please help.....have a constant miss over 5K, please read, i cant figure it out....
Registered User
Joined: May 2002
Posts: 87
From: ARNOLD MO USA
i have ran without my maf no help.
never tried aftermarket /larger maf but have swapped in new delco and no help see my post a page or two ago. ive replaced about 20 different parts and still no help.
i had my head and intake off because i had to pull the rt side head because a manifold stud broke off and i had to have it drilled out?? after i reassembled the engine is when my prob started idid a tune up while i had the engine apart but thats not it either i since then have replaced all wires and plugs twice. in 10000 miles. but it could be electrical i did have (EVERYTHING) unplugged i havent checked opti wire harness yet.
im running factory stat.
brad i think we have same mods.
borla catback.
k&n cai
vortech ss/elbow
msd coil
msd wires
delco plat plugs.
thats it.
ive often wondered about msd ignition box also.
lets keep it going guys were bound to nail this!!!!!!!!!!!!1
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94 T/A LT1 A4
SOME MODS,KINDA QUICK
times- C-YA AT THE TRACK!!
never tried aftermarket /larger maf but have swapped in new delco and no help see my post a page or two ago. ive replaced about 20 different parts and still no help.
i had my head and intake off because i had to pull the rt side head because a manifold stud broke off and i had to have it drilled out?? after i reassembled the engine is when my prob started idid a tune up while i had the engine apart but thats not it either i since then have replaced all wires and plugs twice. in 10000 miles. but it could be electrical i did have (EVERYTHING) unplugged i havent checked opti wire harness yet.
im running factory stat.
brad i think we have same mods.
borla catback.
k&n cai
vortech ss/elbow
msd coil
msd wires
delco plat plugs.
thats it.
ive often wondered about msd ignition box also.
lets keep it going guys were bound to nail this!!!!!!!!!!!!1
------------------
94 T/A LT1 A4
SOME MODS,KINDA QUICK
times- C-YA AT THE TRACK!!
Registered User
Joined: Aug 2002
Posts: 39
From: Forked River, New Jersey USA
I have an msd 6AL. Car used to run fine till I got the bogging at ALL rpms problem. At this point I wish it was just missing after 5100. Better than bogging and stumbling at all rpms. 
Registered User
Joined: Jul 2002
Posts: 131
From: Northern VA
ok...results of my "test" drive home...now I'm REALLY F*(king confused.
in open loop (and below 200 degrees) no problem, run up to 6k rpm...but the it boggs (more likely rev. limiter right?)
in closed loop and below 200 degrees, no problem, runs up to 6k...except once when it bogged at 5100.
in closed loop and above 200 degrees, problems from start at 5100 in 1st and 2nd. HOWEVER, if I slow to a roll, downshift to 1st and floor it, up to 6k. Same thing in 2nd.
Could you guys go out and try a couple different things like i did? would be interested to see the results.
How about running the cars in open loop all the time? is that dangerous?
It seems to me that the symptoms are WAYYYYY to eratic...WTF???
Cheers,
-MJ
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MJ - 1995 z28 M6
Eibach Lowering Springs, KYB Shocks, K & N Filter Kit, Borla Exhaust, Ground Effects.
in open loop (and below 200 degrees) no problem, run up to 6k rpm...but the it boggs (more likely rev. limiter right?)
in closed loop and below 200 degrees, no problem, runs up to 6k...except once when it bogged at 5100.
in closed loop and above 200 degrees, problems from start at 5100 in 1st and 2nd. HOWEVER, if I slow to a roll, downshift to 1st and floor it, up to 6k. Same thing in 2nd.
Could you guys go out and try a couple different things like i did? would be interested to see the results.
How about running the cars in open loop all the time? is that dangerous?
It seems to me that the symptoms are WAYYYYY to eratic...WTF???
Cheers,
-MJ
------------------
MJ - 1995 z28 M6
Eibach Lowering Springs, KYB Shocks, K & N Filter Kit, Borla Exhaust, Ground Effects.
Registered User
Joined: May 2002
Posts: 87
From: ARNOLD MO USA
im right there with ya anything over 200 degrees and it misses except this morning it missed in and out of c loop. WTF?? is right
and i dont have any edit or scan equip.
this weekend is a club run at a local st louis track, and a guy is going to plug into it and see what he finds???
and i dont have any edit or scan equip.
this weekend is a club run at a local st louis track, and a guy is going to plug into it and see what he finds???
Registered User
Joined: Jul 2002
Posts: 131
From: Northern VA
heath,
hope that sheds some light on this situation....I'm geared to computer probs...it's tooooo damn sporatic (sp?) to be a mechanical problem.
Heath, take a ride and try a couple things if you don't mind...let us know what the resutls are.
Cheers,
-MJ
hope that sheds some light on this situation....I'm geared to computer probs...it's tooooo damn sporatic (sp?) to be a mechanical problem.
Heath, take a ride and try a couple things if you don't mind...let us know what the resutls are.
Cheers,
-MJ
Registered User
Joined: May 2002
Posts: 87
From: ARNOLD MO USA
i cant right now im at work and dont have net at home yet.
my car rev it its fine!
slowly drive it in 1st up to 6000 its fine!
*punch it dead stop starts fluttering at 5100
sometimes slowly climbs thrue it while fluttering up to 6000 and then shifts.
cruise under 40 or so and punch it it kicks down to 1st and hauls *** till it hits 5100 then same thing.
cruise at 70 punch it kicks down to 2nd and imediately hits 5100 and starts it again.
my car will do it every gear.
it does seam more sluggish since this problem arrived.
less response off Idle launch.
used too the car would spin all the time.
(THE FASTER YOU PUNCHED THE PEDDLE THE MORE THE TIRES WOULD BREAK LOSE LIKE YOU SUPRISED IT!
now you punch it and it starts rolling into it and then hits about 1900 rpms and the tires start to spin alittle and then it goes like a bat out of hell until 5100.
so im screwed any way you look at it.
hows that compare to everyones testdrive experience
my car rev it its fine!
slowly drive it in 1st up to 6000 its fine!
*punch it dead stop starts fluttering at 5100
sometimes slowly climbs thrue it while fluttering up to 6000 and then shifts.
cruise under 40 or so and punch it it kicks down to 1st and hauls *** till it hits 5100 then same thing.
cruise at 70 punch it kicks down to 2nd and imediately hits 5100 and starts it again.
my car will do it every gear.
it does seam more sluggish since this problem arrived.
less response off Idle launch.
used too the car would spin all the time.
(THE FASTER YOU PUNCHED THE PEDDLE THE MORE THE TIRES WOULD BREAK LOSE LIKE YOU SUPRISED IT!
now you punch it and it starts rolling into it and then hits about 1900 rpms and the tires start to spin alittle and then it goes like a bat out of hell until 5100.
so im screwed any way you look at it.
hows that compare to everyones testdrive experience
Thread Starter
Registered User
Joined: Sep 2001
Posts: 903
From: boxboro, MA, USA
i had a granatelli MAS and it did sh*t, dont waste your money. i just ordered MSD OTVC wires and have some AC Delco plugs waiting to go in.......will keep you posted. if this dont work, its opti swap time again....
brian
brian
Registered User
Joined: Aug 2002
Posts: 84
From: St. Louis, MO
well ****...... maybe it is intake to head leaks..... i think i heard someone say that already... is there a TSB for torque sequence or specs on the intake. how many people with this problem have had their intake off before? since they notoriously do not seal well, maybe we are getting heavy vacuum leaks at high rpm's when the cylinders are pulling a lot of air?
Rob
Rob
Registered User
Joined: Jul 2002
Posts: 131
From: Northern VA
rob,heath,sleeper,
I'm having EXACTLY the symptoms as heath...except for sluggish off the line...I can't really say..haven't owned the car since the begining and I've never had the opportunity to drive another z.
I have phantom a/f and vacuum guage. a/f read rich when I floor it once I reach about 4k rpm, and the vacuum guage reads 0 all the way through. BTW: it reads 20 on the nose and steady at idle. And I'm not really sure about the reliability of the guages.
Anyone try fuel pump or injectors yet.
Maybe our answer lies in the fact the when we inch it up to 5100 it's cool...but when we go WOT we got probs.
Someone get a GM tech on the line!!!
Cheers,
-MJ
------------------
MJ - 1995 z28 M6
Eibach Lowering Springs, KYB Shocks, K & N Filter Kit, Borla Exhaust, Ground Effects.
I'm having EXACTLY the symptoms as heath...except for sluggish off the line...I can't really say..haven't owned the car since the begining and I've never had the opportunity to drive another z.
I have phantom a/f and vacuum guage. a/f read rich when I floor it once I reach about 4k rpm, and the vacuum guage reads 0 all the way through. BTW: it reads 20 on the nose and steady at idle. And I'm not really sure about the reliability of the guages.
Anyone try fuel pump or injectors yet.
Maybe our answer lies in the fact the when we inch it up to 5100 it's cool...but when we go WOT we got probs.
Someone get a GM tech on the line!!!
Cheers,
-MJ
------------------
MJ - 1995 z28 M6
Eibach Lowering Springs, KYB Shocks, K & N Filter Kit, Borla Exhaust, Ground Effects.
Registered User
Joined: Sep 1998
Posts: 1
From: MT.VERNON,IL
Ok guys,this might help. I have the same miss & lack of power, but with a little different setup. I have a '95Z. Rebuilt bottom end, headwork, ported intake, tb, exhaust, etc. With a F.A.S.T. computer and wide-band O2. I do not have a MAF sensor, speed density now. I do not have any factory emissions equipment either. I have a FP gauge mounted underneath the 4" cowl, so I constantly monitor the FP. I have been chasing this for about a year now. I have replaced: Opti 3 times, plugs 3 times, wires twice, coil twice, ignition module, MAP, harness for Opti, checked wiring harness, grounds, checked rockers. I can monitor the data while driving and data log times, but nothing shows up to be the cause. Hopes this maybe eliminate some things.
tom
[This message has been edited by BLOWN LT1 (edited August 22, 2002).]
tom
[This message has been edited by BLOWN LT1 (edited August 22, 2002).]
Registered User
Joined: Feb 2002
Posts: 33
From: federalsburg, Md USA
i know this may not help, and seeing how far you all have gone into this......
i fought this problem for a good year.... anything over 5g's would back fire like revlimiter let off of her some it would pull on through... but like you said in neutral it doesnt do it, (no load on engine) but in gear... popped like a fire cracker... i cahnged coil, wires, plugs, and it cured it.. but i dont think that was it... cuase now i have an ocasional slight stumble, or more orless hesitation, on hot *** days.. my car never gets over 180-190 degree's on a hot day, maybe 200 at max but not very often. and here the days will be 95 heat index of 105.. and thats when i notice it.... if its cool, it will break ur neck shiftin.. it p*** me off... i am gonna start relocating stuff and see what hapens...
oh and i have had my car down to the bare block.... there is a sequence of torquing the intake that needs to be used... i think some one asked about that ....
what i did notice about the wires that even the slightest mark on them can totally mess em up.... i did notice that some times the wires would seem to be on the opti all the way but be barely conecting to it.. any one runnin the over the top wires and made for you wire looms? have ya had these problems?
like i said probably doesnt help any but this is what i did to get my z runnin again,
and no computer that was plugged into her could help... i unplugged air sensors, maf, guted some things... changed some sensors switched em back and forth.... some one mentioned the fact of to much air, and theres happened after the maf screen was out.. My car was totally stock when it started to miss or what ever ya wanna call it.. now is been tweeked to the best of its abilities, and it has some what fixed it..with out buyin all kinds of aftermarket stuff. so i think it is something to do with heat wether it be hot air, hot coil/ electronics, maybe even to lean / rich. i know what i have written probably helps no one, but i just wanted to say what i have tried, any more ??'s just ask
-j-
------------------
Silver, 95Z, A4, 3.23's, homemade CAI, TB bypass, MAF screen, boot converted to a 1LE style, borla catback, gutted cat, upgraded coil, HPP III, 160 thermo, 8.8 mm wires, numerous tires, and 9 spark plugs (guess dealership thought i didnt need that 8th one till later
Fast enough to beat an '01 gt
i fought this problem for a good year.... anything over 5g's would back fire like revlimiter let off of her some it would pull on through... but like you said in neutral it doesnt do it, (no load on engine) but in gear... popped like a fire cracker... i cahnged coil, wires, plugs, and it cured it.. but i dont think that was it... cuase now i have an ocasional slight stumble, or more orless hesitation, on hot *** days.. my car never gets over 180-190 degree's on a hot day, maybe 200 at max but not very often. and here the days will be 95 heat index of 105.. and thats when i notice it.... if its cool, it will break ur neck shiftin.. it p*** me off... i am gonna start relocating stuff and see what hapens...
oh and i have had my car down to the bare block.... there is a sequence of torquing the intake that needs to be used... i think some one asked about that ....
what i did notice about the wires that even the slightest mark on them can totally mess em up.... i did notice that some times the wires would seem to be on the opti all the way but be barely conecting to it.. any one runnin the over the top wires and made for you wire looms? have ya had these problems?
like i said probably doesnt help any but this is what i did to get my z runnin again,
and no computer that was plugged into her could help... i unplugged air sensors, maf, guted some things... changed some sensors switched em back and forth.... some one mentioned the fact of to much air, and theres happened after the maf screen was out.. My car was totally stock when it started to miss or what ever ya wanna call it.. now is been tweeked to the best of its abilities, and it has some what fixed it..with out buyin all kinds of aftermarket stuff. so i think it is something to do with heat wether it be hot air, hot coil/ electronics, maybe even to lean / rich. i know what i have written probably helps no one, but i just wanted to say what i have tried, any more ??'s just ask
-j-
------------------
Silver, 95Z, A4, 3.23's, homemade CAI, TB bypass, MAF screen, boot converted to a 1LE style, borla catback, gutted cat, upgraded coil, HPP III, 160 thermo, 8.8 mm wires, numerous tires, and 9 spark plugs (guess dealership thought i didnt need that 8th one till later
Fast enough to beat an '01 gt
Registered User
Joined: Jan 2001
Posts: 108
From: Fremont, CA
<font face="Verdana, Arial" size="2">Originally posted by MJ_Z28:
ok...results of my "test" drive home...now I'm REALLY F*(king confused.
in open loop (and below 200 degrees) no problem, run up to 6k rpm...but the it boggs (more likely rev. limiter right?)
in closed loop and below 200 degrees, no problem, runs up to 6k...except once when it bogged at 5100.
in closed loop and above 200 degrees, problems from start at 5100 in 1st and 2nd. HOWEVER, if I slow to a roll, downshift to 1st and floor it, up to 6k. Same thing in 2nd.
Could you guys go out and try a couple different things like i did? would be interested to see the results.
How about running the cars in open loop all the time? is that dangerous?
It seems to me that the symptoms are WAYYYYY to eratic...WTF???
Cheers,
-MJ
</font>
ok...results of my "test" drive home...now I'm REALLY F*(king confused.
in open loop (and below 200 degrees) no problem, run up to 6k rpm...but the it boggs (more likely rev. limiter right?)
in closed loop and below 200 degrees, no problem, runs up to 6k...except once when it bogged at 5100.
in closed loop and above 200 degrees, problems from start at 5100 in 1st and 2nd. HOWEVER, if I slow to a roll, downshift to 1st and floor it, up to 6k. Same thing in 2nd.
Could you guys go out and try a couple different things like i did? would be interested to see the results.
How about running the cars in open loop all the time? is that dangerous?
It seems to me that the symptoms are WAYYYYY to eratic...WTF???
Cheers,
-MJ
</font>
Later,Brian
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Black 1994 Z28, M6 conversion complete. Eibach Pro-kit, Bilstiens, Chrome 17x11 ZR1 rims, LS1 Brake Upgrade, K&N CAI, AS&M Headers, High-flow Cat, B&B Tri-Flo W/ Quad Tips, Cutout, B&M Ripper, McLeod Street Twin, Kenny Brown DD Subframes, More to come...
There Goes the Neighborhood!!!
Thread Starter
Registered User
Joined: Sep 2001
Posts: 903
From: boxboro, MA, USA
<<<<<160 stat and programming............godwilling my plugs and wires will be with my car tomorrow and installed friday or saturday. i elected to get MSD OTVC wires, made for you wire looms, and am gonna be using the stock ac delco platinum plugs. ill report back later. cross your fingers boys, if this doesnt fix it its opti time, except this time i KNOW the opti going in was working, it came off a silver LT1 96 Z M6 JUST like mine and has a MEAGER 5k miles on it when it came off. it was working 100% and best of all im getting it free cuz he went to the LS1 ignition setup.
brian
brian