Keysplayr

I know it used to have more nuts than it does now. Granted, I just turned 80,000 miles, but I have always used Mobil 1 fully synthetic since first oil change. And, I don't beat the snot out of the car. It just feels like it is being held back.

I changed the plugs at around 68000 miles, have a clean air filter, and always use 93 octane fuels. Would a fuel filter cause such a power loss? The car still has decent power, but I am not rammed back into the seat like I used to be.

Sort of like the timing is retarded on an older disty cap car.

Any thoughts? I have no warning lights on the dash or anything. Something I am overlooking that is very common for you guys?

Thanks in advance for any help.

Keys

LS1_TA_2002

Yep.

Try one of these first (if your budget allows) so you don't re-dirty your filter. It works good with number one because you depressurize your fuel system first which is always a good thing when changing your fuel filter.

1. http://iecoklahoma.com/injclnkit.aspx
Higher initial cost, but best way to clean injectors.
Plus you can charge all of your buddies and relatives a couple of bucks to do theirs (they buy the cans of course) until it pays for itself.

2.https://ls1tech.com/forums/general-maintenance-repairs/534376-how-seafoam-your-car.html
A little more work, but highly effective at cleaning everything else

LS1_TA_2002

P.S. A lot more things could cause this i.e. plugged cats, slipping clutch if you have a manual trans. Try to be more specific about the problem. When does it happen? Hot or cold running engine, under heavy accel, light thottle etc...

Keysplayr

Thanks for the reply!
To be as specific as I can:

The clutch is fairly new and has about 10,000 miles on it. I detect no slipping or any clutch smell/chatter. Seems to grab fully. At that time I also changed the master and slave cylinders. Really had zero probs with clutch installation.

My cats (2 of them) were changed under warranty about 3 years ago as they said they were defective.

When this happens:

Ok, best example I can give is, when I let up just a touch on the throttle from WOT, I noted a "very slight" increase in "pull". First thing that came to mind was air/fuel mixture not correct at WOT and if there is a throttle position sensor, maybe it is screwed up. Second thought was a slipping clutch, but felt nothing like a slipping clutch and no burning smell at all even after I stop the car and stick my nose right in the engine compartment. I wish I could be more specific. I thought maybe I should bring my car to a dealer (my friend is the underwriter there) and have it hooked up to get a diagnostic and see if there is anything going on.

Thanks again for your help!!

bjamick

iTrader: (31)

Have you ever sea foamed your car? https://ls1tech.com/forums/showthread.php?t=534376
Heres a write up if you haven't .
May be just a clogged injector, fuel filter, a number of things. Just do some simple steps first like a nice sea foaming.

Then do a tune up like plugs, wires, cleaning of air filter/ new one, oil change, and check the plugs for a lean/rich mixture, spray you MAF with some brake cleaner so your computer isnt getting mixed signal from it and throwing fuel at it or taking fuel away .

Good thing about those steps is that they are cheap or free

Make sure and let us know if any of this helps.

Spink

iTrader: (1)

The symptom you have could definitely be a fuel filter. My GN was doing that and my brother casually asked me if I changed the fuel filter, I said no and didn't think much of it. I proceeded to do evreything else including a turbo swap, new boost controller, plugs, wires, and more. As a last resort I took 15 minutes to swap the fuel filter that my brother said to do when I first noticed the let of the gas and go faster symptom and it was like I gained 150 HP.

Now I always do that as regular maintenance, every 15K.

Keysplayr

Thanks guys! I just saw you had the same symptom. I am going to change the fuel filter right now. I'll post back and let you know all the horsepower I get back!! :::crosses fingers:::

96slow6

Like someone said up there. If the fuel filter doesnt help like you hope. Be sure to clean the maf. Then if it still seems alittle off, Awnser this for me. Have you ever changed the o2 sensors? I didnt see it posted that you have or did. If i missed it im sorry. 80,000 isnt extreme but i would be willing to bet it would help pick your girl up some.

Keysplayr

Ok, I changed the fuel filter. One thing I noted is that after I started her up for the first time with the new filter, there was a bit of smoke from the tailpipes. Didn't last very long, but it was there. As for any major difference? Not really much on the first drive, but 2 or three startups later, I noticed a little bit faster throttle response and a slight bit more pull at WOT. Nothing to write home about though.

I will try cleaning the MAF. And no, I have never changed the o2 sensors. I will clean the MAF and try that first. o2 sensors are not cheap, so I am hoping they are ok. Once again, there is no check engine light on. I would hope that if the o2's are bad, that light would come on. ??

Thanks again for all the help.

Keys

96slow6

Your o2's have a very wide range and are horribly imprecise. The older they get the worse it gets. Im with you, i hope the maf brings you back up to what you consider par. But if not, and you have had a mpg decrease a new set of o2's might just put that kick be in her.