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hey everyone

i have a problem with my engine again (RB20DET silvia)

as some of you know i took it out to the track day at qr last week

car was fine until the end when i lost power.

I thought it was intercooler piping but got back to the pits and found out it wasnt

Eventually got her home but with a lot of effort

It was very boggy in low revs and then a little less boggy in higher revs.

Got it home and now it wont start, it is cranking but not starting

we have tried:

  • battery voltage is fine, brand new
  • spark plugs
  • coils are fine (coil leads are sparking spark plugs)
  • above point rules out wiring and ignitor
  • plenty of fuel in the tank
  • taken the exhaust off before the cat to make sure it hadnt clogged
  • clutch-starting doesnt work
  • fuel pump makes it usual whine on start-up
  • injectors seem to be fine, fairly decent smell of petrol in the engine bay
  • vaccum lines all checked. fuel lines are fine. fuel filter is fine.

so what else does this leave me with? crank-angle sensor? anything else?

your help would be very appreciated :thumbsup:

Edited by Sammy
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my guess is AFM if you have one

or the ecu is playing up i.e not grounding properly

Andrew

The motor should still start without an AFM, but it'd run like garbage, with lots of smoke, highly unstable idle, etc. And if you have spark, the ECU should be fine. Happy to be corrected on that one though.

Spark, fuel and compression is all we need. Sounds like you've covered all three bases already. As Adam said, plugs will foul with fuel, and it is probably flooded, but WOT whilst cranking should sort that - and the boggy performance you mentioned means it is something else.

A dodgy coil or a fouled plug or two will start start, but just run like crap. Sounds like spark is covered.

When a fuel pump dies, the motor will start for *just* a second or two and then kark it. One or two blocked injectors will start start, but again run like crap.

Sammy what you've described seems like a vac leak, just like you thought. Is there any chance you could have missed something?

Mark

ok guys well the update on the sitution is unfortunitly not good - she is STILL not working :(

Today we did:

* tried a different AFM

* new spark plugs

* cleaned AAC valve

* checked all vacuum lining

* Adjusted CAS with hand to see if that did anything as suggested but didnt make any difference.

* sprayed all connections with contact /electrical cleaner

We can gather that the engine is getting more than enough fuel as the spark plugs get flooded with fuel not long after putting them in

Sparkies are still sparking and the car is still cranking but NOT starting.

So basically guys i mean we dont think the engine has popped but it is definitly getting fuel, spark and air so i dont know where to go now

would getting a new CAS be on the cards???

Any pointers would be really helpful guys :):D

its much appreciated!!!!!!!!!!!!!!!!!!!!!!!!!

thanks so far for all ur comments - KEEP EM FLOWING!!!! :D

Sammy :)

Edited by Sammy

yes i would try a CAS if you can borrow one to test with. Then try a fuel pressure guage to know if you do have correct pressure. I have had a blocked return pipe and got huge pressure which resulted in loss of power, fouled plugs and then no starting

As i replied on ns.com

Try this, once u try to start the car twice and it just wont start, remove the fuel pump fuse, and the car SHOULD start, when it does, within 10 sec replug the fuel pump fuse back in.

What you are describing (and what you have already tried) sounds to me like your water coolant sensor is gone. It causes your ecu to missread the info being fed into it, thus it will make the car run heaps shit/not at all

If you are absolutely curtain the engine is gone (based on your initial comp test), just invest in a new water coolant sensor.. its only like $70, try it, u may save $$$$'s

Good luck :bunny:

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