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Dguth 01-14-2013 07:09 PM

Finally installed Catch Can but still seeing Knock
So, I finally got my catch can in this weekend from Billet and had it installed. Vehicle has about 11,000 miles on it, so I'm way overdue to get it. Had to custom make some spacers so it would fit far enough out away from the plastic cover. They should have shipped more spacers with the device.

After putting it in, we did remove the throttle body and put our hand in to see if we could feel oil. It definitely had oil in the intake area. We didn't have time to pull the manifold and clean it. My question is will the oil in there eventually burn off and if so how long will it take?

I have been noticing some problems with heavy knock on the Trinity: up to 12 st knock and pulling to 1-3 LT knock with WOT passes. At first I thought it was bad gas, now I'm thinking it might have been the oil. The knock happens not only on the tunes but also stock parameters as well.

Just wondering but could anything else be causing the knock. On one particularly long trip a couple months ago I had a major engine misfire as the check engine blinking light came on but it stored no code for the dealer to investigate properly. I would wonder if I should replace the plugs - would that be wise?

Please give me your feedback if I should be investigating something else.

A.V.GCSRT8 01-14-2013 08:33 PM

Re: Finally installed Catch Can but still seeing Knock
Not to scare you but there is no way the oil is gonna cause that much knock, Chrysler would not have released it if it did. Either you have terrible gas in your area or something is not right. Maybe it's a combo of bad gas and the oil, 12 st is way to high. You don't need to take off the mani to clean it, just get some sea foam and run it thru the intake manifold thru the brake booster line and it should clean it out really well. There is a how to Johan posted I think on the red site

ACEofSRT 01-15-2013 09:59 AM

What tune and gas are you running?

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Scottina06 01-15-2013 12:14 PM

Re: Finally installed Catch Can but still seeing Knock
gotta be the winter gas mix

Dguth 01-15-2013 02:45 PM

Re: Finally installed Catch Can but still seeing Knock
I have the Diablo Trinity with the 93 tune. I usually only run 93 octane gas from BP but got some different gas from a Bullova station last week. I have reverted back to my usual BP gas. I also usually try to add in some Lucas Octane booster as well.

As I stated above the knock is happening in the tune as well as stock. I think the PCM is reacting to the LT knock over time. For example when I reset the battery and did a few pass runs, I quickly noticed the max timing on my base spark was up to 48 but then I also saw the ST and LT go as high as 12 and 3.5. Previous to this the PCM was only showing max spark of 46.00 and the highest st kr I would see was around 4. I believe the PCM reacts to LT Knock and automatically starts to reduce timing in the tune permanently. So it almost feels like a false sense of improvement in knock.

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