01 z28 six speed Big Hesitation u/Load

**5abivt** · 08-23-2009, 11:10 AM

Half throttle I notice it and sometimes at full throttle.. it feels like it is losing and gaining about 75 hp. sometimes it will feel like its low on power through the whole gear other times it will kick back in and feel good.

I notice when I decelerate as well it slows down smooth and then all of a sudden slows down harder while still coming down in rpms in the same gear. Although I'm guessing this may have something to do with the ecm changing the mixture under decel for emissions etc.

Car has new plugs, wires, batt, alternator. Has a new K&N and free ram air mod. it did this before all these changes too.

I am leaning towards fuel filter or possibly an injector being bad?

**blackSS01** · 08-24-2009, 01:45 AM

Do fuel filter, then go to the store and get MAF cleaner and go ahead and clean that bitch. K&N's can sometimes have TOO much oil on them and it gets on the MAF wires. The spray is made for electrical and will evaporate in seconds. Don't be afraid to spray the wires down 2 or 3 times. Let dry and re-install. If that doesn't work, get back to us.........

**5abivt** · 08-24-2009, 07:59 AM

I'll give that a try. Only thing is it did this before I did the K&N swap. I plan n changing to a diff brand filter I'll just do that at the same time. I live in a new area with a lo of construction. Knowing how bad the K&Ns are makes me nervous with all this dust. thanks for the input !

**0rion** · 08-25-2009, 10:29 AM

sounds like you're on the right track......it sounds like a spark or fuel issue and since you've taken care of the spark side it's time to start looking at the fuel side. Do like blackss01 said and swap that fuel filter and clean your MAF and see what that gets you.

**5abivt** · 08-26-2009, 03:24 PM

Thanks for the input. Going to get to the filter in between zaino coats tomorrow. I never thought to notice it all the times ive been under there, can anyone tell me where it is? just bein lazy

**0rion** · 08-26-2009, 03:44 PM

drivers side frame rail just in front of the axle

**5abivt** · 08-28-2009, 06:15 PM

Thanks Orion. Can anyone tell me what size wrenches or if theres anything fancy to get it off? I was too lazy to even look I barely finished putting on the z2 polish before work which sucks because its already raining while in im here

Im a little worried because I don't think its ever been done and the car is over 200k km. I dont want to twist a fuel line since itll probably be rusted. the car was driven through our winters every year.

**blackSS01** · 08-31-2009, 11:29 PM

I don't know off hand the size but just do a google search. If its original then I have money on that being the culprit, suppose to change them 1 time a year or every 12,000 miles