and actual airflow is greater since errors in the detector are squared as the velocity increases. Therefore errors at 4000 RPM are 4 times higher than the errors at 2000 RPM. Since this happened I’ve done a wider search than just my car and my engine on google. This particular problem has shown up in a great many searches with the exact same or almost same indicators. I would assume that seeing the number of YouTube videos about cleaning the MAF and the fact that a specific cleaner for MAF sensors is sold at all auto parts dealers that those who are familiar with it would be greater in number. Luckily for me there was at least one.
Glad you fixed it!!
Thanks to you!
Clogged fuel filter or maybe the filter on the fuel pump.