Opti Spark Problem?
Thread Starter
Instructor
Joined: Mar 2015
Posts: 189
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From: Los Alamos NM
Opti Spark Problem?
96 CE LT-1, 120K miles
I'm having problems with the car running rough at idle and sometimes difficult to start without giving it some gas. I'm used to cars that require the foot on the brake to start so needing to give it gas seems odd to me. I've replaced the fuel injectors and it got a little better, plus more power, plugs and wires, fuel filter and cleaned out the air filter (K&N).
I don't know that much about working on engines, but I'm beginning to learn. Would those symptoms match a problem with the Optispark? I believe it is the original 20 year old equipment. Since there are so many horror stories on replacing the Opti and finding a good one seems to be difficult, I want to be sure before I start the hunt to find a good one.
I'm having problems with the car running rough at idle and sometimes difficult to start without giving it some gas. I'm used to cars that require the foot on the brake to start so needing to give it gas seems odd to me. I've replaced the fuel injectors and it got a little better, plus more power, plugs and wires, fuel filter and cleaned out the air filter (K&N).
I don't know that much about working on engines, but I'm beginning to learn. Would those symptoms match a problem with the Optispark? I believe it is the original 20 year old equipment. Since there are so many horror stories on replacing the Opti and finding a good one seems to be difficult, I want to be sure before I start the hunt to find a good one.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,072
From: Lansing MI
96 CE LT-1, 120K miles
I'm having problems with the car running rough at idle and sometimes difficult to start without giving it some gas. I'm used to cars that require the foot on the brake to start so needing to give it gas seems odd to me. I've replaced the fuel injectors and it got a little better, plus more power, plugs and wires, fuel filter and cleaned out the air filter (K&N).
I don't know that much about working on engines, but I'm beginning to learn. Would those symptoms match a problem with the Optispark? I believe it is the original 20 year old equipment. Since there are so many horror stories on replacing the Opti and finding a good one seems to be difficult, I want to be sure before I start the hunt to find a good one.
I'm having problems with the car running rough at idle and sometimes difficult to start without giving it some gas. I'm used to cars that require the foot on the brake to start so needing to give it gas seems odd to me. I've replaced the fuel injectors and it got a little better, plus more power, plugs and wires, fuel filter and cleaned out the air filter (K&N).
I don't know that much about working on engines, but I'm beginning to learn. Would those symptoms match a problem with the Optispark? I believe it is the original 20 year old equipment. Since there are so many horror stories on replacing the Opti and finding a good one seems to be difficult, I want to be sure before I start the hunt to find a good one.
Last edited by PatternDayTrader; May 27, 2016 at 06:37 PM.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,072
From: Lansing MI
There is a test port on the fuel rail. Here is a link to a picture. It is labeled "Schrader valve".
https://www.bing.com/images/search?q...7o0&ajaxhist=0
Thread Starter
Instructor
Joined: Mar 2015
Posts: 189
Likes: 0
From: Los Alamos NM
OK, so the fuel pressure is only 39 (according to FSM it should be between 41 and 47. The pressure stays consistent after the fuel pump is turned off, so I'm guessing it might be the regulator. Interesting since I replaced that just last year shortly after replacing the entire fuel sending unit and the fuel pump. I did also just realize that I bought the fuel filter, but apparently I didn't get it installed yet as it's sitting on my passenger seat still in the package.
Wait a minute, I did the pressure test with the gas cap off. Should it have been on and if so shouldn't it raise the pressure slightly?
Wait a minute, I did the pressure test with the gas cap off. Should it have been on and if so shouldn't it raise the pressure slightly?
Last edited by toricred; May 28, 2016 at 04:52 PM.
Race Director
Joined: Oct 2008
Posts: 17,982
Likes: 1,072
From: Lansing MI
OK, so the fuel pressure is only 39 (according to FSM it should be between 41 and 47. The pressure stays consistent after the fuel pump is turned off, so I'm guessing it might be the regulator. Interesting since I replaced that just last year shortly after replacing the entire fuel sending unit and the fuel pump. I did also just realize that I bought the fuel filter, but apparently I didn't get it installed yet as it's sitting on my passenger seat still in the package.
Last edited by PatternDayTrader; May 28, 2016 at 04:58 PM.
Thread Starter
Instructor
Joined: Mar 2015
Posts: 189
Likes: 0
From: Los Alamos NM
What's the easiest way to test for a stuck egr valve. I'll look at the MAF sensor screen later today, but I need to know if I'll need any more parts or tools before AutoZone closes.
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Thread Starter
Instructor
Joined: Mar 2015
Posts: 189
Likes: 0
From: Los Alamos NM
I put in the new EGR valve today. It was a pain to get the old one out and the new one in because of the tight space back there, but it seems to have fixed the starting and idling problems. It's too soon to tell on the gas mileage.