sooo this is bugging me.. a lot.

[nsaniti]

build is a forged 306 bottom end, gt40p heads, tubular gt40 intake, cam, vortech v1 on 10lbs. I barely drive the car, and its running old school on 24lb injectors and an fmu, recently got off the highway and all of a sudden feels like I lost a cylinder.

I have a bad low rpm miss, and it doesnt pull nearly as strong up top, however it does smooth out a bit. TPS voltage is normal, fuel pressure is good, timing is good, and no vacuum leaks. Only thing I have noticed since it began running like it this is a TINY oil leak.

Changed cap and rotor, but keep in mind it must be things that couldve possibly changed in an instance when I got off the highway and began accelerating. Feels like a blown headgasket, but theres no smoke, no over heating, and no mixing of oil/coolant.

Shoot away lol.

Thanks :]

[03z06vette]

Plugs

[nsaniti]

are clean. next?

[03z06vette]

compression or plug wires

[Gearhead]

TFI module or distributor check out ok ?? Balancer hasn't spun ?? Good fuel pressure ?? Fresh fuel filter etc ??

[Kevin1989]

i told you to try a TFI matt wont hurt nothing to try.

[graysonracin]

burnt plug wire, or distibutor issue, coil, injector, maybe?

[nsaniti]

wires are fairly new, but have a life time warranty so i suppose it wouldnt hurt to check those. changed out my msd coil to a new one. i have yet to check TFI, im just trying to eliminate possibilities. like i said it was running nuts on until i got off the highway, accelerated from a light and it turned into shit. and yes i stated in the original post the fuel pressure is fine and climbs like normal in boost. I'm going to try to track down a TFI module from a friend instead of buying one without knowing for sure, and next is compression and leakdown tests.. idk what else to do. its about time to tear into a decently fresh build =\

[kennebellcobra]

I would do a leak down...sounds like it could have burnt a piston.

[nsaniti]

I would do a leak down...sounds like it could have burnt a piston.

im definitely going to as soon as i have some free time after the holidays. the fact that its so streetable still other than the low rpm miss just throws me off. hopefully leakdown/compression testing shows something i havent found yet..well part of me still wishes it wouldnt lol. :lol:

[evil8]

Check to see if its an LS1, if not, remove and replace.

[nsaniti]

Check to see if its an LS1, if not, remove and replace.

lol sure thing.

as far as TFI goes, ive only heard of this being good or bad.. and if theyre bad they usually just cause your car to die when hot..right? this is annoying the hell out of me.

[ibstrokin]

Check the plug wires with an ohm meter, there should be a given resistance per foot. If you have a wire that is way above the norm, the ohm meter will tell you, you can't always trust a visual inspection.

[5.0calypso93lx]

I would start out by finding if it does have a dead cylinder. That way if you do, you can trouble shoot that one cylinder. Start unplugging injectors one by one. The idle should drop each time you unplug one. If it doesn't, you'll know which cylinder is the dead cylinder.

[NXcoupe]

lol sure thing.

as far as TFI goes, ive only heard of this being good or bad.. and if theyre bad they usually just cause your car to die when hot..right? this is annoying the hell out of me.

Just do a quick compression test and be done with it. Unless you're just bored and want to have something to talk about on the internet. If it's not plugs it's a bad wire, if it's not a bad wire, it could be a faulty distributor which is easily checked by swapping it out, and if not that then it's probably a blown head gasket or a piston. Misses on any kind of power adder car after a brief period of boost will usually indicate something has given up under the strain. jmho.

[facemelter71]

Just do a quick compression test and be done with it. Unless you're just bored and want to have something to talk about on the internet. If it's not plugs it's a bad wire, if it's not a bad wire, it could be a faulty distributor which is easily checked by swapping it out, and if not that then it's probably a blown head gasket or a piston. Misses on any kind of power adder car after a brief period of boost will usually indicate something has given up under the strain. jmho.

He works,ALOT.Twice as much as I do.Im tryin to help him along,Im sure as soon as he is able to perform a comp test,he will. Just with him working so much and it being his DD,he's kinda hurting for time to work on it.

[nsaniti]

He works,ALOT.Twice as much as I do.Im tryin to help him along,Im sure as soon as he is able to perform a comp test,he will. Just with him working so much and it being his DD,he's kinda hurting for time to work on it.

spot on lol.. 84+ hrs a week will get in the way of spending too much time working on it. its been sitting in the garage for a month now, luckily the girl has been willing to deal with driving me to work lol. changed the dizzy and tfi today.. small improvement but no dice. probably going to check into a new MAF next, as I have a feeling my proflow may have shitted out on me. and on that note, if anyone has any suggestions of what 24# MAFs go okay with boost, let me know.

[2Kblacksleeper]

Off topic .....

I will give you a call later today.

J ohn

[Kevin1989]

correct me if im wrong... but if you unplug your maf and the maf is indeed the issue wouldnt it run better? i dont know what it would do with a power adder car.

[facemelter71]

Mine would run like ass if I unplugged it. Like an idiot I clocked it different one day to adjust for a change in my intake length and it ran like shit. And that is just from turning it clockwise.Luckily I found the spot where it was tuned in,and left it.

[nsaniti]

I had actually already had the same thought kevin, but with the blower as soon as you get into the throttle at all the car literally shuts off.. It will run just fine with it unplugged though, as long as you are easy on the throttle. I have a friend sending me a 70mm cobra MAF calibrated for 24lb injectors, so we will see if thats what it is. If not when I get more free time after the holidays and everything calms down, first thing on my agenda is a leakdown/compression test.

[facemelter71]

Will you be back in town some time soon?

[nsaniti]

LOL soon as in while its still arctic temps? no. I may fly up for a bit sometime though, text me Im curious as to what you have in mind..