I added acdelco bg44k in my 2001 pontiac grand prix 3800v6 with 125k miles, on the second day to work, the car started shaking so bad while idling during a red light stop, when I drive there is less of shaking and vibrations, now I have P0300 and P1380 misfire, check engine light comes and goes. I changed my denso spark plug wires, acdelco ignition coils and ICM changed, while spark plugs and engine mounts were changed 9 years ago. Do you guys think bg44k caused engine misfire and shaking?
Engine shaking and misfire after using bg44k.
- Thread starter easym
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Might have dislodged some debris that is now a problem for 1 or more injectors? Did you fire the parts cannon just for this issue?
Has the fuel filter ever been replaced ?
The P1380 is interesting. https://www.ls2.com/boggs/dtcs/DTC P1380.htm
Some info suggests chasing the P0300 first, which made no sense to me if the vehicle is not able to determine if a misfire actually is a misfire.
Finally the link above says:
"Service the ABS system before diagnosing for a misfire, because an actual engine misfire may or may not exist. The following two examples illustrate how this DTC can be set with or without an actual engine misfire"
which makes more sense to me
Some info suggests chasing the P0300 first, which made no sense to me if the vehicle is not able to determine if a misfire actually is a misfire.
Finally the link above says:
"Service the ABS system before diagnosing for a misfire, because an actual engine misfire may or may not exist. The following two examples illustrate how this DTC can be set with or without an actual engine misfire"
which makes more sense to me
I changed the fuel filter 3 years ago.
I think the BG44K dislodged a lot of carbon/deposits and fouled one or more spark plugs. I'd start with the obvious and replace all six plugs with OEM (AC Delco?) plugs or NGK equivalents. 9 years is a long time to go with even Iridium or Platinum spark plugs.
No i haven't changed anything before bg44k everything was fine.
My fuel tank is still full, should I wait until all the fuel+ bg44k mixture to go near empty before changing the plugs?
That's completely up to you, but I would not want to continue driving the Grand Prix with a misfire. Spark plugs are cheap, so personally, I would change them to see if that immediately resolves the problem. You can examine the old plugs once removed and always have the option to remove and clean a new plug if it becomes fouled.
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P0300 you say? You gotta 3800 V6? You need an ICM. I've gone through several over the years. They give you no warning whatsoever.
My latest misfire was from a bad pin in the ICM connector. P0303. I'd go driving along and the engine would shut itself off. Long story short, I had to replace the entire ICM connector. 14 pins on that thing and the replacement connector from ACDelco will have all the 14 wires white. You gotta label your wires before making the splices since the connector doesn't have color coded wires like the factory one did.
My latest misfire was from a bad pin in the ICM connector. P0303. I'd go driving along and the engine would shut itself off. Long story short, I had to replace the entire ICM connector. 14 pins on that thing and the replacement connector from ACDelco will have all the 14 wires white. You gotta label your wires before making the splices since the connector doesn't have color coded wires like the factory one did.
Had a similar problem with a 3.8 in a Buick Le sabre, turned out to be a miss firing coil module. A mechanic friend had a spare module that proved the solution.
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There was one time I had an ICM that would fire 2 out of 3 coil packs. That caused a flashing P0300.
Pull the plugs, clean them off, put them back in, and drive it. Let the BG44 do its work as much as possible. You do want all the plugs firing. Hopefully it’s not an injector, but if something got lodged in one, more time with the chems may keep it going.
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Then it could be the connector going to the ICM like mine was. I had a brand new ICM installed when the engine would shut off like someone reached in and turned the key. The little burnt female pin that had been arcing provided the clue. The computer probably didn't like that one pin arcing and decided to shut the engine off.
Let's back up to the opening post. Why was the ACDelco BG44K added to the fuel system?
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There was a sale in ebay for 3 acdelco bg44k cleaner for $40 , so I thought why not it may help my pontiac grandprix with mpg.
+1 on the fuel filter.
That is what our 2001 Impala did when the fuel filter was clogging up around 100,000 miles.
It also required ignition coils not too long after that. So, I'm thinking it could be either one.
I still find it fascinating everyone wants to ignore the P1380. Wonder what GM guru @clinebarger thinks? Would you chase the 1380 or the 0300 first?
I am sorry for the problem, but why do you put BG44K if the car runs fine? Adding things to fuel tank is mostly to satisfy our ego that we do something good, cleaning, or whatever.
We never need to add anything but a good fuel with enough detergent from top tier gas stations.
P0300 is random misfire, not sure which one or all of them misfire randomly. I would check the wiring first, there is 0 chance all sparkplugs or coils failed. I suspect the fuel system next.
I won't wait until the tank empty for a misfire. The effect is huge from fuel dilution to the engine oil and worse dead catalytic converter from overheating.
GM 3800 is probably the most reliable engine GM ever made. It also has good mpg for V6. If you want better MPG, get a Toyota hybrid that at least as reliable as 3.8L GM instead of wasting money for additives.
We never need to add anything but a good fuel with enough detergent from top tier gas stations.
P0300 is random misfire, not sure which one or all of them misfire randomly. I would check the wiring first, there is 0 chance all sparkplugs or coils failed. I suspect the fuel system next.
I won't wait until the tank empty for a misfire. The effect is huge from fuel dilution to the engine oil and worse dead catalytic converter from overheating.
GM 3800 is probably the most reliable engine GM ever made. It also has good mpg for V6. If you want better MPG, get a Toyota hybrid that at least as reliable as 3.8L GM instead of wasting money for additives.
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