I have a 03 Impala LS 3.8L I swapped out the engine everything runs good but it feels like it misfires or is losing power for alil only when I reach 40-50 mph and the rpm stays around 2000-2500 then it feels like it sputters alil bit, after going over 50mph it’s good and rpm balances out I changed out my spark plugs I just need to change out 2 more but it’s a tight spot behind the engine to get the last 2 spark plugs I had to clean my EGR valve also had carbon in it code came up for that but went off after I cleaned it I don’t know what else it can be if someone can help me it would be very much appreciated and I don’t know if it can be the fuel filter or fuel injectors I think it’s something to do with fuel I don’t think it’s the transmission it’s still new
so I don’t know if I need a new EGR Valve , new fuel pump, injectors, fuel filter, I don’t know if someone can help if they might know what it is would be very much appreciated
forsure I’m gonna change the 2 last spark plugs 😀
it has 163xxx miles but I swapped it out with a 95k miles engine 3800 series 2
We'll always start with the basics first change the fuel filter because a clogged fuel filter will do just that. As well a weak pump doesn't pump enough pressure which you can pressure test but do not pressure test until you change the filter because of the filter is clogged the pressure can be low and it may not be the pump it could be the filter. Also realize if you catalytic converter is clogged up it won't be able to go too fast that can be pressure tested too by removing the oxygen sensor and putting a gauge and seeing how much back pressure exists to see if it's clogged
Ok thank you I appreciate the advice I’ll get the filter hopefully it’s just that. I was wondering if it was the catalytic converter but it barely passed smog 2 months ago. I’ll let you know if I have more questions thanks Scotty 😎
