What's up AZ fam?! I recently purchased and installed the 3.7L TB and IM package that HeelToe had for sale and I seem to be having some issues. I definitely noticed the gain in ponies and loving it but I'm having some issues with the TB it seems. I've taken the car to have the ECM reset and did the idle relearn process before anything. When I start the car the idle jumps to 1500-1800 then drops down to 800ish and it manages to stay there while the car is sitting there. When I'm out on the road and lets say I'm driving pretty quick and all of a sudden have to come to a quick stop, as the tranny is downshifting on it's own when I come to a complete stop the car bucks or jerks sometimes like if the transmission locked up or something. Also when cruising sometimes I let go of the pedal and the throttle doesn't change. It's as if I'm in cruise control and have to press the brake pedal to slow down. Its a little scary I have to admit. I've seen members with M/T have issues but not many Auto's listed. Any idea what can be my issue?

 

bear with me; as I dont have the 3.7IM package installed, however, ran into this problem or something like it, when i installed Hondata flashpro + 08 Type-S ECU.

my symptoms; on first start up, idle'd VERY high, 1500-1800RPM. I thought, well..I messed with the ECU, maybe I just need to do the Idle relearn process. I did the idle relearn trick that involves holding pedal at 3000RPM for minutes until the Radiator fan comes on. i then let the idle sit for 5 minutes, like all the youtube instructions told me.

while this kind of fixed the high idle issue, at idle.....i kept having a spike when clutching in to neutral at a stop light. the RPM's would go down to 700, like normal....but then SPIKE to about 1000-1300 RPM. if the car was in gear, no doubt it would feel like yours. no doubt the extra RPMs would make the car buck or keep accelerating.

I kept complaining to Dom and he would suggest things to fix it, however, his suggestions and tuning didn't make a difference when coming to a stop.

To me; it kept feeling like a vacuum leak. and it turned out to be a vacuum leak.
on the stock intake manifold; there are lines that control the motor mounts. I hadnt had OEM type motor mounts in a while, so I had ripped those lines off the IM. I went to autozone and picked up a pack of different sized vacuum plugs and plugged up the little control box thingy.

my car now idles at 700RPM and I do not get the REV spike coming to a stop any longer.

 

I'm not sure if the symptoms I've had are the same based on your guys' description, but with both my '06 TL and '12 TL, when I installed the 3.7 IM and TB, I noticed a type of "lurch" when taking my foot off the pedal. Kind of like the TB went from partial open to closed causing engine braking all of a sudden. It doesn't do it all the time. Probably 50%. No symptoms other than that though. I find it weird that it does it with both generations. But no abnormalities in idle.

 

can your bluetooth module see voltage spikes?
it would be interesting to see if the throttle position sensor spikes at those times.

 

here we can see my spike.
I have circled it in red.
throttle pedal is at 0%!! this means it shouldnt be revving to 1300RPM, as the throttle body is closed.
you can see that it's holding at 1000-1300 for a good 2-3 seconds! at a stop light, it sounds like i'm revving at you! I was so embarrassed. lol

 

in conclusion; I think you have a vacuum leak somewhere.

 

Vacuum leak. I had the same issue when I installed my 3.7 mods back in 2015. Dom got rid of the high idle and what not with Hondata but letting the throttle go and the rpms remaining about the same was a result of vacuum leak. Funny enough I got the CEL for it weeks later. But its all fixed, check all hoses and re-tighten the entire manifold setup/intake setup. Make sure all gaskets sit where there are supposed too, etc.

 

So here's an update to my issue and it in fact was a vacuum leak. I pulled the manifold off and checked the thermal gasket and found that it was melting causing it not to seat properly and cause the issues I was having. Swapped it out with another gasket and the car is back to running normal with a little added ponies of course and an annoying whistle from the CAI but I can live with it. Now to have Dom finish up the tuning and be done with it. Thanks for pointing me in the right direction gents!

Here's a pic of the gasket.

 

Is that a special gasket that comes with the kit? It's definitely not the OEM gasket. How much longer till the new gasket also melts?

 

That's a thermal gasket from P2R that helps dissipate heat soak in the IM. That was actually the old one I had on along with my IM spacer. I thought I was able to use it still but it turned out to be the culprit along with my top plate gasket. I found out later that it had oil residue each time I removed the plate and it shouldn't have had any oil seeping out at all.