So it seemed like over night my power and gas mileage just disapeared. I have an 01 neon 5spd. It was running perfect but now it is really doggy at like 3000rpm. It feels like when you are trying to pass someone when its hotter then hell out and you have your AC on full blast and the ac clutch kicks in and robs all of your horsepower. I thought it was my cai filter so i put a brand new k&n filter on today, and it didnt help one bit, i also replaced the spark plugs. it doesnt sputter, it starts fine, i have no check engine light flashing. What could this be? I dont want to spend a bunch of money on something and have it not have anything to do with my problem. It kinda feels like on my old car when the plug wires went bad... any help would be great!

Thanks

 

Oh and my gas mileage went from an average of 33mpg to about an average of 24mpg!!!!! thats a big difference!

 

Well this would be the time for a date with a scan tool to read live data and look around.

Check you wires over if you have DVOM then it should be like 2-8K Ω.
You scare me with the CEL is not FLASHING, is it ON? If so what codes? (If it does flash you are damaging the CAT).

Then you need to check your TPS vs actual and MAP vs actual. Make sure you are reading the right stuff. MAP will take a baseline snapshot for BARO which your computer uses in it calculations for base fuel map which it then compares to MAP vs TPS for fuel injector PW. SO really need to get under the hood and check things out with a scan tool.

Other than the try some Techron Concentrate from Chevron to help clean out your fuel system and see where you are at.

 

well you may wanna get all your lines for holes...... also take your O2 sensor out and clean it sometimes that helps, you may wanna go around and check that all your wiring harnesses are in right and tightly. I had the same problem with my car i have the same as you im guessing 2001 ES 5spd man, what i did was change the plugs and the wires, if you already changed the plugs, did you change the wires along with that? if not you may wanna try that. how many miles do you have on it btw? if its in the high miles....check the timing belt while your in there... unless you already changed it recently. well try all that and let us know

 

I would say your injectors need to be cleaned out!


Hope this helps!


Mike

 

yes, 2001 es 5spd man, it has 130,000 miles on it, i had the head gasket replaced about 10,000 miles ago, so the timing belt is new, The plug wires only have 15,000 miles on them, i know that they can somtimes go bad even at that amount, i had the codes pulled and there was absolutly nothing, just the one that says, "the battery has been disconected in the last 50 days" which it had. What is the absolute best way to clean the fuel injectors? How can i get the highest concentration of injector cleaner through them? Any other thoughts on this problem would be great.

Thanks

 

I use Valvoline Oil and The Fuel Injector Cleaner. It worked great for the first 1500 miles....



Mike

 

try some seafoam just follow the instructions on the bottle you can buy it at napa