LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Installed new opti now car just backfires!

Thread Tools
 
Search this Thread
 
Old Oct 28, 2010 | 08:43 PM
  #1  
dirtgar's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 117
From: Cheyenne, WY
Installed new opti now car just backfires!

Just installed a new opti, now the car just back fires really bad, any ideas of what could be wrong?

I think I pluged all the plug wires to the correct opti plug, but I think I should double check. Do you guys think that incorrect firing order can cause the car just to back fire while cranking??
Old Oct 28, 2010 | 09:07 PM
  #2  
RamAir95TA's Avatar
Registered User
 
Joined: Sep 2001
Posts: 4,152
From: Woodstown, NJ
Backfiring is almost 100% of the time due to crossed plug wires.
Old Oct 28, 2010 | 09:48 PM
  #3  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,110
From: Hell was full so they sent me to NJ
You have to add a "Signature", with basic info about your car - year, model, engine, trans and major mods. That's the only way people can help you accurately.

Are you sure you indexed the Opti correctly to the cam? That would either be a problem with the splined drive shaft (93-94 unvented) being misaligned, or the cam dowel pin in the wrong hole (95-97). If we knew what year it was, we might be able to get more specific.
Old Oct 28, 2010 | 09:57 PM
  #4  
dirtgar's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 117
From: Cheyenne, WY
Got it Im gonna fill out the signature section!
Old Oct 28, 2010 | 09:58 PM
  #5  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,110
From: Hell was full so they sent me to NJ
If you don't, you're just hurting your chances of getting help.
Old Oct 28, 2010 | 10:03 PM
  #6  
dirtgar's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 117
From: Cheyenne, WY
Hey Injueer I have a 97, Im trying to remember if it had a dowel. I dont think it did all I remember was that it had a piece that stuck out and I tried to line up and then I slighly pushed the opti in.
Old Oct 28, 2010 | 10:07 PM
  #7  
Injuneer's Avatar
Administrator
 
Joined: Nov 1998
Posts: 71,110
From: Hell was full so they sent me to NJ
The "piece that stuck out" would be the cam dowel pin.

From Shoebox:

http://shbox.com/1/opti_back.jpg

If you "pushed" the Opti in with any force, there's a good chance you had it in the wrong hole.

Also:

http://www.enginebuildermag.com/Cont...0000003987.gif
Old Oct 29, 2010 | 05:42 AM
  #8  
Guest47904's Avatar
Guest
 
Joined: Sep 2004
Posts: 0
All y'all keep forgetting this guy.

https://www.camaroz28.com/forums/sho...d.php?t=777043

https://www.camaroz28.com/forums/sho...d.php?t=778662

Or should I say, same old problem but now the 3rd post for an ignition problem. Who can follow this?

Oh yeah one other thing I just noticed on is Garage. He's the 6th owner of this car since 97.

Last edited by Guest47904; Oct 29, 2010 at 05:46 AM.
Old Oct 29, 2010 | 08:13 AM
  #9  
dirtgar's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 117
From: Cheyenne, WY
Speedy what do you mean every one is forgetting this guy??
My fuse was burning and you helped me find the wire that was broken and know that eveything is put back together to include the new opti the z28 just backfires really bad when I crank the ignition. Hey I'm just trying to get some help, from a bunch of guys who obviously have more experinace working on cars than I do. What do you mean Im the 6th owner, what does that have to do with anything?? I got the car for a low price and that was what I could afford, I had the money then I would have bought newer z28 with less owners and with a lot less miles.
Old Oct 29, 2010 | 04:21 PM
  #10  
IceMatrix69's Avatar
Registered User
 
Joined: Jan 2010
Posts: 74
From: Fostoria, Ohio
When Speedy makes comment towards you being the 6th owner he's bringing knowledge to the car itself. Generally speaking, when a 13 yr. old vehicle has had that many owners there is a reason for it, usually mechanical issues.

You may have bought yourself someone else's problem, just sayin
Old Oct 29, 2010 | 04:35 PM
  #11  
dirtgar's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 117
From: Cheyenne, WY
Yeah I proabably did, I just hope I can survive this Camaro. It's my first American V-8 car an boy do I love the speed! but if it's always going to be broken down then I dont know If I can handle that??? Maybe I should have saved up more and bought a newer z28 somehitng like a 2001 or 2002 LS1
Old Oct 29, 2010 | 04:41 PM
  #12  
Chaos1187's Avatar
Registered User
 
Joined: Jun 2010
Posts: 275
If you dont have money holmes, by a ALDL Cable and the software aaaaand a fuel pump guage. In the LONG run it will save you a LOT of money!

And dont worry about Speedy hes a smart guy and doesnt mean to be some jumpy lol
Old Oct 29, 2010 | 05:23 PM
  #13  
rskrause's Avatar
Moderator
 
Joined: Dec 1969
Posts: 10,745
From: Buffalo, New York
Is it an OEM opti? Did you recheck the plug wires? Are you sure it is indexed right? Did it run right before or are you trying to solve a prexisting problem?

Rich
Old Oct 29, 2010 | 11:51 PM
  #14  
Procharged94Lt1's Avatar
Registered User
 
Joined: Dec 2005
Posts: 907
Originally Posted by Injuneer
If you "pushed" in with any force, there's a good chance you had it in the wrong hole.
Funny, I had an ex-girlfriend that claimed the same thing....

The opti does a good job when installed correctly.

The backfiring def sounds like either some crossed wires or incorrectly indexed like was stated.

To make your life easier label your wires with either a sharpie marker on the opti end or buy some wire labels. They are cheap and make life simple. I also wrote right on the distributer with said sharpie and labeled it to make sure the wires aren't crossed. I spent hours the one time trying to figure out why my car ran like crap only to find crossed wires- felt like a complete moron that it was something so simple...
Old Oct 30, 2010 | 07:37 AM
  #15  
dirtgar's Avatar
Thread Starter
Registered User
 
Joined: Sep 2010
Posts: 117
From: Cheyenne, WY
Thanks guys for the tips! Right now Im in the middle of trying to check the wires, I noticed that I had two wires crossed but I think I have more so I will keep working on it till Im sure they are pluged in correctly.



All times are GMT -5. The time now is 01:48 AM.