Weird Rpm Problem At Certain Speeds

[tiesto]

Hi guys

Ever since I bought my r32 rb20det I get this weird problem when driving and only recently I found the symptoms of it

Sometimes when I start it (cold start) I have to tap the throttle to get the revs up then it idles perfectly with no problems and warming up is fine

When im driving at like 60kmh in fifth gear I put the clutch in and the revs go all the way to 0rpm and battery light comes on etc, but if I tap the throttle it the revs would go up accordingly and then get back off the clutch it will come back to life as in the revs would be back to normal

Is this something to worry about?

Sometimes also at low speeds, if I'm on the clutch and I apply the brake really hard to stop at intersections it does the same thing and the revs die to 0rpm and all lights come on, but then tap the throttle or clutch out and it kicks back itself again...

Could it be some sort of leak somewhere?

Any advice would be appreciated

[Craved]

sounds like the atmo BOV over fuel issue to me..

[tiesto]

i dont have atmo bov? i'm running stock bov with stock piping at the moment

[Craved]

then it could be an inlet leak from a split vacuum hose or injector seals, you can test for this with a can of degreaser/rp7/WD40/carbi cleaner - if there is a leak, then the spray gets sucked in and the engine revs will rise as it burns that fuel..

give it a try on vacuum hoses, injectors, between the upper and lower sections of the plenum etc etc

[Mr Italy!]

Check the wires that connect to the ECU. Check that the plug at the end of the ECU is fully tightened.

I had a similar problem, tightened the bolt and it was all sweet after that.

[tiesto]

thanks guys will give it a go

yeah i sprayed before just near my plenum i had a leak there on inlet manifold

i have changed my inlet manifold gasket because inside cylinder 5 and 6 air was choking a bit there and its all fixed now so no more severe idle problems, like the car is driveable now but just if you jump hard on brake or clutch in the revs will go down severely but then kick up again

[Craved]

you ever have starting up issues?

loose connections to the battery terminals can cause issues like this also double check the voltages out of the alternator as well

[tiesto]

yeah start up issues on cold

when i start it on cold without tapping the throttle it is hard to start

i have had my alternater reconditioned so it's like brand new

on my apexi pen timer it shows 12.2 - 12.5 volts on the battery but the reading also flashes indicating it is also at low voltage

i'm planning to buy a new battery soon but there is no problem with it being charged

[Craved]

another thing to try is adjusting the TPS a little . bandaid fix though.

[inissane]

i have this same problem its really pissin me off gota get to the bottom of it now

stalls coming up to lights on clutch in/brake and have to heel toe blip accel to keep it alive, starts 1 in 5 cranks too

ive sorted the battery, coil packs, plugs and wired fuel pump to 100% duty (040 just making sure lower setting wasnt causing stall) and no love

next i guess ill check afm, aac, injectors :

[tiesto]

yeah my problem seems identical to yours inissane although my car is driveable only when i get on the brake hard with clutch in it stalls but then comes back

also hard to start aswell like you said

i might try battery

ive changed afm aswell

and ive cleaned aac valve ;p

i wired my fuel pump aswell to the boot so it bypasses the ecu (could be the problem?) i might change that back this weekend

will post results