OK. This is my brother's car that I did a month ago. I can't find where I posted the report so, I messed that up and I'll post pics here and ask some questions.
We got a extra TB from a junkyard because this was the first groove that I did, and it made sense to take that precaution. I did the groove and he hasn't seen a significant response. Then, after talking to Ron, capped off the PVC connection and even shorted out the battery leads to reset the ECM. After a month without my brother seeing any difference, I grooved his original TB. This time with a business card as a spacer, the large bit and JBquick. Difference-The first Groove was done with the medium bit to avoid the coolant lines going through the TB, and it was done at, what turned out to be, almost 90 degrees to the TB 'plane' and right next to the plate.

SO. now he has the original TB in, with the Groove done about 2~3mm from the plate at closed position (which is that 'almost 90 degrees). The Groove 'drop-off is pretty darn close to 22 degrees of the plane of the TB.
We did a test run and he's not sure about the difference now. Although it should be noted that this is a 1.8L engine 4cyl, 5-speed manual.. not much horse power to begin with.
OK.. now with the questions
You'll see in the pics that there are 2 hoses coming from the valve cover. One(A) goes to the intake plenum (PVC valve hose) and one ( goes to the intake hose before the TB. During the past month, We had the PVC port, at/from the intake plenum, capped off, with the tube just tilted up free, described as 'A'.
The hose 'B' was still connected to the 'Main intake hose' just before the TB. There was a lot of oil residue in that 'Main hose'. 'B' had a slight pulsating pressure coming out of it, basically pushing the oil vapor into the TB. Upon re-connecting the PVC vacuum hose 'A' back to the plenum, hose 'B' now has vacuum.

As it is now... The PVC hose 'A' is reconnected. The hose 'B' is now plugged with a bolt (coming from valve cover) and capped at the 'Main hose' port. On his way home, my brother said now it seems like he has more low end power and less high end. (this was done by text, so I didn't get to inquire more info)
Any suggestions on how to get my brother's car to get what everyone else gets?

my finger is on hose A, hose B is to the outside of my brother's hand has he is putting on the TB
the other pic has my finger's shadow on hose B. These pics were taken before hose A was re-connected so I could use them here.
Thanks in advance,
Heathen (back in Vegas for the next month)

Hi Heathen,
Does this engine have an Idle Air Control?

I have a 1999 Hyundai Accent with a 1.5L 4cyl.

Engine looks like this...



On my TB there is the two heater lines underneath and in front of that the second hose from the 'valve cover'. I moved that to the plenum air intake along with the PCV line.
( I also think I know where my engine oil is going to... I don't think there is a valve involved in that plumbing!)

Back to the Idle Air Control... if there is one, you need to reduce the pathway. It can be on either side but it does need to be reduced.

There may be another line connected to a passive egr.

Once you've got that part figured out you can move on to regapping the spark plugs by 20%...

I regrooved mine, noticed an anomaly that I didn't fix... wanted to see the effect...

Rather interesting, once the engine is warmed up (manual trans) I can just lean on the pedal and the rpm's kick up. When I'm driving and find the 'sweet spot' it really gets up but because of the anomaly it loses the pocket after awhile and drives regular.

It really does let you know that the Groove is doing its thing.

Basically if your not seeing any mpg response it's usually about vacuum.


Karl Fortner
Tacoma, Wa.