'97 LT1 misfiring troubles
#1
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Oct 2005
Location: Holland Twp/Milford, New Jersey
Posts: 1,419
Likes: 0
Received 1 Like
on
1 Post
'97 LT1 misfiring troubles
I have a 1997 TA Ram Air with 63,xxx mi. Just the other day, I was cruising down the highway to shcool, and my Check Engine light came on, but went off again shortly after. Then, after classes were out, it went on again down the highway and stayed on. So, I got it checked out and it said there were a few misfires. So, I thought nothing of it, and had the light turned off. A couple hundred miles later, the light came back on when I revved it for one of my friends. Could it be this misfire again? My father, who is a technician, says it'll miss when I rev it (obviously). But after revving it just ONCE?? This can;t be normal, can it? What is causing this? I hope it's just a bad plug somewhere. Is it possible that the optispark is letting go? I can't afford to be replacing my entire ignition system... Has this ever happened to anyone else? What do you guys suppose I should do about this? Any help would be greatly appreciated guys. Thanks!
#2
TECH Regular
iTrader: (1)
Join Date: Feb 2005
Location: Bethlehem, PA
Posts: 416
Likes: 0
Received 0 Likes
on
0 Posts
Nice hood, man....
Random misfires can be real tough. Get your computer scanned (free at autozone or Advance). See what that tells you and let us know. You are fortunate that your check engine light comes on when it misses.
Random misfires can be real tough. Get your computer scanned (free at autozone or Advance). See what that tells you and let us know. You are fortunate that your check engine light comes on when it misses.
#3
as stated, scan it, see what you're looking at. It may tell you what cylnder is misfiring, or it may just say random misfire. I see plugs and wires in your future. (well really just wires, but while your in there)
Put that car in a dark garage and look for arching while you rev the engine, check along the back of the manifolds as this is where alot of the wires go bad from routing.
My last guess would be your optispark.
Put that car in a dark garage and look for arching while you rev the engine, check along the back of the manifolds as this is where alot of the wires go bad from routing.
My last guess would be your optispark.
#4
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Oct 2005
Location: Holland Twp/Milford, New Jersey
Posts: 1,419
Likes: 0
Received 1 Like
on
1 Post
hmm.. i just found out i may have a slight water pump leak, and that'll cause the optispark to go bad... so, i guess i'll just have to rip apart the whole front of the motor lol.
#5
TECH Regular
iTrader: (1)
Join Date: Feb 2005
Location: Bethlehem, PA
Posts: 416
Likes: 0
Received 0 Likes
on
0 Posts
Hang on there dude!!
Just because your water pump is leaking, doesn't mean your opti is shot. If you had a 94... maybe. But there were improvements made in 95 to prevent moisture from getting in there. Most of the time, if your opti is bad, it will leave you stranded on the road. If you're willing to spend the extra couple hundred bucks, I guess I'd put a new one in if your going to replace the water pump. The opti has gotten a bad rap over the years but mostly because its so hard to get to. Its actually a pretty reliable distributor. I've been there and done that with mine. I went through all the trouble to replace my opti and that wasn't it. I was not happy after all that work. My miss was being caused by a bad injector. So, like I said before, check your codes. No use wasting all that time for nothing.
A little story about a dealership. I just replaced the opti and still had the miss. Went the dealer for help. They told me that they wanted to replace the opti. I said.. did you look at it? its brand new!. They said that they wanted to do it anyway to make sure it was done right.... I guess I must have had "SUCKER" stamped on my forehead. I kindly asked for my keys and never went back to a dealer since. And neither have any of my friends (at least to that dealership).
Just because your water pump is leaking, doesn't mean your opti is shot. If you had a 94... maybe. But there were improvements made in 95 to prevent moisture from getting in there. Most of the time, if your opti is bad, it will leave you stranded on the road. If you're willing to spend the extra couple hundred bucks, I guess I'd put a new one in if your going to replace the water pump. The opti has gotten a bad rap over the years but mostly because its so hard to get to. Its actually a pretty reliable distributor. I've been there and done that with mine. I went through all the trouble to replace my opti and that wasn't it. I was not happy after all that work. My miss was being caused by a bad injector. So, like I said before, check your codes. No use wasting all that time for nothing.
A little story about a dealership. I just replaced the opti and still had the miss. Went the dealer for help. They told me that they wanted to replace the opti. I said.. did you look at it? its brand new!. They said that they wanted to do it anyway to make sure it was done right.... I guess I must have had "SUCKER" stamped on my forehead. I kindly asked for my keys and never went back to a dealer since. And neither have any of my friends (at least to that dealership).
#6
well, I would do your plugs and wires and see where that leaves you.. you said you "may" have a waterpump leak. You KNOW you have a missfire, so address it. You're leak could be one of about six hoses in the area. While your up close and personal changing the plugs and wires, I'm sure you'll figure out the leak.
Do your plugs and wires first, then the opti/pump if needed. You might as well, you wouldn't change the opti and keep the old wires and plugs would you?
Do your plugs and wires first, then the opti/pump if needed. You might as well, you wouldn't change the opti and keep the old wires and plugs would you?
#7
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Oct 2005
Location: Holland Twp/Milford, New Jersey
Posts: 1,419
Likes: 0
Received 1 Like
on
1 Post
i was planning on changing the entire system, so everything will be brand new (and i won't have to worry about anything). when we coded it, it said EGR (which is no big deal) and a few misfires (which is currently causing my check engine light). also, when we checked under the hood and went under the car and everything and all the leaks were coming directly from the water pump, not the hoses. usually, when the water pump has a leak, the opti is doomed, because its right under it. i guess i'll figure out what the problem is when i pull the car over the pit and tear down the motor for the new exhaust, and for the new water pump.
Trending Topics
#8
i dunno about the opti. I've seen plenty of 97's go way past 120k and never need one, no matter what has been thrown at them. as stated previously, its the earlier models specifically the 94 that had major issues. If you do change out the opti, you want to send me your old one?
#9
11 Second Club
iTrader: (6)
you may be getting a little water in the opti from the leaking waterpump, change the pump and let the opti dry out a little before you go drop a ton on a new opti. My pump blew on my 94 and I was lucky it didn't take out my opti...however i did get a ton of water on the front of the motor after a real bad rain storm here and my car had a slight miss for a few days, I let the car still out in the sun for 2-3 days and it cleared up...
good luck
good luck
#10
TECH Fanatic
Thread Starter
iTrader: (8)
Join Date: Oct 2005
Location: Holland Twp/Milford, New Jersey
Posts: 1,419
Likes: 0
Received 1 Like
on
1 Post
Hmmm. My Father is a Masters Technician and he's been doing some research on the LT1. According to all of his sources, all LT1's (no matter what year) shared the same problem with the water pump/optispark. The optispark has been known to have problems withstanding such pressure at high RPM's, which is where we've diagnosed the misfires. It can most likely be a simple plug or wire, but I'm most likely going to play it safe on this one and replace everything. It will eventually need all of it in the long run, so why not just do it now? I plan on keeping this car until it can no longer make it up my driveway.
#11
TECH Regular
iTrader: (1)
Join Date: Feb 2005
Location: Bethlehem, PA
Posts: 416
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by sdm1234
Hmmm. My Father is a Masters Technician and he's been doing some research on the LT1. According to all of his sources, all LT1's (no matter what year) shared the same problem with the water pump/optispark. The optispark has been known to have problems withstanding such pressure at high RPM's, which is where we've diagnosed the misfires. It can most likely be a simple plug or wire, but I'm most likely going to play it safe on this one and replace everything. It will eventually need all of it in the long run, so why not just do it now? I plan on keeping this car until it can no longer make it up my driveway.
#13
Ok. so i have a 95' firebird formula. WITH the same exact problem. i have completly redone the whole igniton opti, wires, plugs, and coil. OK all good right?? wrong! i still have a miss! but heres the problem its a new motor and for some odd reason a diognostic will not read my computer? before the motor swap it was fine. can anyone help me???
#14
ok so i am having the same problem its a rebuilt 350 in a 95 firebird formula. it has a new igniton system and fuel system. but its still miss fireing. it ran fine till about a month after the new rebuild??? but a diagnotic will not read my computer can anyone give me any advice??? i dont know which way to go from here
#15
Teching In
iTrader: (1)
Join Date: Apr 2008
Location: Terre Haute, Indiana
Posts: 19
Likes: 0
Received 0 Likes
on
0 Posts
ok so i am having the same problem its a rebuilt 350 in a 95 firebird formula. it has a new igniton system and fuel system. but its still miss fireing. it ran fine till about a month after the new rebuild??? but a diagnotic will not read my computer can anyone give me any advice??? i dont know which way to go from here