Dodge SRT Viper Forums : ViperAlley banner
21 - 31 of 31 Posts

·
Landscaping Professional
Joined
·
14,196 Posts
Thanks for the update. I hope you get to the bottom of this. Remember - Plug & Play is far superior to Splice & Pray.
 
  • Like
Reactions: RobV

·
Registered
Joined
·
655 Posts
Discussion Starter · #22 ·
RSI did all the wiring, for me it was Plug and Play. Well, until now.

I'm about to give up and take it to a tuner shop that deals with Infinities and other aftermarket ECU's. They mostly deal with Corvettes, adding turbo systems and whatever else. I'd think they would be able to find it faster than I can just working on it a couple or three times a week.

I run it for 20-30 minutes and sometimes it quits and I can debug until it cools down, other times it runs fine and I shut it off and try another day.
 

·
Registered
Joined
·
655 Posts
Discussion Starter · #24 ·
Perhaps, the tech wanted me to find a sensor ground that goes bad, but seeing that I can't find it, maybe it's time for them to take a look at the ECU.

Thanks for the suggestion.
 

·
Premium Member
Joined
·
19,392 Posts
I have a spare AEM, you can get the tune transferred over and see it that fixes the issue and isolate the AEM as the problem or not. Shoot me a message if you want to borrow it
 
  • Like
Reactions: CottonMouth

·
Registered
Joined
·
655 Posts
Discussion Starter · #26 ·
Well thank you, that's very nice of you to offer. I'll let you know.
Maybe I should just stop working on it, now for some reason it won't rev past 4-5k rpm. I must have done something when I was trying to find the issue. Now I have two issues :(
 

·
Premium Member
Joined
·
19,392 Posts
Any update?
 

·
Registered
Joined
·
655 Posts
Discussion Starter · #28 ·
I sent the PCM to AEM to have them replace a broken USB connector, and take a look at it in the hope of finding something wrong with it. It turned out to be fine. I haven't been able to look at the stalling issue much since it's started dumping out smoke in the exhaust again due to an issue with the turbo's and the oil scavenging- I've been trying to add an oil-air separator to it so 1) I don't have to drain a catch can and 2) I don't have a mess in the engine compartment. However it's messed up the oil scavenging, hence the clouds of smoke from the exhaust.
I'm sick of dealing with these issues but now that it's winter, it can't be driven much anyway so maybe I'll make some progress. I would take it to a shop (like a performance tuner, not Walmart Auto Care) but typically they don't want to deal with someone else's problems. Ugh, it needs new tires too. Anyone want to buy barely used, 7 year old, super wide Viper tires?
 

·
Landscaping Professional
Joined
·
14,196 Posts
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.
 

·
Landscaping Professional
Joined
·
14,196 Posts
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?
 

·
Registered
Joined
·
655 Posts
Discussion Starter · #31 ·
I had cats, they disintegrated so I removed what was left of them.
The O2 sensors are before the turbos.
No backfires.
I'll check the crank sensor wire- I should be able to plot the signal in the Infinity tuner program. It's always taken more turns of the engine to start than you'd expect (to get 'sync' according to AEM). Pretty annoying. The stock one isn't like that I'd bet.

Once I get the oil/smoking issue resolved I'll drive it more and see if I still have the problem- it might, but probably wasn't, have been fixed by getting the harness off of the heat shield above the left turbo.

I'll check the MAP sensor- it's up pretty high so I don't think there's oil on it but I did get a lot of oil in the plenum awhile back so it's possible. And I'll pull the plugs.

Thanks for the ideas.
 
21 - 31 of 31 Posts
Top