2008 Viper Throttle body to be installed today on my jeep. will keep updated
08-01-2011, 08:12 PM
#61
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Just installed a Viper TB and the engine light came on immediately. I'll try and clear it with my tuner.
Initial results were a slight gain in power and throttle response. We'll see how it reacts to my Diablo Sport.
FYI, I'm running an Airaid CAI.
I'll post as things come.
Initial results were a slight gain in power and throttle response. We'll see how it reacts to my Diablo Sport.
FYI, I'm running an Airaid CAI.
I'll post as things come.
08-03-2011, 12:52 PM
#62
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FWIW, I wouldn't recommend this mod to anyone who is still trying to decide. I wouldn't call myself a Jeep expert, but I do know a thing or two about engines, as I am a mechanical engineer specializing in engine research.
The V6 in 07-11 jeeps does not have a MAF (mass air flow) sensor, so it runs off of a Speed-Density system using MAP (manifold pressure) and engine RPM. It uses this to know how much fuel and spark to run correctly at different loads. This system also USUALLY uses throttle position to predict for tip in throttle response changes as well as for cross checking the estimated air flow against the MAP sensor. Changing this throttle diameter will change the airflow vs throttle position greatly and thus cause the engine ECU to not be estimating the correct portion of the calibration to run off of. This is not a good thing. It's possible the O2 sensors may be able to see and adjust for this by adding long term fuel trim to band-aid-adjust the calibration to be more correct, but it is not the correct solution. You also may get lucky by the larger throttle leaning out the mixture and running ok without being dangerous, but you also may get the opposite.
The CELs are most likely from the throttle position sensor and MAP sensors telling the ECU that different amounts of air are being predicted. They could also be from the engine needing too much fuel trim from the O2 sensors.
As far as gas mileage increases, it could be possible to get lucky because in theory you are increasing the volumetric efficiency by removing intake restriction. But without a correction to the ECU calibration I would highly suggest against this actually working, other than you getting lucky. I would also suggest to those reporting gains, to not go off what the little mpg readout is telling you and calculate mpg by hand. I bet you get different results to report back to us.
This would all be a different story if the engine had a MAF sensor that it primarily used to run, then the increase in VE could be a real gain.
The V6 in 07-11 jeeps does not have a MAF (mass air flow) sensor, so it runs off of a Speed-Density system using MAP (manifold pressure) and engine RPM. It uses this to know how much fuel and spark to run correctly at different loads. This system also USUALLY uses throttle position to predict for tip in throttle response changes as well as for cross checking the estimated air flow against the MAP sensor. Changing this throttle diameter will change the airflow vs throttle position greatly and thus cause the engine ECU to not be estimating the correct portion of the calibration to run off of. This is not a good thing. It's possible the O2 sensors may be able to see and adjust for this by adding long term fuel trim to band-aid-adjust the calibration to be more correct, but it is not the correct solution. You also may get lucky by the larger throttle leaning out the mixture and running ok without being dangerous, but you also may get the opposite.
The CELs are most likely from the throttle position sensor and MAP sensors telling the ECU that different amounts of air are being predicted. They could also be from the engine needing too much fuel trim from the O2 sensors.
As far as gas mileage increases, it could be possible to get lucky because in theory you are increasing the volumetric efficiency by removing intake restriction. But without a correction to the ECU calibration I would highly suggest against this actually working, other than you getting lucky. I would also suggest to those reporting gains, to not go off what the little mpg readout is telling you and calculate mpg by hand. I bet you get different results to report back to us.
This would all be a different story if the engine had a MAF sensor that it primarily used to run, then the increase in VE could be a real gain.
08-03-2011, 01:19 PM
#63
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As my Jeep isn't a DD, I figured I'd try and experiment a bit... The plan is to take it to a dyno shop and see if they can write a tune to clean up the air/fuel ratio, WOT settings, etc... watch and shoot.
08-06-2011, 01:34 PM
#67
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Anybody have experience with this?
ht tp://www.thefastman.com/ThrottlebodiesDBW3738.asp
ht tp://www.thefastman.com/ThrottlebodiesDBW3738.asp
Last edited by Absolute; 08-06-2011 at 01:40 PM. Reason: please do not include clickable links
I have never had a problem with them at all. 10 mins. to install one
11-02-2011, 11:17 AM
#69
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im over 13,500 miles and have had this on for 6 months and 10,000 miles. still not having any issues(minus the ones i caused offroading, breaking of parts ect haha) 
11-02-2011, 12:39 PM
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Originally Posted by Combsn6
im over 13,500 miles and have had this on for 6 months and 10,000 miles. still not having any issues(minus the ones i caused offroading, breaking of parts ect haha)