solving the NB idle dip drama

EGG80X · Postby **EGG80X** » Sat Dec 23, 2006 10:17 am

Hey guys,

seem like the cause of my idle dip nightmare is oil vapur clodding up around the idle screw area..... so can a oil catch can solve the problem???
And extra engine bay bling wouldnt hurt at all hehe

I'll keep you guys posted when the oil catch can arrives......

JSE · Postby **JSE** » Sat Dec 23, 2006 10:18 am

My NA has a bit of idle dip as well. Keep us posted Kelvin, if it works I'll be getting myself a catch can.

JBT · Postby **JBT** » Sat Dec 23, 2006 1:00 pm

Have you adjusted the base idle properly in the first place?

Garry · Postby **Garry** » Sat Dec 23, 2006 7:00 pm

Have you adjusted the base idle properly in the first place?

ummm, yes. And spent quite a bit of time extracting the air bleed screw to clean all the passages used in the idle circuit at Bigdog's last dodgy day.

I'm guessing the dodgy day fix worked but it came back to haunt you eggbox?

I cleaned mine about 10 months ago and the idle dip is just starting to make it presence felt again, so a clean out every 12 months or so isn't to bad for me as long as I can get that $%^#ing screw out.

JBT · Postby **JBT** » Sat Dec 23, 2006 9:01 pm

Is this an NB problem?

The only time I ever had it was after a battery change. I check the base idle every 6 months now and it seems to stay spot on.

EGG80X · Postby **EGG80X** » Sun Dec 24, 2006 11:02 pm

Garry wrote:
Have you adjusted the base idle properly in the first place?

ummm, yes. And spent quite a bit of time extracting the air bleed screw to clean all the passages used in the idle circuit at Bigdog's last dodgy day.

I'm guessing the dodgy day fix worked but it came back to haunt you eggbox?

I cleaned mine about 10 months ago and the idle dip is just starting to make it presence felt again, so a clean out every 12 months or so isn't to bad for me as long as I can get that $%^#ing screw out.

yeh it did Garry, clean the throttle body last week and seem like it went away again..... Might try to clean all the earth/ground points as well

Garry · Postby **Garry** » Mon Dec 25, 2006 11:00 pm

Is this an NB problem?

Not sure JBT, but cleaning the the idle bleed screw and associated passages seems to help a lot in the NB's. Adjusting the base idle helps for a while but eventually everything gets gummed up to much and the idle circuit needs a clean out.

Unfortunately just spraying cleaner through the ports doesn't seem to fix it. The only way to do it properly is to remove the idle screw and clean it all properly. A fairly simple task but the idle screw has an O-ring on it that makes it very hard to remove it to clean it.

JSE · Postby **JSE** » Tue Dec 26, 2006 4:38 pm

JBT wrote:Is this an NB problem?

Don't know about the NA8s but I know many NA6s that have the idle dip problem.

rodent · Postby **rodent** » Tue Dec 26, 2006 5:55 pm

When the guacamole just sits there untouched.

zoomzoom · Postby **zoomzoom** » Tue Dec 26, 2006 6:05 pm

this problem has just made itself present in my na6. I thought it could be a sticky idle speed motor. Is there something else I should be checking? Its seems to idle fine except for when u just touch the throttle and let it go it drops before picking up slowly.

PS rodent, nice call

Garry · Postby **Garry** » Tue Dec 26, 2006 11:15 pm

MonSqueek,

Idle dip is when the idle speed drops below the usual idle speed, usually by a few hundered revs and only for a short time. Most times the idle system compensates properly and it returns to the correct speed. Other times it can over compensate and rev to fast, then to slow, then to fast etc until it finally gets itself sorted at the correct idle speed. In some instances the idle speed can drop so much that the car stalls when pulling up to a stop at the traffic lights for instance.

Normally resetting the base idle speed to the recomended speed will fix the problem. The base idle speed should be checked at the 10000 service intervals. In some cars the idle circuit gets gummed up with gunk and adjusting the base idle speed doesn't help. In these situations the idle circuit needs to be cleaned out before the base idle speed is set.

But i prefer rodents explanation :mrgreen:

zoomzoom,

Check your base idle speed first by jumping the TEN and GND pins in the diagnostic box. The recomended idle speed with the jumper in place should be on a sticker under the bonnet. You'll need to disconnect the battery to reset the ECU after you change the idle speed.

JBT · Postby **JBT** » Wed Dec 27, 2006 6:13 am

Garry wrote: You'll need to disconnect the battery to reset the ECU after you change the idle speed.

Why? Not part of the procedure for an NA.

Garry · Postby **Garry** » Wed Dec 27, 2006 10:30 am

Why? Not part of the procedure for an NA.

Thats news to me. The same reason you do it when you reset the timing.

JBT · Postby **JBT** » Wed Dec 27, 2006 10:50 am

The last step in both procedures (idle speed and timing) is to remove the wire bridging the TEN and GND terminals in the diagnostic box. There is no reference in anything I've read, including the factory repair manual, to disconnecting the battery.