My DET idles like crap, it hunts when idleing at around 650rpm. vac gauge shows between 14 to 20hg depending on idle RPM, generally it will idle at around 650 and chase/hunt, with bad vac leak reading....

Sometimes after a run (boost up, then deaccel) it will divebomb right down to around 200 rpm then revs will come back up again, sometimes it will stall.

No its not the pop-off valve, because it does this with the stock valve also.

It's been like this ever since I did the conversion. We had a small fiddle with the metal screw on top of the AICV when we did the swap (7 months ago), I also had a play with it last night because I'm sick of it. (after all this time), no luck.

I also disconnected the TPS and ran it, I then played with a few minor different positions of the TPS on the TB... (adjusted it) as i had to use my DE TPS when i did the swap, ermmm..

Its basically got some kind of VAC leak, I just cant see where or how or why.

I know these kinds of problems can be a headache.

If I took it to nissan for them to look at do you think they could solve the problem? I guess it could get rather costly.

I might replace all the lines to the manifold / TB first.. then see how I go. It annoys me having to blip the throttle whilst at the lights to stop it chasing... every sucker reckons I want to race them or something! heh.

I also have bad chain noise, even when cruising. Should I try swapping out the tensioner first?

Thanks, James

iam having the same issue. I even recirculated and move the pop filter further away from maf inlet. These things helped but my car still dive bombs when coming to a stop. of course unless i "blip" the throttle. Under boost its fine its just driving in stop and go that sucks. Let me know of your solution. Iam currently getting some silver core wire and rewiring 02 sensor since mine dips to
low on voltage @idle. I was told when extending 02 its best to use the silver sheilded wire like the factory to decrease interference. So iam going to give that a try and i will let you know.

Im going through the same exact problem. I've been trying to find the culprit for a while now. So far, I changed my AAC valve, plugs and wires, most of the vacuum hoses around the TB, adjusting timing, and regrounding MAF. And as to this day NO CURE yet :mad: I will be checking my fuel injectors tomorrow. Anyone??
Nick

If you swap a JDM motor into s USDM car (no clue where Aussie cars fit in there unfortunately) I know you have to swap in the USDM AAC valve because the JDM one is different. The AAC valve is the thing at the end of the intake plenum with the idle screw in it.

Some say you have to swap this other vacuum line thingy underneath the intake manifold that has a 2 prong plug with a circlip on it. It uses about a 1/2" inner diameter vacuum hose. Ben Moses did not swap this on his DET swap a few years ago and hasn't had any problems, so I'm not sure that is true.

Oh- also there is a control valve of some sort that is on a USDM motor below the throttle body with vacuum lines. The USDM wiring harness has a plug for it and both JDM motors I swapped didn't have this, so I swapped that in too. I'd check to see if you swapped that in.

In terms of the vacuum lines in general, they are EASY to get messed up. What I did was ignore the vacuum lines when I swapped motors, then looked on my 92 SE-R with stock motor and see how they went and adjusted according to it on the JDM motor.