JHM Tune - Readiness only shows 1 fail, but does not pass emmissions

Normally I have been able to reset my cel from a lean condition (most likely from an air leak in the IM when I re-installed it after a carbon clean) set the readiness indicators by driving around and pass emissions. This year I had 2 that would never set, one of the banks post cat readings and the SAI.

SAI’s are about $700 and do not exist (or they say a three month lead time - which I have found to equate to NLA). I tried a couple used units, both arrived dead, even though they said they were tested.

As a last resort I decided to get the JHM tune (including the SAI delete). While I still get my lean CEL, VCDS says the readiness indicators were all set except the SAI (oddly enough since I expected that one to be set due to the SAI delete).

Off to the inspection, and it fails again due to readiness.

So, I am about to do 2 things:

  1. Uninstall the tune and see if I can get all except the SAI to set and get it re-inspected

  2. With great resistance, put an order in for an overpriced SAI, since I do not plan to drop the engine and replace the cats any time soon

Does anyone else have any advice or maybe an explanation why the JHM tune would screw with the readiness faking me out that they are set when they are not.



I had the issue with the tune when I got the SAI delete it would never pass inspection unless I tuned it back to stock. So I told Jhm remove the SAI delete and ever since after that it’s been passing

Well now my SAI pump just said incorrect air flow and its running lean so I’m guessing the pump is on its death bed lol

So it passed with the tune but without the SAI delete?


Emissions stuff is tough. Generally speaking any company that tunes is probably going to tell you they can’t or won’t be able to get the car to pass readiness as that would technically be against the law and with the EPA and other government bodies raiding shops these past few years even companies like APR have dumped their stage 2 catless tunes.

Something like the JHM SAI off tune isn’t really meant for you to pass emissions as it is for you to be able to drive the car and not have a CEL or have the SAI system run and then cause the car to cold start like crap. Also SAI off is really different per person. Some people just take out the combi valves and block off the plate. Some take out the entire system fully so it’s kinda a hard target for one company to hit without just coding out and then programming off all of the features. This is over all most desirable for everyone but isn’t always the best for emissions dodging

Take into consideration you have so many different states with so many different emissions passing requirements. The tune works for most to help bridge the gap and many will pass but in the end it’s kinda weather or not the requirements fall within what JHM is doing to try and help. And it’s a fine line… Overall I think most are just shooting to not have the CEL on and not have all the negative issues that come with the SAI functional.

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Yeah, like the fact SAI’s don’t exist for the V10 and if they did would cost $700 for the unicorn pump.

I’m going to see if there is a cross reference with Pierburg for a part that would work. My guess is the volume of air they have to move for the V10 is the difference.

In the meantime I just need the stickers from PA so I don’t get a $150 ticket.


It passed without the SAI delete like literally after 10 mins of driving for me

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Like for last 2 years I had to keep putting it back to stock just to inspect it but now I just removed the SAI delete on the tune and it passes without me going back to stock. By the way I’m from NY

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