HELP - Timing and Idle problems

[driftMachine]

Hi, I'm having a bit of trouble getting my car back to base timing. A month ago I retarded it 3.5 degrees because I was running a FMU. Now I have a tuned ECU installed with 370cc injectors and so wanted to return the timing to base.

The problem I'm having is that I can't get the idle down to the 650 (+-50) rpms suggested by the FSM. Mine won't go any lower than 900. I have adjusted the idle screw all the way in and that's the lowest it will go.

I was frustrated so I set it at 20 degrees even though I couldn't get the correct idle. After hooking up the TPS again I checked the timing and it showed <15 degrees. Is this normal? I'm at a loss as to what to do and if my car is now safe to hit boost.

What could be causing the idle to refuse to lower? Is there anything I'm neglecting to do?

Thanks

[WDRacing]

Pinch the vaccum line going to the IACV and see if the idle drops or stalls. If so then I don't know why the IACV isn't letting you lower the rpms. If it doesn't drop the idle or stall, then you have a big vacuum leak.

WD

[driftMachine]

I found it weird as well. It did lower the idle but just not enough. I turned the screw in all the way, so I'm not sure if actually got stuck or it was actually in al the way. The lowest I could get it this was was 900 rpms. So I just adjusted the throttle cable to get the idle lower. It seemed it was maybe a bit tight causing the idle to be a bit high. Is this alright to do? As long as I had the rpms at around 650 I should be alright?

I did this before reading your post so I'll do the pinch test when I get a chance.

Thanks

[NateDogg]

The throttle cable should not be tensioning the TB open when released. You may have found the problem.

I would say if you can get the engine to 800rpm you will be fine to set the timing. The stock timing map is 15 degrees at 600rpm then 20 degrees at 800rpm. It jumps to 27 degrees at 1200, however.

[driftMachine]

Yeah, by adjusting the throttle cable I got the rpms down to 700 and then set timing. I should be good to go!

Thanks

[WDRacing]

Just make sure to pinch the big vacuum line going to the IACV. Or just pull it off and plug the end with your thumb. The car should die right away.

On almost any car, if you loosen the cables, the idle will drop some. Obviously the correct method is the IACV screw, but in todays world I''m a big fan of whatever it takes.

Make sure your TPS settings are now not messed up since you may have effected the low throttle signal by adjusting the throttle itself and not the in coming air. Thats the big issue with not using the IACV.

WD

[S13FX]

Oh one more thing.

Make sure you are taking your car back to base timing on the stock ecu not the tuned ecu.

And believe me it makes a difference I made the same mistake before and almost shot my self.

[driftMachine]

Oh one more thing.

Make sure you are taking your car back to base timing on the stock ecu not the tuned ecu.

And believe me it makes a difference I made the same mistake before and almost shot my self.

I put mine back to base on the tuned ecu. What difference does it make? What kind of trouble can arise from this? Seems to be running fine.

[S13FX]

Oh well if you got it running on the tuned ecu then your good to go .

I just had problems with mine doing it on my rom tune. But then again it was a SOHC, with a self socketed ecu and stuff.

All I can really tell you is, that me and one other friend had the same problem. But another friend of ours didn't have any problems setting timing with a tuned ecu.

I guess it all depends heh.

[driftMachine]

Oh, ok. Thanks for responding. Yeah, mine seems to be running good. I'm using a Redline tuned ecu and I really like it. I'll probably check the timing again this weekend to make sure, and also try the steps that WDRacing suggested.

Thanks for the help.