[monley]

Sitting In traffic today causing along 1st gear at 1500rpm the engine would surge every 10-15 seconds and drop down in revs creating a bunny hop effect. The car idles fine and cruises fine at any sort of speed but just below 2000rpm this surging happens.

I've replaced the leads and plugs which made no change. Where to go from here?



Cheers,

Andrew

[azzas15]

Mine is doing something similar but it's not affected by the gear. Mine will sometimes just cut out and no power at all then I just tap the throttle and it comes fine. It only started after I got a new exhaust.. I was thinking it was just a dirty sensor somewhere.

Good luck finding your issue

[JrZook]

Try re-bleeding the cooling system and if it still plays up you should try cleaning the cooling passages in the throttle body

[monley]

How does that alter revs? I don't have any sensors feeding information from the cooling system to the ecu

Speaking of ecu's I have a spare one kicking around, might try that out

[SierraDan]

Coolant doesn't run through the intake system?

[DarkHorse]

Sticky TPS or idle stepper motor?

[JrZook]

SierraDan wrote:

Coolant doesn't run through the intake system?

On Vitara G16Bs coolant runs through the IAC (idle air control) valve on the throttle body, well at least the earlier ones.

Monley: I believe your G16B runs a ecu/water temp controlled IAC. Needs to have clear coolant passages and no air in the system to work 100%

Have a look in this thread for more info
http://auszookers.com/forum/viewtopic.php?f=5&t=5117

[monley]

And the culprit is (insert drum roll)...alternator

I had a feeling my alternator wasn't charging the battery to which I fiddled around with the cables on the back of the alternator with the volt meter on the battery and watched it go from 11.6 v with the engine running to 13.8v(after I found the loose cable), then when I increased the revs to see if it went into the 14s, then the surging started with the volts dropping down to 6v, 8v then 12v then it would keep doing that until it got over 3500rpm. So the dizzy wasn't getting the 12v it needed.

Thanks guys

[jason_sgt]

I had an issue with my TPS causing same symptoms. not faulty just needed adjusting. Glad its sorted!

[monley]

New alternator fitted and it's running like a dream now