I just changed engine loom in 3 door cosworth . I couldn't start after changing loom so I changed everything sensors / coil /ecu /map sensor/ etc I eventually got it started but tps was set wrong and at idle positon resistance across tps was gone off scale .I adjusted tps but idle is now around 2500 at idle .obviously this is too high and I need to readjust tps however iscv is now clicking rapidly like an injector does .what could cause this .car will drive fine power is fine but rev counter jumping around .if I unplug iscv car runs better but revs still around 2500 rpm .

 

If the ECU see's the TPS out of line it opens the Idle valve to eliminate throttle by the driver and will continue too until TPS is correct.
http://www.bigturbo.co.uk/
go into faults section.

 

paddy check that the wires are in the right position on the tps as that loom may have being made for a level 8 where the wires are opposit in the plug

 

As above, and check your phase and crank sensors if the rev counter is jumping around.
I can't remember which one drives the rev counter off hand.
check the gaps and the wiring. Its not unheard of for the pins to come loose in the plugs and get pushed back when you plug it in

 

Neither do, the rev counter is from the coil.

The TPS is open circuit at idle, the ECU uses this signal for the idle and overrun strategies, now you have tampered with it, this may not be the case anymore! Also as said if it's a 4x4 loom you need to invert the outer TPS wires.

Martin

 

Thank guys I just seen replies . Will check tomorrow !

 

Ok I'm glad to say car running perfect . I gapped everything again crank sensor ,phase sensor and plugs . Set up throttle sensor position and swapped the two wires on throttle sensor and bingo ran perfect just revving hi so I tried to adjust base idle screw and couldn't get it below 1500 and rev counter was jumping all over the place . I then changed my group a coil for old coil and bingo perfect . Thank fuck this has been wrecking my head for last 5 year

 

Thanks everyone for replies these cars can really wreck your head sometimes !