LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Missfire in 96 TA

Thread Tools
 
Search this Thread
 
Old 03-16-2011, 06:35 AM
  #1  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Default Missfire in 96 TA

This is the deal, My water pump went so I pulled it and in the process broke the gear shaft off the timing chain cover. Well at the time not knowing what I was getting in to I made the decision to put it in the shop to have it put back together.(mistake as it turns out). Well when I got it back It ran fine till it warmed up and then the missfire and eventual stall out started. Well Since then I have replaced- CPS twice, opti, cap, rotor, wires, plugs, egr(now deleted), intake elbow and added cold air, tried 2 different MAF sensors. I had the ICM tested and spaced the coil away from the block. I also pulled the intake mani off to have it cleaned and I painted it. deleted the A/C as well. I know some off these things may nt make a diference but just wanted to be clear about everything. After I put it back together this time it seemed to be fine for a while then it all started again. since I pulled this off my other forum account I updated it. here changed plug wires that were burnt badly no change, after the scan results below I put another MAF on it nothing changed, did a visual check of of all grounds nothing to see will be doing physical chaeck if the weather lets up.

Last edited by 9transam6; 03-16-2011 at 06:41 AM.
Old 03-16-2011, 06:37 AM
  #2  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Default

After we scanned it with a dealer scanner. heres a little run down of what we seen that was way out of wack readings wise...


maf reading key on/engine off 10gms ( should b 0gms i belive )

maf reading while cranking 20gms

maf reading while the engine tries to run 21-25gms ( should be 2.5-9 while idling )

injectors while cranking 32ms

injectors while running 35.2ms ( should b 3.5-5.5 )

of course the LT's and ST's where way out of wack and the O2's where stuck rich.

coolant was around 50f when we started and rose to 102f for the little time it ran, so that appears to be working. the map appeared to be reading correct.
Old 03-16-2011, 06:50 AM
  #3  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

did you swap a MAF while you had the scanner? And sometimes the MAF will say somekinda number while key is on, but 20 while cranking seems to be a bit high. Can you data log your car by chance? this way we can see real time data of whats going on. Im assuming no codes are stored or active?
Old 03-16-2011, 10:03 AM
  #4  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Default

yeah thats where the info came from. the second post was copied from my thread on ltx. It was originally posted by my friend that had the scanner. He listed the things he encountered while data logging.
Old 03-16-2011, 10:14 AM
  #5  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

upload a log while having this issue so i can open it up.
Old 03-16-2011, 10:17 AM
  #6  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Default

I personaly wouldnt know ho wto do that at all It was my buddies scanner I think he borrowed it from his work.
Old 03-16-2011, 10:27 AM
  #7  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

ok well tell him he can buy an ALDL to USB cable for cheap and download TTS Datamaster for free and log the car off a lap top anywhere. great program to have and really aids in diag
Old 03-16-2011, 10:41 AM
  #8  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Default

where could I get the cable from???????????
Old 03-16-2011, 10:58 AM
  #9  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

http://www.akmcables.com/ic.htm

this is just one of many places and you can find them for around 60-100 bucks. i bought one from akm cause there good quality
Old 03-16-2011, 11:14 AM
  #10  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Thumbs up

sweet thanks
Old 03-20-2011, 09:51 AM
  #11  
Staging Lane
Thread Starter
 
9transam6's Avatar
 
Join Date: Jan 2011
Location: Hampton,Va
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Default

It was the opti I had replaced it recently so I put it out of my mind. But when nothing else worked I thought maybe when I blew the radiator hose it crapped the opti out again. Well I was right and the cap had a burnt spot in it where it was arcing big time.

Thanks guys for all the help!!
Old 03-20-2011, 10:03 AM
  #12  
TECH Fanatic
iTrader: (8)
 
96TransAmboosted's Avatar
 
Join Date: Jan 2011
Location: Pinellas Park Florida
Posts: 1,550
Likes: 0
Received 0 Likes on 0 Posts
Default

That sucks, but at least you got it fixed. Did they warranty the unit for you or did you have to buy a new one?
Old 03-20-2011, 08:02 PM
  #13  
11 Second Club
iTrader: (10)
 
grn95t/a's Avatar
 
Join Date: Nov 2006
Location: york county, va.
Posts: 802
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by 9transam6
It was the opti I had replaced it recently so I put it out of my mind. But when nothing else worked I thought maybe when I blew the radiator hose it crapped the opti out again. Well I was right and the cap had a burnt spot in it where it was arcing big time.

Thanks guys for all the help!!
all i can say is wow........
Old 03-20-2011, 10:12 PM
  #14  
On The Tree
iTrader: (3)
 
biggriff's Avatar
 
Join Date: Jan 2010
Location: Yorktown, Va
Posts: 116
Likes: 0
Received 0 Likes on 0 Posts
Default

not suprised it was the Opti...grn95ta knows his stuff...when we tried his computer the other day and it didnt work???? grn95t/a called it right away...dude its the Opti...he is pretty sharp on the LT1's...good call Mr Close...and even though you said "man i didnt want to hear you say that" bet your glad you took his advice....you'd still be trouble shooting that thing...instead of cruising it...good luck with the build dude...



Quick Reply: Missfire in 96 TA



All times are GMT -5. The time now is 11:05 PM.