Hi there people, its my 1st post here, and i know the rules of most forums, so i have searched before asking, but im not really sure of what im looking for, so i come too you for advice!!
i\'m posting this on behalf of my friend, he currently has 2 FC rx7\'s (greedy eh!)
one is a UK, one is a import, and its the import we have problems with!
we was coming home from a night out the other morning, we got onto a b-road and opened it up, then all of a sudden we lost power, and all the lights came on (although it didnt stall) the went out after 2 seconds and then it was almost as if the car was in "limp mode" we got just by my house and it cut out.
we called the RAC, and his best diagnosis was dodgy fuel pump. having another FC at the house ment we could swap the fuel pump and check 1st before buying a new one.
this got the car running, but very very poorly, we limped it home, and there it sits.
so far we have changed the fuel filter, the coil pack, checked the sparks. and we can not come to a conclussion as to why it is running so rough, if it all!
if anyone could advise us on what to try next, it would be much appreciated!
thanks
Sean & Pat
I\'m assuming you reset the ECU to clear the error codes off?
Might be worth a compression test if you can get it to someone who can do one for you.
yeah compression test is our next action. i myself dont have a rotary, and my frieds knowledge is limited. so when we do a compression test, do you have any idea what sort of compression we are looking for?
thanks
Sean
You are looking to have 3 reading\'s per rotor (for each chamber) and should be something around 7.0bar. The readings should all be pretty similar and the rear rotor usually has a lower reading than the fromt.
If you get a reading of say 7.0 / 4.0 / 4.0 for one of the rotors then this could indicate a chipped/cracked/broken apex seal, 2 readings will be low or zero because it will leak into the next chamber if one of the seals are damaged.
I\'m not saying your engine is damaged but needs looking at to eliminate from the list.
really appreciate that mate! i will have a go in the morning, and come back with my findings!
Sean
Not sure if it will help if the car is running rough but this will also show up on a boost guage while the car is on idle - if the guage \'flutters\' then this suggest\'s damage to an apex seal too.
7.0 bar indicates a very good engine....you can go as far down as 6.0 bar...my fc TII had 6s all round and started and ran no problem and pulled good figures on the dyno as well. Youre looking for good high numbers and even numbers....although from what your saying it doesnt sounds like its an internal engine fault....have you checked your injectors? are you getting a good voltage at the fuel pump?
Hi, thanks for your reply.
The RAC fella suggested the fuel pump was faulty. i swapped pumps over from my other FC, and it still ran rough! when you say good voltage, do you mean through the plug? my mate pat is a good sparky and would be able to test this properly for me if so.
also, i have not checked the injectors. if you could point me in the direction of a "how to", that would be great!
thanks alot so far fellas!!
Sean
Has the map sensor pipe come off? its i little box on the bulkhead passenger side tube from the plenum, to check the voltage to the fuel pump, you need a digital volt meter,look under the panel in the boot, left side of spare wheel, unscrew steel plate with wires feeding through a grommet in the top, under there is the pump, with the ignition on you should (i\'m told get 9,2 volts test on the white/red stripe wire, and the neg connection apparently the voltage increases with load! the wiring on these cars are known for small gauge, my next mod is to double up on the gauge of wire, mine reads 9.2v when on tickover.that will tell you the voltage but not wether the pump itself is faulty, All the help is here somewhere matey, someone else will be along shortly, welcome to the club,
Good luck Bob
:2Confused
Experienced people cannot do a compression test on a Rotary correctly, but you guys are advising novices to do it!
Also there is no mention of what the car is... is it a Turbo or Non turbo.. so compression figures:Yawn , also no use in checking a Boost sensor just yet!
More information is needed on the car bud... What model have you got, Has it got a Turbo and what add ons or mods has it got?
Is it easy or difficult to start?
Where in Herts are you?
Thanks again for the replies.
the car is an FC3S Turbo 2. no real mods apart from a straight through exhaust.
its quite difficult to start, have to pump the throttle to get it started, which it will then run really rough, and as soon as you let off the throttle, it will die.
Im in hemel hempstead
Sean
HUMMM - i would certinly try the poor mans compression test
im not sure if this is 100% right bit
1 - remove the top plug out of a rotor
2 - remove the EGI fuse
3 - crank engine
4 - get someone to listen for 3 even PUFFS of air
5 - put plug back in
6 - remove other top plug
7 - crank and listen
if you dont get 3 even puff from each one then you "could" have problems
this is a free way of testing it
let us all know what this shows up and we can have a rethink
ta
stu
Did you try the Dodgy pump in your other car? (oviously don\'t hammer it, just on idle to see if it works)
I have to agree with Grinder (Thats sounds a good test by the Way ;)) but while your doing this have a good look at the plugs/Leads, you can usaly tell if there is a Problem as soon as the Plugs come out (e.g. if one rotor is soaking its plugs and the other is dry) also check the electrodes are Square at the end (if they are rounded off they want changing as its a sign there old)
I would also sugest you have a Good genral Look at Pipes Wires etc sounds daft but a mate rang me up to say his car has lit up like a Chrismas tree so he pulled over but could\'nt see and reason for it, so i went over and his Alt/Waterpump belt was Missing completly :)
If i had to hazard a Guess with a Decat pipe and it being late on (when its cold) i\'d say you have Overboosted.
Quote from: grinderHUMMM - i would certinly try the poor mans compression test
im not sure if this is 100% right bit
1 - remove the top plug out of a rotor
2 - remove the EGI fuse
3 - crank engine
4 - get someone to listen for 3 even PUFFS of air
5 - put plug back in
6 - remove other top plug
7 - crank and listen
if you dont get 3 even puff from each one then you "could" have problems
The three PUFFS of air should sound the same between the Front and rear (same speed and Volume)
Its not like a Piston where if you hear air being pushed out of the Plug hole its oviously ok, there are three baths per Rotor and what you are checking is each bath is sealed, if one Apex is down you won\'t get Air being pushed out on two of the Baths (so there will be a big pause between Pssssh Noises) This why its Important to check the Speed of the Pssh Noises, the Volume gives you an Idea of the level of Compression the Louder the better ;) but theyt should be roughly the same Front and rear.
As stu says its the Poor mans test but it works well at the side of the road and as Trex says to do a Proper compression test you need a Rotary Tester realy (there is other ways to do it but they are so unacurate that its not a good test and it only shows you if there is Comp there in the first place (plus you should never put any other Plug or Tester in without checking the Lenth of the threaded part, if it is not designed to be used in a rotary it may screw in to far and foul your Apex seals :eek:)
You say you are running with a straight through exhaust? If this is the case then following will be occuring when you give it WOT :-
Boost will reach anything upto 16psi when it spikes - rather than being capped at around 7psi. The engine will also be running lean in the mid-range, and I\'m surprised you have not had fuel cut from the ECU? IF you want to run with a straight through exhaust then you will need to fit a boost control device and have the fueling sorted. I\'d also recommend a fuel cut defencer.
What you described sounds like it suffered from serious det and put the ECU into limp home mode, if you still have no joy after resetting the ECU then its looking like you have damaged a seal I\'m afraid. (DId you see anything out of the rear view mirror? Smoke?)
BTW - A TII will run with the pressure sensor disconnected, it just means you wont get the right fueling....
Right with more info, I am sure you hit Fuel cut from over boosting...
The T2 suffers from boost/fuel cut as soon as you crank the boost... and it comes on rather violently and Harsh.. :eek
This could cause problems... if your engine is not strong..
So it now looks like 2 things. You are in a limp mode with the ECU.. or unfortunatly it sounds like internal damage..(which it really sounds like to me)
If you are desperate, I am not too far from you and can possible pop round to have a look at it for you sometime next week...