Sr20 Issues

[bigm]

Hey Guys

Uploaded a video that best shows whats happening - http://www.youtube.com/watch?v=UEMcC1Kt0Lo

If i start the car cold its fine, then idles fine untill you touch the throttle. then it hunts like in the video..


Engine info

Sr20 DE + t
Redtop ECU and Loom
AFM - ran on another car fine for a period of time.
TPS - set to .46 volts (couldnt get it any closer, had the same issue on the auto TPS when it was DE)
Injectors and coilpacks working fine (Turbo injectors)
No o2 sensor in dump
IACV had no water lines on it, put water lines in today, has not had any change.
ECU - have tried 2 different ones.


No Vacuum leaks as all lines are new but may not be related - I have removed the line that goes into the rocket cover from the inlet manifold. and now on the exhaust side of the motor the lines are vented into the atmosphere, i have the intention of running this into a catch can. or is this the incorrect way for going about it?

I had the same issue when the motor was DE with a dizzy.

Any help appreciated

[H8CHIR6KU]

that link didnt work for me

but just going from what you wrote i am thinking coolant temp sensor or you have a hose clamp loose or piping come off on your intercooler piping. but seeing as you said you had the same thing when it was DE
i am going with coolant temp sensor

[bigm]

yep coolant temp sensor seems to be popping up a bit, will have a look during the week.

updated the first post with working link

[Nicko]

Definitely a sensor or something like that.

I would be checking wires and sensors to the AFM first.

And then at the ECU end as well.

[Gunner]

clean the afm with, contact cleaner, then clean the thottle body, and idle valve with carb cleaner, then if it doesn't work start looking for a dud sensor.

[Nicko]

Check wires to TPS also.

Could be a dodgy TPS

[resol]

the SR and most nissan ecu's are 'learning' ecu's, so if the ecu has had no power for an extended period or been reset then it has to learn the system all over again and adapt to the style of driving etc. sounds like it might be searching for mapping points to set base timing and idle. let the car run for maybe 5-10 mins and see if it settles down, but dont rule out dodgey sensors etc. the coolant temp sensor sets a high idle so if its not working properly and sending pulse signals instead of continuaous then it could be adjusting the idle inconsitantly. there is also the idle control valve and speed screw which can get dirty and screw with the idle, though it usually idles low and stables. check and clean it anyway, its in the middle of the intake manifold looking straight up -a small white plastic phillips head screw- get some carby cleaner onto it.

my money is on the ecu searching for mapping points though.


-dan

[FAST EDDIE]

id put my money on a vac hose somwhere, my gfs s13 did the exact same thing with one connected incorectly. does the car run properly undoer power?? have the idle control valve setup connected still?? try sealing ti off???

[bigm]

Nicko - it has had a different loom and ECU since being converted to DET. Was running a de loom before hand. have inspected the loom with no visual problems and no resistance issues as of yet. Also changed from auto to manual TPS during the conversion, and has the same issue DE. TPS has been set within range using multimeter.

Gunner - by removing the TB and cleaning it, willl do.

Resol - As above, the issue was there when DE and i ran it for 8 hours at the track and the issue did not change.

Eddy - ICV is plugged in, if its blocked off the motor doesn't run.



So next strat is to:
-Clean TB
-Test Coolant Temp Sensor somehow.

will sus that.

Thanks heaps for the replys guys

[FAST EDDIE]

i dont have it on mine or klingbergs ke70 wagon and they both idle fine so maybe block it off and just adjust the butterfly open a little, mine runs perfect without it!!!! its just something extra to fk up! id still put money on teh fact you have a vac leak somewhere cos thats exactly what srs do with one split hose or something!!!!

[bigm]

yea ill have a go at the ICV if i have no luck testing the coolant temp sensor tommorow.

where abouts is the screw to adjust the butterfly? havnt seen one, but havnt looked at all.. or is it done by tightening the throttle cable mount?

[FAST EDDIE]

nar its the screw that the butterfly stops on, 8mm locknut and hex key bolt

[bigm]

alright to easy will sus it out tommorow in the day night..
Cheers for the help will report back

[Hokey]

does the ecu give any codes?

you can google all the resistances for the sensors too

[bigm]

all the sensors were within spec.


I removed the IACV that goes to the IC piping and we have a winner. thanks for the advice eddy. well ran the car for 10min and reved it a bit, no problems at all and thats when the issue started before.

Thanks guys

[FAST EDDIE]

winner winner chicken dinner you can rip the whole unit out of the manifold and just plate it if u want 10 grams less weight lol

[bigm]

yea was thinking of that, but would be easier to seal with the unit on and a stopper on the pipe. that 10g would make my car tho

cheers again

[bigm]

ok
WTF
issue is back.....

went for a drive. did a lil skid. after the skid, bang, really high idle (guess around 3-4g) no tacho yet.

shut the car off, idles lower but does the same thing as before.

IVAC is still blocked off....


WTF!

[FAST EDDIE]

tried changin ecu and afm??

[bigm]

i think afm, but had no issues when it was on my mate car for a track day. thats whats got me beat.

also ecu happens on another one. so yea....

grr might just take it to a tuner and he can sus it out.

anyone got a diagram of the vacuum lines? might have them the wrong way around with the ones above and below the TB....

[biggo]

It sounds like a vaccume related as you drove it and then its come back.

[bigm]

yea. ill sus it when im back from perth.

gona pull the manifold off and do it all again, new lines and try and find a sr manual so put them as factory...

[FAST EDDIE]

where are they going? only one you realy need i a line for the fuel reg, take a pic?

[bigm]

on top of the tb - one to fuel reg and one to boost gauge
bottom of the tb - one to turbo wastegate.

[FAST EDDIE]

MAYbe if your pcv is not working properly then its letting vac in intermitently!!!! when the gasses are warmer,

[bigm]

the PCV, are you referring to the fitting that screws into the back left hand side of the rocket cover and has a line into the intake manifold? if so. the issue was still there when i had it blocked off....

also possible. i removed the box on the exhaust side of the block that goes to the T piece in the rocket cover, just ran the hose straight from the block to the T piece instead... bad?

other than that, the hose from the other side of the PCV goes back into the intake pipe after the AFM..

thats pretty much all the vacuum lines on the car hahah


has to be a dodgy sender, would a 02 sensor being removed cause an issue?

[FAST EDDIE]

nope that like a cruising fuel economy sensor

[Nicko]

does the ecu give any codes?

you can google all the resistances for the sensors too

For Fast Eddie : Did you even bother with this ^^^^^ yet ?!

[bigm]

cant test for errors as the loom as been modified to go in the cress.

have set tps and check coolant temp sensor with no abnormal results. so yea.