2001 Ford Windstar, 3.8L V6

Everything was easily accessible. The Throttle Body (TB) has 4 bolts; one is hidden by a bracket. Take the spring off and know where it goes, because when the TB comes off its mount, the spring will pop off. The TB was dirty, so I spent most of my time cleaning it.

There was not much room between the plate and edge of the TB, so I used the medium size bit. I built up the back of the groove location with JB Weld Steel, but the medium bit did not go through. It took the groove well – very clean and consistent cut.

PCV valve is right in front next to the oil cap. The vac hose goes into the air intake manifold just after the TB where the groove is. I pulled the line and caped it. There is another vac line of the same diameter that you can easily access when the TB is removed and it comes into the air intake just before the TB. The esisting hose didn't reach so I ran a new line from the PCV valve and T’ed it into this line.

Sorry for the little pictures. I forgot my camera so I used my phone.


PCV location and new routing.






I rented a scan tool from O’Reilly’s but it doesn’t show real time info, and it didn’t even sync up with the computer, so I couldn’t get some numbers for measuring the pre and post groove. His engine light was on, has been for a while, so there might be something that can be improved, but I couldn’t find out.

The customer doesn’t really track his MPG so that for now is a guess. But he does know how many miles he can go on a full tank, so after he fills up and drives a tank then we can get some MPG numbers.

We did a pre and post groove test drive. We pulled out onto the county road and he said, "Wow, that’s different." It was a good response because there was another person sitting in the back seat who was curious about the groove and if it really works. I will be grooving his Suburban next week because it was confirmed that – the groove works!

He said that it was like driving his car and not a minivan. There is more power, quicker pickup and the RPM’s are a bit lower for the cruising speeds. The person in the back seat mentioned that sometimes an automatic transmission will lock in a certain RPM for a certain speed. If so, that function would work against the groove. Can anyone shed some more light onto this subject?

Dan Grieve
South-Central Missouri

Hi Dan!

Did you reset the computer by disconnecting the battery cables, at least 1 hour, and ground out the positive cable. This will drain residual charges left in vehicle capacitors. Do this when you first start doing the modification - Step One, remove battery cables, Step Two, remove throttle body. The computer will then relearn fuel trims based on the groove and ALSO relearn transmission shift points based on new load parameters. Your posts are very encourageing - having a prospective customer in the back seat is great!

Keep up the good work!

Scott Castleberg
Pellston, MI
Gadgetman Michigan

He would be kinda right saying some use the rpms to shift but that is not all that the ecu reads as it cross checks through the maps so don`t worry it`ll be just fine. The groove gives more low end torque so the transmission issue would be null to worry about. Dan gadgetman Mo.