jay030787

Hi don't no if anyone has any ideas but I habe cosworth management on my rs turbo and it runs but really badly when the pressure is set at 3 bar. so I have lifted it and lifted it and soon as it hits 10 bar it runs absolutely spot on but it cannot run that high as it wo Kill my pump what could be my problem

Rob_DOHC

iTrader: (4)

Honestly, I hate replies like the one I am about to give but I think its the right answer here.

Take it to your tuner, someone familiar with the unique quirks that cosworth management can have.

If it does drive, be really bloody gentle. It could be something simple, a coolant temp sensor has a huge impact on the amount of fuel injected, you are very lean at the moment. Does the car run better when its warmed up?

Rob,

jay030787

Not really haven't had it running for to long as don't want to damage it and I will check the temp sensor my problem is everyone who deals with them are so far away so want to do as much as I can myself

jay030787

Just tested resistance of the temp sensor and its 4 degrees at work and its reading 8.25 ohms

Rob_DOHC

iTrader: (4)

Are you sure its not 8.25K ohms?

At 10deg C the resistance should be 6 Kohms for the cosworth coolant temp sensor.

If it is genuinely 8.25 ohms then you have found you issue, the ecu thinks the engine is at over 150deg C and the mixture will be desperately lean.

Do you have any resistors? A quick test would be to place a 10K resistor across the coolant temp sensor connector with the sensor unplugged. If the car runs properly then the sensor is certainly your issue.

Rob,

Rob,

oldford

If you measure 8.25 KILO ohms, that sounds about right for 4 degrees Celsius.
8.25 Ohm is way too less, even at 125 degrees Celsius you should still have 100 Ohm.

You could also measure voltage of the coolant temp. signal.

Karlos G

iTrader: (4)

As Rob has said it's very very lean if raising the FP to 10 bar makes it run well!
Coolant sensor, poor wiring to the injectors (low voltage/poor earth), MAP sensor faulty or again it's wiring.

jay030787

Ok after testing the coolant temp sensor looked like it had pushed the wire out of the back of the plug now it runs a lot cleaner the only thing is now when you hold it in revs or tickover after 3-4 seconds it try's to stop if you quickly blip the throttle it keeps running so you have to keep blipping it or or cuts out any ideas

studabear

Idle valve plugged in and working, is the tps set correctly?

jay030787

Yes it's plugged in and it's new so would think its working and throttle position is reading 5 on tickover the dropped when you open the throttle so looks right

studabear

have you got a engine monitor to be reading the tps position?

jay030787

I used a multimeter