Going to check over an rs500 tomorrow that is cutting out at around 4K. Goes dead apparently. Bit like a rev limiter??

First thought is phase sensor, poss even ECU??

Loose wires around distributor maybe at certain revs... or even engine management wires??

Could the crank sensor do this even?

Map sensor would be another port of call.

Any other ideas welcome - as will be doing a bit of head scratching I reckon???

 

crank sensor mate mine did exact same thing

 

aye was crank sensor on my 4x4 also....

 

Thanks lads - will take one with me

 

my mates cos had a bad misfire, it was down to the main pulley, that was odd! keep that to mind too

 

Ta, I even have a spare one of those - so will take that too

 

Could also be the tacho itself.
tabetha

 

Had a fun day folks - but not cured it. Crank sensor was actually cracked and looked like it had been damaged during engine refit or something. Thought - that's it but no!!!

According to the gauge (trust it???) she is only running 8lb boost but it feels like over boost to me now. Can get to 5 - 6 k in 3rd then momentarily dies - keep foot down and it kinda kicks in and out. Under less load in first gear etc. it can go nearly to 7K fine. Likewise if I am just a tad more gentle on the throttle I can get her to 7 in third.

Changed map sensor but no joy. Swapped ecu with another car and no different either. Actuator is new and wondering if it is the right one for standard as can't find any markings. Its wound back as far as poss yet we are still showing 8ish lb of boost.

Love cossys - they make your brain work!!!

Any other help or ideas please folks?

Andy

PS Phase sensor is brand new too.

 

how about testing the coil?

 

Andy

if you bridge the two bottom wires on the 3 pin diagnostic connector by the ecu with a paperclip etc the red engine warning light on the centre console will flash the fault code, let me know the sequence and I will look it up for you. This only works whilst the engine/ignition is on after the fault has happened, once you switch the ignition off the code is lost.

Sounds like a dry/corroded electrical connection in part of the engine loom to me, this will cause this kind of fault, swapping sensors therefore does not cure the problem

Good luck

 

Brand new coil too Kam. I also took the connections apart to check them. Paul - great offer mate.

Mine has its MOT tomorrow so fingers crossed on that - then I hope to get back to Bonkers car.

 

Is it a -31? If you take it off and look on the flat bit you can't normally see it might be written there. If it is it won't run less than 15psi on 1/2 eye pre load.

When you are testing it to get 8psi are you flooring it in 3rd from low revs? or tickling it in?

A way of testing what boost the car will run is using a footpump with a guage with the end cut off push it on the actuator and pump up and watch the arm move. This also helps when trying to get the actuator on and off.

Anyway why is rs500 running less than 10psithere's the main problem .

 

I think it could well be a -31 Dan. Love the foot pump idea - top tip mate

The car came in with an ecu with a chip for greens and 3 bar in it, but blues and a standard map sensor. As if it had been stage 3 at some point. That's why I am guessing about the -31.

Mark wants this one as standard as he can get... its only done 18K and yeah, I was flooring it to get 8psi reading on the standard tiny guage... flippin difficult to watch that and the traffic at the same time!!!

 

Yup makes it easy to get on and off. You have to remember to take the hose off to release the pressure.

Another tip for you is when your checking the boost (carefully) use the brakes much easier to load it up and give you a boost fig other wise you'll get a car that will overboost going up a hill.

Goodluck

 

Once had experience with a saph 2WD cutting out/missfiring around 4K. In the end seemed to be too much play on the distributor arm that goes into the bottem end. Took a long time to figure that out!

 

Yeah did that yesterday Dan. Not got back over there yet and may give it a miss until tomorrow. Its pissing down here so not the best weather to test an rs500 in.

Don't you just love Cossies, mine just past its MOT but on the way over to garage the red battery light came on and the fuel gauge and temp gauge dropped to nothing. Dash fuses are OK so something wierd happening there.

Altenator is 5 months old but lost one already due to overheating - first place to look I guess.

 

Thanks Wim, didn't know that, something else to fiddle with eh? Even though she is showing 18k some things are deffo a bit worn under the bonnet.

 

sounds like a fuel starvation issue to me.

check the vacuum hose on the fuel pressure regulator isn't split/leaking
check the state of the fuel filter
check the fuel pump wiring/voltage
check that none of the fuel lines under the car have been crushed by a trolley jack
fill the fuel tank above 1/4 full - if problem disappears, fit a new fuel tank

 

this sounds a little like the problem my dad was havin with his 3door when he was driving it and then slowly built the revs up it would rev upto about 6 and a half but if he were to just boot it it would go into a mad miss fire an start banging so he tryed changing different things and it never solved it so he eventually swapped the engine bay loom and it help a little bit but still payed up around the 6 6 and a half rev range so he change the coil and main coil lead and its been working fine ever since just needs a tune up now.. hope this helps mate

 

Hi Jon mate... unfortunately covered those things pal. New filter and pump were fitted with a new tray to boot. Voltage checked too.

Coil is new but not changed the lead Tom - ta for the nudge on that one.