bigchevyman24

iTrader: (2)

Hey guys,

I am starting to have a bad miss around 5k rpms...I'm going to check the plug wires tomorrow. I just installed long tubes, but I don't think it was from them as I noticed a slight miss before the install. Now, when it hits 5k rpm at WOT, it starts spitting and sputtering. It also feels like I have a small miss going through the gears at about 1/2 throttle above 2500 rpms. I can't really tell, but it just doesn't feel quite like it's pulling 100%. Could this be from the egr/air delete(I actually didn't delete anything, just plugged the lines) or from the K&N intake I also put on? Any ideas or suggestions are welcome. Thanks alot!!!

the_merv

iTrader: (88)

Do the ICM spacer mod and upgrade the Coil.

BlackScreaminMachine

iTrader: (17)

Check your Fuel Pressure @ WOT, which means hook a guage up, tape to windsheild and to a blast or 2 some where safe.

LaVy

iTrader: (5)

Sounds to me that opti spark needs replaced

bigchevyman24

iTrader: (2)

I was afraid it may be the opti-spark. I'm probably gonna try whichever is cheapest first between the coil and opti. I checked today and it looks like I have a plug wire close to the headers on the drivers side. I'm gonna get some shielding for it and see if it helps. I'm sure it's something else, though as I was developing the miss before the headers. I may do the plug wire re-routing and get new wires. Any suggestions? Thanks

86formula

iTrader: (3)

Having the same problem, ICM did nothing, ill let you know what fixes it because i have a new coil and opti sitting in my room

mj114679

i got the same problem.... i just get the run around when i talk to people.... but dont listen to the guys that say delete the cat... i did it and didnt fix anything. i also replaced my tranny thinking its the problem.. but it wasnt... i got a very nice car that cant hit 5k rpm... so PLEASE LMK how this goes

bigchevyman24

iTrader: (2)

I guess I'm gonna do a good tuneup on it. I have 158k miles so I'm sure it's due. Gonna try plugs, wires(relocate too), fuel filter, and probably get a new coil and opti. Might replace the water pump while I have it off if I can find one on the cheap side. Let me know if the coil and opti help you out! If anyone else has any other suggestions or where to get these parts cheap please post. thanks

enjoi355

iTrader: (3)

whats the icm spacer mod??

the_merv

iTrader: (88)

When you re-bolt the ICM and the Coil..bolt the ICM on the outside of the first set of nuts instead of directly against the Head.

bigchevyman24

iTrader: (2)

Ordered an msd coil. Gonna see what it's gonna do. Then do the plugs and wires...Gonna space the coil from the head too...hope it helps as it seems to be getting worse at WOT...

enjoi355

iTrader: (3)

what does that do??

the_merv

iTrader: (88)

Keeps it cool so it works better. Heat from the Head makes it get really hot and the internal components lose conductivity.

ss.slp.ls1

iTrader: (36)

Sounds like a good plan of action. Don't forget to check your fuel pressure at 5k rpm WOT under load. I had a bad miss at 5k rpm and I hooked up a gauge and drove it around and watched as my fuel pressur dipped to about 20psi when the miss occured. I replaced the fuel pump with a Racetronix kit and all was well. Until my opti went out a few weeks later. Swapped on a new one from "thepartsladi" and made sure to thread lock the rotor screws, threw in some new plugs and wires to boot, and I've been problem free for almost 30k miles now.

You can get a new opti from "thepartsladi" on ebay.
I'd get a new GM coil, NGK TR55 spark plugs, and MSD wires.
Water pump shouldn't be too much, I see it for 223.29 from GMPartsDirect. You might be able to find it cheaper, I don't know where though.

bigchevyman24

iTrader: (2)

Where is the fuel filter and fuel pump on these cars? I hope not in the tank. I absolutely hated replacing the intake pump on my old Tahoe.

Where and how should I go about the fuel pressure test? What is normal pressure throughout the rpm range? What do I need to perform the test? Thanks

ss.slp.ls1

iTrader: (36)

Yes, it's an in-tank pump. You can cut an access panel like I did. Makes pump changes a breeze.

Hook up a fuel pressure gauge to the schrader valve on your fuel rail.
http://shbox.com/1/fuel_schrader_valve.jpg
Disconnect the vacuum line to your fuel pressure regulator. Start the car. Fuel pressure spec is 43.5 psi, but anywhere from 41-47 psi is normal. Slip the gauge under the top of the hood and close the hood while keeping the gauge visible from inside the car. Now take the car for a spin and watch the pressue as you get to upper rpm's under load. It should hold strong, if not, you might need a new fuel pump.

The fuel filter is located under the car near the driver side rear tire. Get the car up in the air and slide under there and you should see it.

bigchevyman24

iTrader: (2)

thanks. I'll update the thread when and if I find the problem.

blkcamaro_z28

iTrader: (3)

Had that problem last year and it ended up being my Fuel Pump and AC Delco aren't cheap either. Fixed all my problems and then 3 weeks ago got that miss again and had my fuel pressure checked and it was fine, ended up being those junky Bosch plugs that I put in it, so I replaced with AC Delco plugs and now she's purrrring again. Another thing is that if you put on the K&N CAI the MAF doesn't wanna go all the way into the fitting sometimes and will leak air and cause a miss and check engine light will come on but that doesn't sound to be the case for you. Just my 2 cents. Hope this helps.

86formula

iTrader: (3)

mine has a new pump, new filter, and new injectors. the coil and opti should be going in today, ill keep you guys posted

myltwon

iTrader: (1)

I'd pop the hood at night and look for arching, free and easy test