TOPIC: First groove experience

I got the groove about 2 weeks ago.I have a 94 nissan Pathfinder4X4. Waiting for improvement I discovered vacuum leaks in the throtle body. I discovered that the hex pinns holding it unscrew after a day or two, so they need to be tighten back. I wonder if I should use glue or not. One other issue is the seal on the throtle body, for which I could'nt get an OEM one. So I used RTV , that started to leak vacuum... Can any one tell me what RTV I should use ?

Hi Sandumunte, and Welcome to GadgetmanLand!

Pics of your work help a bunch.

Can you get a replacement TB Gasket from an auto parts store, or just cut your own from gasket material. Was original a fiber-paper type one? I don't advise RTV unless there's no other way. Were you saying the TB mounting bolts work loose? Deteriorated Throttle Body (TB) gasket is suspect as you said. Can't have any vacuum leaks, need to hunt those down and fix them.

RTV without any gasket will just smush out to almost nothing, don't want RTV going into engine. Won't break anything, but can contaminate O2 sensors and cat. converter.

Tracy G

Hi All, about the gasket leaking on the TB. Spanjaard has got a copper spray on the market, I,ve used it lots of times and is a favourite of mine. A bit axpensive but worth it over and over. I have used it on head gaskets with no problems. Why not?

Hey guys, about this gasket, and ANY TB gasket. The factory used a particular type for a reason.

In my experience, no "goo or spray-on type" stuff is a substitute for the real Thing. There needs to be something with substance or density that can compress. This allows the mounting bolts or nuts to hold their tension. Just putting RTV, Permatex, copper head gasket spray or whatever alone, well. I would not rely on that. Might work in a pinch for a short while, but a real gasket is needed.

If the original gasket was a fiber/paper type then bulk roll gasket material can be cut to fit. This is good to keep on hand. I've done that before and it does work. Another idea would be--just go get a new TB gasket ahead of time.

Unless you are in such a remote area that there are no parts stores around...then you must be self-reliant, or what are ya doing out there anyway...?

I used to use lots of RTV and various goo's on gaskets as dressings. Experience taught me when to use goo and when not. I stick to stock type gaskets now, goo is only for certain things and as a problem solver. Plus with goo/RTV there is cleanup issue if removing TB again.

That's my input, do whatever works!

Tracy G

I use 30 lb tar paper on the cable drive fords 4.2 4.6 5.4 no problems and its easy to mold and cut. I never use glues or silicone as it will confuse the ecu on some vehicles.





Dan Merrick

Great Idea, Dan! Tar paper (roofing felt?) Geez that comes in HUGE rolls, hafta 'member that one! Tracy G

Thank You all for the advice. I din't get any improvement in gas mileage yet, but the car seems to run better, to have more power. I checked the codes and all I get is , the MAF sensor runs OK, the O2 the same , and the mixture is OK. Weird, because if I take the air filter out, I hear a complete different engine, I hear the groove like a faint jet noise. So I tried to check and see how far the throttle opens, and surprise ! it closes and stays shut after 2000 RPM !
I wonder, from where does the air come from? Is it the IAAC valve? Is that enough?, because if it stays closed the groove has no effect!

?? Huh?? This is a cable-driven TB, right? Cant grok this.

Sandumunte, pics would be a BIG help on this. Ya need to explain this more. Are you saying it will hold a fast idle of 2K rpm, you're witnessing this w/ foot off the throttle pedal, or..?

I'd like more input here, I know someone w/ a '95 Pathfinder, so ya might give me some insight on this. BTW what engine is this, is there only one motor for these or is there a 4 cyl and a 6 cyl, etc?

Thanks!

Tracy G

Thanks
It is a 6 cylinder VG30E, it is cable-driven TB, and the only way I can see this, is when the engine is running and my son steps on it where I check it from outside, with the rubber intake hose off. It ran rough lately ,I thought it might be the gas quality , but then I said to myself it would be interesting to see how far TB opens. And it did in the beginning only to lock after it got to 2000, so I grabbed the cable and open it a bit to see what happens. It went strait to 3000 ! with just 1 or 2 mm opening.
So I was wondering how is it possible, where comes the air from, and how and when does the groove work...

First off if he steps on the pedal it must be opening the throttle plate on cable drive. When you take the air snout off if it has a mass air sensor it will run crappy as its getting false readings.

If not then it must be vacuum leaks,possibly the groove? Remember the throttle is only slightly open after the groove mod as alot more air is entering at alot less throttle angle. Ive seen 25 degree before and 10 degree after. It would be beneficial to use a scanner when doing the groove so you see the before and after and if you make this a business it for sure will help you show the customers.