FC - Limp mode and boost issues

[johnf]

Could do with some help and guidance regarding the ablove.

Few weeks ago my car went into limp mode.

Did the re-set through disconnecting the battery and brake route and that fixed it.

Went away for a long weekend and drove around 450mls, this was a casual weekend away so nice cruising speeds.

This trip took the engine through the running in mileage so couldn\'t resist giving it a bit of squirt - boost cut at 5k.

I\'ve checked the waste gate moves and not stuck, so I guess I need to fit a proper boost gauge to see if it\'s overboosting.

Today it dropped back into limp mode, some 500 mls after the last time.
Went back to it 30 mins later and it had cleared itself, but only for a bout two miles then limp again.

Got home and left it for 2hrs took it out again fine, thought I\'d see if the boost still cut out - it just paused for a split second at 5k and again at 6k -  decided that was enough.

Could these issued be related, better still what the hell do I do now?

I\'m trying very hard to love this car but it hasn\'t been a happy couple of years so far.

John

[grinder]

just side tracking on this , you say "running in mileage" have you had it recently rebuilt ?

[johnf]

Yes - Rebuilt be Carl, 1400 miles on the rebuild.

Any reason for asking or just interested?

[grinder]

I didn\'t realise that you had had a rebuild that\'s all

I would prob speak direct to Carl to be honest

[Prof]

Is it the stock ECU John?
 
If so it would be worth getting the ECU error codes just to make sure what the issue is.  There are a couple of things that can throw the car into limp mode, not just boost cut.

[TiddlesRX7]

As Prof says, Check the error codes and see what the car is throwing up. Hopefully something simple to fix. There is a write up on here of how to check the error codes if your not sure.

Ade

[johnf]

How do I get the error codes.
Do I need someone with a specific programme on a pc to plug in.

As far as I know it\'s a stock ecu

Thanks for the help so far

[GregR3]

Not sure but I think our FC\'s are ODB1 and will still provide some basic code data when you plug in a tester. Almost any garage will have a tester, luckily I live with JREX who has a state of the art SnapOn reader

Take it to a local garage John and share the codes on here

[grinder]

I have never even seen the ODB port on our cars .. where is that hidden away ??

[Mazzyrx7]

This is how I pulled the fault codes of my FC

You\'ll need to use the FSM for some of this. http://www.rotaryheads.com/PDF/2nd_gen/

To see what fault codes the car has stored. You\'ll need an analog multi meter to read the pulses from the ECU. Down near the battery and leading coil pack there are two green connectors. Ground the single one to the negative on the battery. Then plug the multi meter into the larger connector. One of the connectors is ground (top middle) then top left is positive and that is the ECU fault output. The bottom middle point is to test another control unit. Once all connected up turn the ignition on. Multi meter will display 3 second pulse then it\'ll display the fault codes. 1 long pulse is 10 (2 long pulses is 20) then you\'ll get short pulses, 1 pulse is one (5 short is 5) that code would = 25. The FSM gives all the fault codes in fuelling the part.

[GregR3]

I\'ve never needed to fault for codes on an FC but I was making the fair assumption that there is a port somewhere that will provide ODB data, and at the very least some CAN data. Upon doing 2mins of research online I came up with this..

"That\'s the easiest way to run diagnostics on the FC. The S5 is simple, just ground the green one pin test connector up by the leading coil. Then turn the key to the ON position. The check engine light will illuminate and then go out. Then it begins to flash the codes. A long flash is a "10", a short flash is a "1". It will flash any stored codes and then begin to repeat itself. To clear the codes, either disconnect the negative battery cable or pull the BTN fuse. "

This is from RX7 Club and so is North American, hope it works but says S5
and our cab\'s are S5\'s. Now you just need to interpret them with workshop manual or an electronic version on the net. I\'ve got workshop manual so I\'ll do my best to help..

[johnf]

For security I\'ve been pulling the EGI fuse overnight, this can\'t be having any effect can it?

[samgray]

Ring Carl before anything

[Mazzyrx7]

The problem with euro S5\'s is they don\'t have a check engine light in the warning light cluster, like the US car do. So you\'ll need an analog multi meter to pull the codes.

[Prof]

The problem with euro S5\'s is they don\'t have a check engine light in the warning light cluster, like the US car do. So you\'ll need an analog multi meter to pull the codes.

An LED works to - the code output comes out on a pin that\'s an \'open collector\' output, so the led needs to go between battery positive and the code output (oh and use a 12V led as it has the resistor in it).
 
There is no ODB (I or II) for these cars - the ECU is just too old!
 
But we are assuming John is running a stock or chipped ECU and not an aftermarket jobby