Backfiring When hot..OptiSpark?
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 19
Likes: 0
From: Bayonne NJ
Backfiring When hot..OptiSpark?
Recently my 92 with 26K original miles starting running rough. First time its been out in the rain in a very long time.
At idle the car begins to run rough. As she heats up engine runs rougher and rougher. When you try to jump on the gas she begins to backfire consistently with severe acceleration retardation.
I think the root cause could be Opti Spark as it has started to arc.
Do you think this is the true root cause? Anybody know where to get a quality replacement part as the dealer does not stock it.
Also wondering if this is something I should let the dealer handle and do the work as well.
Thanks for your help ....
Joe
At idle the car begins to run rough. As she heats up engine runs rougher and rougher. When you try to jump on the gas she begins to backfire consistently with severe acceleration retardation.
I think the root cause could be Opti Spark as it has started to arc.
Do you think this is the true root cause? Anybody know where to get a quality replacement part as the dealer does not stock it.
Also wondering if this is something I should let the dealer handle and do the work as well.
Thanks for your help ....
Joe
Pro
Joined: Oct 2007
Posts: 739
Likes: 52
From: Reno NV
Sounds like opti is going south. With 26k miles I'm sure you got original plugs, wires and opti. 92 has the worst opti.
My car was doing the same thing. You can do it yourself, if you wanna save $1,000 dollars.
My car was doing the same thing. You can do it yourself, if you wanna save $1,000 dollars.
Race Director
Joined: Jan 2002
Posts: 12,263
Likes: 86
From: O'Fallon Missouri
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Smell your exhaust, when mine was running real rich it would backfire. Turned out I had 2 bad o2's. The opti's are better than most people give them credit, mine has almost 40k since I had to change mine and that was because my water pump decided to take a leak on the opti.
Pro
Joined: Jun 2007
Posts: 747
Likes: 93
From: Marietta, GA
Recently my 92 with 26K original miles starting running rough. First time its been out in the rain in a very long time.
At idle the car begins to run rough. As she heats up engine runs rougher and rougher. When you try to jump on the gas she begins to backfire consistently with severe acceleration retardation.
I think the root cause could be Opti Spark as it has started to arc.
Do you think this is the true root cause? Anybody know where to get a quality replacement part as the dealer does not stock it.
Also wondering if this is something I should let the dealer handle and do the work as well.
Thanks for your help ....
Joe
At idle the car begins to run rough. As she heats up engine runs rougher and rougher. When you try to jump on the gas she begins to backfire consistently with severe acceleration retardation.
I think the root cause could be Opti Spark as it has started to arc.
Do you think this is the true root cause? Anybody know where to get a quality replacement part as the dealer does not stock it.
Also wondering if this is something I should let the dealer handle and do the work as well.
Thanks for your help ....
Joe
Instructor
Joined: Dec 2007
Posts: 156
Likes: 0
From: Powhatan Virginia
Guess it goes without saying consider replacing the water pump also --since you'll have it off anyway(a coolant leak here can cause opti failure---I'd go with MSD since the OEM replacement won't be vented---if you have a reasonable amount of mechanical skill and PATIENCE you can do it yourself---there are many threads on this forum about opti failures/repairs/replacements----good luck
Instructor
Joined: Jun 2007
Posts: 210
Likes: 0
From: Spring Texas
Just did my Opti last Saturday. It was tough but is really not that bad. It is only about 12 bolts to remove along with hoses and other connections. It is really a straight forward operation. However it did not fix my problem. I also had a high RPM backfire as well as no spark above 5000rpm. Same problem is still there. I noticed some arcing on my coil so I am going new coil and wires today. I hope it fixes it. I will let you know. With the new opti it starts better and feels stronger but falls on its face at 5 grand.
Thread Starter
Heel & Toe
Joined: Apr 2008
Posts: 19
Likes: 0
From: Bayonne NJ
Hi Guys,
I finally replaced the OptiSpark. A big difference in performance and acceleration. I noticed it right away.
The water pump appeared to be leaking a bit: I replaced that as well since it had to come out anyway. I wonder if the leaking pump could have caused the Opti to sour
? While I was at it put on new wires too.
Car runs as smooth as a top. If I have a problem with it again I may replace it with one of those aftermarket direct fire ignitions that fire outside of the Opti. Anybody running a mod configuration without the Opti spark?
Thanks for all of your help and suggestions.
Joe
I finally replaced the OptiSpark. A big difference in performance and acceleration. I noticed it right away.
The water pump appeared to be leaking a bit: I replaced that as well since it had to come out anyway. I wonder if the leaking pump could have caused the Opti to sour
? While I was at it put on new wires too.Car runs as smooth as a top. If I have a problem with it again I may replace it with one of those aftermarket direct fire ignitions that fire outside of the Opti. Anybody running a mod configuration without the Opti spark?
Thanks for all of your help and suggestions.
Joe
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