Looking for a volunteer

[Tom @ Fast Forward]

Or guinnea pig, if you wish. :)

Thanks to the efforts of Bill (formerdatsun510man) we now have a new piece of software for the PC-Pros. My 05 used to run a bit rough for the first 2 minutes or so when cold. The new software makes the 05 driveable as soon as the engine starts and feels peppier when moving from off to on boost. It has always been smooth but power just seems to come on faster now.

The new software piece is like the old accellerator pump on a carburated engine. Anytime (off or on boost) that you move the gas pedal quickly, it gives an extra shot of fuel. It is just a little but it seems to work wonders. I would like to get a volunteer with an 01-05 Coldside and PC-Pros that would like to test it. Preferrably in colder climate. Down here a cold morning is in the low sixties at best. Let me know if you are having that cold morning hesitation and roughness and would like to test the software. I just need your PC-Pros and will re-flash them.

Thanks

[mx3jmcb]

Hey Tom,

Im unsure if its related to what you just brought up but my 94 runs very rough on startup in cold weather. Here in Canada, its about 32 degrees right now. The roughness lasts about a minute or so until the car somewhat warms up where it runs fine afterwards.

Would this issue apply to an NA miata?

JM

[zoom2xtn]

Tom and Bill

Can you collaberate on something for idle droop? I still have some; not as much as before I got the PCPro but if I let off the accelerator, push in the clutch pedal and leave it in without pressing the accelerator, the engine will die. Something is just not seeing something and doesn't know to turn the fuel on. If I have downshifted and let off the clutch it's OK.

Lee

P. S. Bill, I'll be in New Orleans Nov 11- 18 but have a full schedule. I assume the presidency of www.naepc.org that week. Meetings all day every day and dinners every night. If I get a chance I'll call you on your cell and maybe we can get together for a chat. We'll be working on a Habitat house on Saturday, the 17th until late afternoon so maybe Saturday evening might be a good time.

Everyone has to eat so maybe we could catch a Po' Boy somewhere. Had a muffaletta at Central Grocery last trip but I'm not a fan of the olives. ( http://www.roadfood.com/Reviews/Overview.aspx?RefID=122 )

Galatoire's ( http://www.galatoires.com/ ) is on the schedule this trip. Having a catered dinner at The Presbytere ( http://lsm.crt.state.la.us/presbex.htm ) one evening.

Last trip in January I hit Antoine's ( http://www.antoines.com/ )and NOLA ( http://www.emerils.com/restaurants/neworleans_nola/ )(Emeril was no where to be seen).

[Tom @ Fast Forward]

If you want to test it, send the harness to me and I will flash it and send it back. I think if you mark it "warranty return for repair and return" you might be able to save duties when it comes back?

The same software change would apply to all model years. Let me know.


Hey Tom,

Im unsure if its related to what you just brought up but my 94 runs very rough on startup in cold weather. Here in Canada, its about 32 degrees right now. The roughness lasts about a minute or so until the car somewhat warms up where it runs fine afterwards.

Would this issue apply to an NA miata?

JM

[Tom @ Fast Forward]

The best solution is a Coldside. :) Sorry, I just couldn't resist.

Have you moved the IAC off the DTB? That is #1 main cause of idle droop on hotsides.

Once you lift, the PC-Pro no longer has control of the engine/fuel. That is strictly the domain of the ECU. I am pretty sure we solved it on Chuck's hotside. Bill will have to speak for himself. All I can say about Bill's car is that, in the last week, we have his car running on a 130mm pulley and "It has never run this well before". His quote.

If you want to take a couple days of vacation and visit me, I think I can make yours run "almost" as good as a coldside. :) And I'll do it for free. Perfect time to visit Arizona.

let me know if the IAC has been moved from the DTB.


Tom and Bill

Can you collaberate on something for idle droop? I still have some; not as much as before I got the PCPro but if I let off the accelerator, push in the clutch pedal and leave it in without pressing the accelerator, the engine will die. Something is just not seeing something and doesn't know to turn the fuel on. If I have downshifted and let off the clutch it's OK.

Lee

[zoom2xtn]

I don't know! I'll have to let someone who knows what the IAC looks like tell me. I don't even know which is the real TB and which is the DTB but someone pointed them out to me once. I just don't remember. I know where to add gasoline, add engine oil and check to see if it needs any and that's about it. Maybe some day I'll take an auto mechanics class.

I will be in Phoenix in April "08 so I may just drive it to see some of the sights instead of fly in/fly out, even though it is 2000+ miles each way. I appreciate your offer. You are truly " a great guy".

In the meantime if I find someone to take the IAC off the DTB where should it go? Thanks.

I wish I had a coldside! Maybe you'll have the NC version ready and I can get one for the 2008 PRHT AT which arrives around Christmas. It's for my wife so the SC would have to totally transparent.

Lee

[Tom @ Fast Forward]

The IAC (Idle Air Controller) was typically (erroneously) mounted to the bottom of the DTB (Dummy Throttle Body). The DTB is located on the intake manifold. If you look at the front of the engine, there is a crosover pipe from the supercharger outlet to the DTB on the passenger side of the car. On the bottom of the DTB is probably the IAC. It also probably has a large hose coming out of it and going back across the front of the engine to the driver's side. This hose may or may not have a check valve in it. On the driver's side of the car is the Air filter connected to the MAF and the other side of the MAF is connected to a metal tube. The other end of the hose from the IAC is also connected to this metal tube. The metal tube is about 2.5" diameter and 6-8" long and may or may not have BRP cut into it.

If your IAC is like that, it is 90% of your idle droop problem.

[99mx5]

I picture is worth a thousand words... ;)

[zoom2xtn]

I don't know what an IAC looks like. I see the crossover tube from the SC outlet to the DTB -- mine includes an Intercooler. I see the hose coming from the bottom of the DTB (I do not know if it comes out of the DTB or an IAC as it looks all the same to me or maybe it's two pieces joined together - there is a line there that may be a joint)which hose goes back, passing between and parallel to the intercooler and the radiator,to the exhaust manifold side of the engine and connects to the metal cylindrical connector in the 3" hose between the truncated cone air filter and the intake of the SC. This cylindrical connector is about 4" or 5" long and has a connector out the side where the hose from the DTB connects. This cylindrcal connector is attached to (maybe it's all one piece) a bracket with the BRP logo that holds it in place with two bolts. (If I get cool-looking, good-sounding, stainless steel DDMWorks CAI box it will have it's own bracket to hold this cylindrical connector or whatever needs to be held -- there's a black plastic scylinder there too -- and I can lose the BRP bracket -- I think they just saw it off the metal cylindrical connector -- but they are still working on this product for this particular application.)

Is my problem that the IAC is at the bottom of the DTB instead of at the TB as it was originally which TB is now on the "hotside" instead of the "coldside" and the hose that runs from the DTB to the cylindrical connector is adding extra volume that the ECU does not expect and if I move the IAC from the DTB to the TB the IAC and the TB will be back next to each other as they were originally without this extra hose volume to mess up the ECU? I'm clueless but interested in learning. I just don't have much time to learn right now. Thanks. Lee

[dazooom]

Hope these help. These are pictures of an IAC valve on a "stock", 2001 intake manifold. The IAC valve is the part with the black connector attached to it.

[dazooom]

And here's the IAC that's been relocated for my hotside installation. (Lower left side in picture, sitting on a stainless block, and secured with 2 bolts). And has a gouge in it on the top!

[Tom @ Fast Forward]

here is the relocated IAC on Chuck's FFS hotside.

http://fastforwardsuperchargers.com/Install/IAC-Relocated.jpg

[chuckerants]

here is the relocated IAC on Chuck's FFS hotside.

http://fastforwardsuperchargers.com/Install/IAC-Relocated.jpg

That's what the relocated IAC looks like, but that's not my car. :)

[zoom2xtn]

dazoom, Tom and chuck

Thank you! My IAC is under the DTB. Now I've got to get it moved. The Mazda place here won't touch it. They even refused to make a factory emissions recall repair. I know it's the same as stock unless the SC gate valve opens under heavy acceleration but there is no sense arguing with a fence post. When I come to Phoenix in April I may drive my 2002 if I still have it. My wife says I have to sell it when the 2008 PRHT AT arrives around Christmas. We already have 3 cars and a 2 car garage so one is always in the drive blocking one in the garage. I need another garage.

Lee

[Tom @ Fast Forward]

Lee,

It's a relatively simple fix. When you come, I'll be happy to do it. I haven't heard Chuck complain about idle issues in a long time. Must work pretty well?

[chuckerants]

Lee,

It's a relatively simple fix. When you come, I'll be happy to do it. I haven't heard Chuck complain about idle issues in a long time. Must work pretty well?

My car now drives EXACTLY like I remember my STOCK car driving in terms of idle droop.

[Kyp J]

dazoom, Tom and chuck

Thank you! My IAC is under the DTB. Now I've got to get it moved. The Mazda place here won't touch it. They even refused to make a factory emissions recall repair. ......
Lee

If that recall is the ECM swap and TN doesn't prevent re registration like CA if you don't get it, don't get it. It doesn't help anything obvious and in some cases has been claimed to cause problems. I don't know if any of my problems was caused by it because I am the cause of most of them and I forgot what normal is but you will probably be better off without the recall.

[cmetzner]

Tom -

Is the reflashing only recommended for the 01-05 cars; I have a 99. The sc is off the car for the smogging. If it needs flashing now is the time to do it.

BTW - my IAC is mounted on the stock throttle body of my hotside kit and I still get some idle dip. It is there because I never upgraded to the BTB kit.

So, Tom, if I upgrade to the BTB, do I also get a dohinkie to mount the IAC in the manner shown in the photos?

[zoom2xtn]

What is the reason for the change in location of the IAC? Is it to shorten the distance between the IAC and the real TB so there is less volume in the connection between the IAC and the TB so the ECM sees the volume is expects to see?

Where is the optimal mounting location for the IAC?

Do I have to get a machine shop to fabricate a bracket like that shown on the car that is not Chuck's car? If so I probably have to get a flat solid plate and gasket to cover the hole under the DTB which will be left when I move the IAC, right?

It looks like the mounting bracket is L shaped flat metal with two holes in the top for "in" and "out" hoses to connect the IAC to somewhere. I assume the IAC is open at its top and mounts to the bracket so the two holes are both aligned with the open top of the IAC (there probably must be two chambers in the IAC and each chamber gets its own hose) so a leak proof gasket is probably called for. The two hoses go wherever and send and receive pressure or vacuum so the IAC analyzes the pressure or vacuum and uses the electrical wire to send a signal that tells the ECU to add fuel for idle. Am I figuring out this stuff? All I know about automobiles is where to put in gas and oil. Lee

[Kyp J]

What is the reason for the change in location of the IAC? Is it to shorten the distance between the IAC and the real TB so there is less volume in the connection between the IAC and the TB so the ECM sees the volume is expects to see?

Where is the optimal mounting location for the IAC?

Do I have to get a machine shop to fabricate a bracket like that shown on the car that is not Chuck's car? If so I probably have to get a flat solid plate and gasket to cover the hole under the DTB which will be left when I move the IAC, right?

It looks like the mounting bracket is L shaped flat metal with two holes in the top for "in" and "out" hoses to connect the IAC to somewhere. I assume the IAC is open at its top and mounts to the bracket so the two holes are both aligned with the open top of the IAC (there probably must be two chambers in the IAC and each chamber gets its own hose) so a leak proof gasket is probably called for. The two hoses go wherever and send and receive pressure or vacuum so the IAC analyzes the pressure or vacuum and uses the electrical wire to send a signal that tells the ECU to add fuel for idle. Am I figuring out this stuff? All I know about automobiles is where to put in gas and oil. Lee

Since I'm not seeing any responses from the "real" experts, I will give an interim comment on your questions. I am not sure why relocating helps with idle dip, just have to have faith since I have a coldside.

Tom should have the bracket available for sale at least if you aren't a customer of his kit.

The function of the IAC is to add or subtract idle air as minor changes in engine load tries to slow or speed up the engine. It is an air passage that just bypasses the throttle plate. The biggest load controlled is the Air Cond. The wires are input to the IAC from the ECM (computer) that moves a cylinder inside to open or close the opening as the ECM monitors the RPMs.

I relocated mine to the firewall near the windshield washer bottle. The reason I relocated was the bracket it was connected to broke off. It was subject to a lot of vibration in its original location. On a hotside I don't think that is the issue.

[Tom @ Fast Forward]

The bracket and IAC mounting plate are in stock. What I don't have is the blank off plate but that is available from Moss. I think this is the number "052-962 THROTTLE BODY PLATE, 99-05". Download my instructions for the 99-00 and you can see the mounting of the IAC and the brackets. The Moss manual http://www.mossmotors.com/graphics/products/instructions/999-810_999-811.pdf actually does a better job.

The key to the success of the IAC relocated is that in it's present position it is subjected to boost. It is never supposed to see more than atmospheric pressure. When remote mounted it works as intended.

[zoom2xtn]

Thanks Kyp J and Tom

Tom, I could not get the blocking plate to come up on moss or miatamania so I could not order it from them

when you have some in stock just send me the whole package (blocking plate, mounting bracket & mounting plate) and charge it to my card which you have on file or let me know and I'll PM you the card #, etc. I guess I'll need to get some hose, clamps and fittings but Advance Auto, AutoZone and NAPA are all nearby.

when I find someone to put this IAC relocation stuff on maybe I can get them to install the MP62 outlet and the auto tensioner which are sitting in the garage!! The Toyota guys (private shop) told me the tensioner would not fit but they are also the guys who could not hook up the 3 wires for the shift light. Whoever relocates the IAC can surely hook up these 3 wires at the same time.

I wish there were a shop near here that was experienced in Miata superchargers but no one knows anything about it. I can't find any individuals to do it either. As I look through your forum I don't see anyone nearby to ask if I could pay them to do it. If there is anyone on your list anywhere in TN let me know as I go to Memphis, Nashville , and Knoxville from time to time, also western NC, NW SC or SW VA are close enough for a Saturday work day. Thanks.

Lee

[bogey]

How about Cincinnati?

[Tom @ Fast Forward]

Lee,

I'll get some blank off plates in here ASAP and let you know. Not that hard to do. Once you have the parts, you can find a shop to do the change.

[zoom2xtn]

Bogey

320 to Cincinnati sure beats 2020 to Phoenix but I've emailed a buddy in Knoxville, 100 miles away, so I'd better wait and see if he can help with this.


Tom

I'll await your parts -- thanks for lyour help

would a drop ship of the missing plate here be any better? Prob. not as you are prob. buying several.

Lee