Dipping revs when pulling up..
Dipping revs when pulling up..
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Merlot

Original Poster:

4,121 posts

231 months

Sunday 8th August 2010
quotequote all
What would be the likely cause?

Pulling to a stop either in neutral or with clutch depressed, the revs will dip to about 500rpm for a second or two, noticeably below what it should be (small amount of judder felt) before returning to the proper idle speed.

Car drives fine and is perfect in every other regard. Very low mileage '99 Mk2.


nikpro

127 posts

249 months

Sunday 8th August 2010
quotequote all
This can be down to the idle engine speed not being set correctly on the early Mk1 1.6.

Merlot

Original Poster:

4,121 posts

231 months

Sunday 8th August 2010
quotequote all
nikpro said:
This can be down to the idle engine speed not being set correctly on the early Mk1 1.6.
Mine is a '99 1.8 Mk2 ...

It'll sit at idle beautifully forever, it's only for a second or two when pulling up with the clutch depressed or in neutral.

If you depress the clutch when the car is stationary at idle, it won't do it - only when pulling up. It never cuts out and seems to do it both when hot and cold.




franv8

2,212 posts

261 months

Sunday 8th August 2010
quotequote all
A bit of a quick fix for this one (which admittedly bypasses 90% of the proper procedure) - flip the little black plastic cap on the throttle body (top left facing you as you look into the engine bay from the front).

Use a slot head screw driver and give it half a turn anti-clockwise. See if that sorts it out, if not, give it another tweak.

Idle speed control on these cars I would say tends to be quite weak.

CaptainSlow

13,179 posts

235 months

Monday 9th August 2010
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bluetone

2,047 posts

242 months

Monday 9th August 2010
quotequote all
CaptainSlow said:
^^^^ yes

Do keep up at the back.

hehe

Jonny671

29,763 posts

212 months

Monday 9th August 2010
quotequote all
Merlot said:
nikpro said:
This can be down to the idle engine speed not being set correctly on the early Mk1 1.6.
Mine is a '99 1.8 Mk2 ...

It'll sit at idle beautifully forever, it's only for a second or two when pulling up with the clutch depressed or in neutral.

If you depress the clutch when the car is stationary at idle, it won't do it - only when pulling up. It never cuts out and seems to do it both when hot and cold.
Yep, I get this too on my '99 MK2.. Not sure why, and as you say its only for a second or so then rises again.