Hi, im completly new to the mazda rx7 rotary engine and living in england theres not many mechanics at all that specialise in the rx7.
Ive had the car about 3 weeks or so, havnt drove it in a few days. Started her up this morning to find that she would only rev to 2500rpm nothing more. She idles fine but when in neutral and i put my foot down only revs to 2500 rpm. Its like the rev limit has set itself to 2500 rpm.
Any idea why? Is it an ecu problem? Fueling problem?

Cheers

 

2500rpm on warmup? or even after warmup??

its going into AWS, this basically revs the car to around 3k to warm the pre-cat up..

start the car in 1st with the clutch in, it should start up normal..

 

If i turn the key and start the car it idles nicely at 900rpm but if i try and put my foot down it revs but only up to 2500 rpm. I can drive the car but not over 2500 rpm.Wether the car is warm or cold it doesnt go over 2500 rpm

It doesnt idle at 2500 rpm if thats what you thought i meant?

 

its a 92 rx7 totally standard apart from an aftermarket exhaust system.

 

it might be an ecu problem.....it seems like ur redline or revlimit is set at 2500. Fuel problem wouldnt do anything like that, that I know of. What other mods or features do u have on the car?

 

try resetting the ecu

 

Is it bouncing off the limiter, or just stopping at 1500?

 

Ok, I'm not sure how things work in the UK as far as years go, is it an FD or FC (3rd or Second generation)

 

Sounds like maybe you have a Apex PFC or some other adjustable
EMS with its rev limiter set at 2500 RPMs..

Many people do this when they take their car to a shop.
So the grease monkeys don't go on joy rides..

open up the passenger side kicker panel.
and look at the computer.. look for a an aftermarket Logo..

If you have a PFC< you will need a commander to put you rev limiter
back to normal. or 8.5K rpms..

goodluck

 

Ok, you said 92 rx7, but I'm assuming that you meant 93.

As for your problem, it sounds like your ECU (assuming it is a stock one) has gone into limp mode. This happens when it gets certain codes (such as an injector not functioning for example).

Try jumping the TEN and GND in the diagnostics box and checking the check engine light for trouble codes. Then look them up on here. If you don't get any codes, disconnect the ground to your battery and hold the brake for about 30 seconds to reset the ECU, that should take it out of limp mode if there are no serious problems.

Do you have a boost gauge installed? Limp mode doesn't limit the revs to 2500, it cuts the fuel when the manifold begins to have positive pressure, but it usually hits positive boost around there.

-Charlie

 

who wants to say it with me?

....





LIMP MODE!!!!!

disconnect your battery. hold down your brake pedal for about 2 min (30 seconds is the standard, i always hold it longer to make sure) then reconnect, start, and drive. should be fixed.

 

yeah it was in limp mode. an easy fix
Does anyone have any idea what would have caused it?

Cheers for the help

 

Should have checked the codes BEFORE you disconnected the battery.. Odds are though it will just jump back into limp mode if you didn't fix anything.

 

i knew it was in limp mode.....

 

yeah it does keep going into limp mode how doi check the codes?
cheers

 

there is a diagnostics box the driver's side (US spec drivers side) open it, there should be a picture of the pin identifiers.... connect the TEN pin with the GND pin with a jumper wire (with the key turned off) IIRC, The ten pin is the very top row 3'rd from the left, and the GND is the 1st pin on the second row..... then turn the key to the ON spot, and watch your check engine light, it'll flash long lights for the first number and fast lights for the 2nd.

 

That was said in the first page. Check your codes and go from there. Possibly you have a omp going bad or just a injector out of specs.
Thanks Robert

 

right ive tried checking the codes by connecting up the ten and gnd but when i turn the key in the ignition i dont see any flashing engine lights???
i reset the ecu yesterday and left it running for a minute but went to drive it and it had gone into limp mode again

 

There are a quite alot actually mate:

RE:Worx
Dragon Performance
Hurley
RX Motors
WGT
Hayward Rotary

Those are off the top of my head, there are a fair few more too. Give one of them a ring, I'm sure they'll be glad to help.

 

I'll give the thumbs up to Dragon, they did a top job on my car...have now since started to learn the ways of the rotary FD so hopefully will be easier on the pocket.

My advice is to give diagnosing the fault your best shot - without knackering something up of course - as in the long run you'll save yourself a lot of cash.