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· Landscaping Professional
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How closely together are the MAP and Temp leads on the ECU connector? The sensors on the engine are not physically close, but I would suspect maybe you have a splice or a pin connector issue. Engine voltage starts a bit low, but then comes up to a normal range. I wonder if the voltage regulator section is causing some weird daisy chain problems.
 

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It's a Speed/Density system, so the air temperature along with the MAP and TPS readings are crucial to calculating air density. If one of the inputs goes bad, the JTEC uses stored values in the engine map to back-calculate approximate readings for the lost sensor.
 
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· Landscaping Professional
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The damned coil packs are about as hard to get to as one could imagine. You would have an easier time just buying a set of gaskets and pulling the intake manifold. Then again, the fuel line disconnect is a bitch to reach too.
 

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Thanks for the update. I hope you get to the bottom of this. Remember - Plug & Play is far superior to Splice & Pray.
 
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· Landscaping Professional
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Couple of Q's:

Do you still have cats? What does the rest of the exhaust consist of? Maybe you have some restriction that eventually causes it to fail safe?

Has it given you problems with backfiring? Maybe you have a blown turbo seal and it's dumping oil causing the smoke?

Are your O2s below or above the turbos? Have you inspected them?

Any chance you have a bad crank sensor or wire? On later JTECs, they only sync the cam to start the motor, then it runs on crank trigger. Not sure how the AEM works.
 

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I looked at the graphs again a few moments ago on a large screen and am trying to see what I think now. What we need to focus on is the time period from about 28-38 sec for causation. After that, it is about 10 more seconds until your protections, etc start to act extremely weird. What I see now is that at 0:28, your throttle and load factors start to climb for about 2-3 secs, then your injector duty drops out to zero. At this time, your idle air circuit kicks in and your AFRs drop to recover. Then, your RPM wavers noticeably while the wheel speed increases. Next you have a couple more Injector drops and Idle ups, then Idle stays flat and you have more Injector drops with fairly constant speed. I think it's TPS resistor/crank speedand MAP signal related. If your MAP sensor has oil accumulated in it, you may have delayed signal response not in time with input from other sensors.

You've checked your grounds and circuit resistances and discovered/corrected a couple of issues. Oil control is another influencing factor. How do the plugs looks - OK, or oil fouling indicated?
 

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I would call Dan Lesser at VSP. Give him an overview and ask what he would charge hourly for consultation. He's brilliant at that stuff, but shared knowledge isn't always free. He can be blunt and may ask why you did some of the things you did because he knows they aren't core issues.
 
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