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OK,

so i have a 34, has all the china bolt on mods, high mount ffp power fc z32 afm 550cc denso etc

started, dropped the timing belt mashed valves etc

resolution, rebuilt the head

now, wont run properly,

symptoms

WONT start cold with out "start ya bastard"

missfires and stalls till at full temp

wont make boost unless i feather the throttle

hold it flat and it wont rev over 2400, or make positive pressure

generally wont run without great difficulty

im about to burn it to the ground.

legit, i have another er34 im building and this one just sits in storage, bad things are going to happen

any help is appreciated

Obvious question, if the heads been rebuilt and cams have come out etc i'd be checking that the cam timing (in terms of their relation to the crank and the other cam) is correct.

Sounds like the timing is out

If the AFM was dead it still should idle

Somebody correct me if im wrong?

But if temp sensor (ecu temp sensor) is open circuit, wont it just assume a standard running temp and it wont add cold start enrichment or cold start timing?

I had chronic cold start issues on a rb30et I used to own, would crank for 40+ sec before stumbling into life followed by 1/2hr of very poor running.

it was the engine ecu temp sensor, and it didnt run right.

To make sure take the lead off the water temp sensor (the one with two terminals) - ecu should provide a default cold start map (at least stock one does - don't know about pfc).

  • 1 year later...

If using a Cheap china ffp, could be worth checking the flange and pressure testing it....

http://www.sau.com.au/forums/topic/382409-rb25-intake-plenum-upgrade-rb26-intake-or-ebay-special/

Edited by AngryRB

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