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Discussion Starter #2
Im chasing a miss at idle. also under heavy load at low rpms it stumbles. I have the delteq conversion. I replaced all the coils, put tr55 plus in, accell 8.8 wires, even cleaned the injectors, which all seem to work. I did a leak down test on them no pressure loss over 10 min. I have been pulling the injector leads to see if the idle changes and there is always one that doesn't change but it isn't always the same one.whether it be spark or fuel. Could this be the opti going bad? The previous owner said the opti was bad that's why he put the delteq on but i know the delteq needs a good opti to work. On a side note the fans started coming on right after start up and the check engine light comes on

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Discussion Starter #4
I hooked up my laptop with tunerpro rt on it. I get no fault codes it just shows the fans coming on. I'm hoping to get a snap on scanner hooked up to it tomorrow. If i shut the car off then restart it the light is off until the fans kick on.

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The fans kick on because of the check engine light. Let us know what codes are in it when you get a scanner on it.
 

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Doesnt the LTCC and Delteq need the sensor and degree wheel in the very back of the opti to function (low voltage side)? Have you tried ohming out that portion of the opti? Did you try hooking a fuel pressure gauge out the back of the hood as to be visible while drving and see what the pressure is under load and idle in driving conditions?
 

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Discussion Starter #10
I'm guessing to check check the opti i would go to where the delteq plus into it? And what should the ohms be? I haven't hooked up my fuel gauge under load yet. The car is running pretty rich also

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I'm guessing to check check the opti i would go to where the delteq plus into it? And what should the ohms be? I haven't hooked up my fuel gauge under load yet. The car is running pretty rich also

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Yes you would check it where the Delteq plugs into the opti at, behind the water pump in the upper portion on the passenger side. Im not sure what it would ohm off hand but there is a youtube video called something like diagnos opti which checks for anything that plugs into opti. Shoebox has an awesome site and is very knowledgable on LT1s I'ld follow his suggestions.
 

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I too, am chasing a similar problem with my 1994 Trans Am. I am at the end of my rope on this one! I'm no dummy in the garage, as I've been a mechanic on a professional level for the last 16 years. But this problem has really called my bluff! Ok here is what I have, and what I am dealing with:
A 1994 Pontiac Trans Am with a brand new rebuilt LT1. The motor has been bored .030 over, Mahle forged pistons, Callies H-beam rods, stock crank reconditioned. Cam: Comp cams 07-501-8 cam, .488 .495 lift cam. I also replaced the roller lifters with new comp rollers as well. Stock 7.200 long pushrods, and the factory stamped steel rocker arms. The deck has been milled, as well as the heads, can't remember how much was taken off. The whole rotating assembly has been balanced as well. I am running a Lunati timing chain and gear set as well. The intake is stock, as well as the throttle body, injectors, and exhaust manifolds. I replaced the O2 sensors with brand new Bosch sensors, as well as the opti-spark with a reman Cardone distributor from Auto Zone. I run Autolite plug wires with TR-55 spark plugs. The computer has not been tuned as of yet. Now here is thr problem I am chasing:
I have a stumble, and or a miss in this engine that I absolutely cannot figure out. The old engine that was in this car had the same problem as well. It ran when I pulled it. I assumed the factory optispark was bad, or at least on its way out. Naturally I went out and bought a new one for my brand new engine. This did not cure the problem. I thought, ok..I have a faulty distributor. I tore the reman back off the engine and returned it to auto zone for a different one. Nothing changed. I replaced the ICM, and ignition coil with no change as well. The engine is underpowered at low RPM's with a bad stumble and miss, especially when accelerated lightly at cruising speed when the torque converter is locked up. When I give it WOT, it will stumble badly before it downshifts, then 6,500 rpms later it runs fine like it should. I checked for a bad plug, bad plug wire, and I have found nothing. I don't have any check engine lights on either. Now what could cause two engines to do this very same thing? I have over $6,000 invested in this new motor, and I don't want to blow it to the moon because of something stupid thats going wrong with it. PLEASE HELP!
 

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Discussion Starter #17
I threw a tps on yesterday no change. My next thought is that it seems to stumble. After it loads up. I'm thinking about reprogramming it to think it has larger injectors. So it leans itself out.
 

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Discussion Starter #20
Yes i did it seemed fine. For the price it was worth a shot. I'm really shooting in the dark at this point. I just watched the opti diagnostic video Ann I'm going to start going through that.

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