Q's about switch on new FD(56k be warned)
 

It was just delivered this morning, along with being very dirty there are some things on it I have questions about.

First, what is this switch and what does it do...(I know it is aftermarket.)http://mywebpages.comcast.net/adammm/switch.jpg

This is zoomed out so you can see where is it..http://mywebpages.comcast.net/adammm/zoomoutswtich.jpg

Finally, to me this looks like someone has replaced my vacuum lines with silicone!.:)
http://mywebpages.comcast.net/adammm/engine.jpg

-Thanks for your help, and if you can point anything out for me in the engine that I didn't notice, I would appreciate it

The switch is the 3 position item that came with the Peter Farrell engine computers.
If you don't know whether your car came with that ECU, you need to pull that kick panel and see what is there.

In the event it is a PFS ecu, I would keep the switch on the lowest setting until you investigate the engine further.

Good Luck with it

yes, the first thing i did when i saw it was turn it to low.

-thank you

It might be a manual boost controller . high med and low boost pressure.

The PFS is a piggyback computer, so if you pull off the kickpanel, you'll see the factory ECU. It comes with a harness that is installed in between all the factory ECU plugs. Follow the wire on that 3 position switch to find the PFS unit (likely under the carpet in front of the passenger seat.

What other mods do you have? Your car looks otherwise stock, so there is really no reason to run that computer @ 10 psi (the "low" setting), and without reliability mods such as an intercooler and downpipe, i wouldn't run 12 or 15 psi (the "med" and "hi" settings) anyway.

If your car is stock, remove the PFS computer. If the body of the computer is gold, you have a very old outdated unit. Throw it out. If its purple, either sell it, or hold on to it until you have other mods that would require the additional fuel, timing and boost control that it offers.

BUT, beware. You have no idea how that computer has been set as far as fuel/timing maps, so simply throwing it on after a few mods could be disasterous. You'll need to have either PFS or someone who knows the EFI computer to make sure the maps are appropriate for your car.

WVRx7 is partially correct, and SomeGuy is partially correct. :)

It appears to be the 3-position (obviously) switch that lets you run high, medium and low boost settings with a PFS piggyback fuel computer (either their older "gold" computer or newer "purple" computer) in addition to the stock ECU.

The PFS computers came with a piggyback harness that plugs into the stock ECU, and the stock harness plugs are then plugged into the back of it, so that it can intercept and modify signals going into the ECU. The harness isn't exceptionally long, so the most obvious places to hide the "box" are behind the glovebox or under the passenger's seat. Peek under the passenger's seat, if you can, since that's one of the most likely places that it could have been tucked away. There's not enough room behind the passenger's kick panel for much besides the stock ECU.

Better find out which one you have and then read up on it. If it's the gold computer, I'd get it out of the car and limit boost to stock levels until you can get your stock ECU reprogrammed, or switch to something like the Power FC. If it's the purple computer, then you'll need to read up on how to program it, and get the keypad, if it didn't come with one. I'd still consider getting it out of the car though, I don't have an exceptionally high opinion of the PFS purple box either. :)

Damn Peter, beat me to it. :)

A couple of weeks ago I asked ernieT if he would come look at the rx7 I was getting shipped (we live very close together) and he agreed. I just have to give him a call. I bought it from a dealer that didn't have any history on it, so I don't know anything about its mods. He will most likely be able to tell me what is up with it. BTW, can u tell from the engine picture if it has had its vacuum lines replaced?

-thank you

yes your car has obviously had the vacuum lines replaced yellow was not the stock color and those are thick silicone it looks like.

They did a really good job too securing each end with a tie wrap! Maybe the motor was replaced?

Jeez your car looks really really stock. Only thing I see missing is the battery cover.

I have a stock ecu if you need

yea is there anyway i can tell if the engine has been replaced. I was thinking it might be becasue it has like 102,xxx miles and seems to run GREAT. Don't know about boost becasue the gauge isn't installed yet...gotta go to work.

I dug through my archives and came up with a picture of my first fuel computer... a PFS "gold" computer that I used for about a week before sending my ECU off to M2 to be one of the first guinea pigs for their reprogramming service in July of '97. :)

This is what you're looking for (gold or purple) and the picture shows the "piggyback" harness which inserts between the stock harness and the ECU, and the 3-way controller switch similar to yours.

https://www.rx7club.com/forum/attach...postid=1939088

This is what i saw underneath the passenger side carpet (attached pic). Its the purple PFS piggyback. What should i do? See if i can get ErnieT to look at it? Should I get rid of the piggyback computer?

O, sry if my post are annoying right now...too much excitement.:biggrin:

PFS ECU
 

Keep it on low for now !!

How does the car run ? BTW ?

i have never driven/owned an rx7 before but it runs GREAT to me. NO smoke anywhere, pulls hard, idles steady and perfect. If it has a rebuilt engine...i might lose bowel control. Its only problem (that i know of) is it needs a new paint job.

I guess my biggest concern would be why someone would go to the trouble of installing a PFS purple PMC on what appears to be a nearly stock car. It'd be interesting to know what the "real" history of your car is.

A fuel computer is not something you'd expect to find without associated modifications, and I wouldn't expect that someone returning the car to stock before selling it would leave the PMC in the car when they could have sold it... strange. Did your car come from a dealership?

Any idea what your exhaust looks like? Since your engine looks relatively stock from the top, I'm curious whether or not your car has its emissions equipment and what sort of cat-back is on it.

Like they said keep it on low setting. 4 years ago I knew nothing about these cars and had the purple box and tried the high setting. Car went really fast for 1/2 of the 1/4 mile and then popped an apex seal.

It was a theft recovery. The dealer said some bits of the interior were stolen and the headlight covers and gas cap. He replaced everything but one headlight cover and said that it runs great...so i thought good deal. Maybe this will help.

BTW thanks for the help

bit off top, but i'd replace that zip tie that secures the coolant line ti the thermostathousing with good clamps. zip zies are ok for vacuum lines, but i'd be worried about coolant-lines.

I don't think I would use a silicone hose there either.

This is the really big question... WHY?

I would hook up w/ a knowledgeable RX7 owner/tuner in your area (solicit folks on the forum or big list) and verify that you're stock on the bottom end: no downpipe or midpipe, and get a boost guage on it to verify the boost pattern.

If its stock, i reiterate my recommendation to remove the computer since it shouldn't be needed.

I'm sure there were originally enough aftermarket parts on the car to cause someone to go to the trouble of removing the passenger's seat to install the PMC, but it looks they're all gone now. The reason you ended up with the PMC at all is probably because it was hidden under the seat and carpet. :)

I'd guess that all or most of the go-fast goodies were taken which might have required the extra fuel, and the thieves just missed the PMC because of its location. The dealership (or someone) probably pieced the car back together with stock parts, and since they're liable in many states to certify that the car can pass emissions, I suspect you have a fairly stock exhaust system also, at least as far as the catalytic converters are concerned. It'd be interesting to know what's under the car, since it would fill in another piece of the puzzle.

At any rate, you likely have no need for the PMC at the moment, assuming your boost pattern is normal. Is there a boost gauge in the car? Personally, I'd make the best use of your find; carefully uninstall it, and sell it to someone else. When (and if) you do modify your car, I would recommend using something other than the PFS purple box for adding fuel unless you want to track down a keypad, you're really dedicated to learning how to tune one properly, and you have a strong desire to use 5+ year old technology. :)