Golf mk2 high revs

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Wed 1 Dec 2004 13:12
Golf mk2 high revs - Al Civic
I have a golf 1.8 which idles at 2000 rpm or above for a very long time, in cold weather it can be as long as 10 minutes. It will then return to a normal level quickly, 1000rpm, after hearing a click in engine compartment. The temp gauge looks normal, often the temp has to climb to half was before the revs return to a normal idle. Often the fan has clicked in at this point.
If the car is taken on to the motorway the temperature gauge looks normal but once you come off the motorway the revs are again 2000 rpm.

Does any one have an idea what could be causing this.

Thanks Al
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Wed 1 Dec 2004 14:39
Golf mk2 high revs - mattieboy
Hi Al

Is it a constant rev, or does it bounce between idle and high revs? I had the 'bouncing rev' problem, turned out to be temperature sender.

Matt
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Wed 1 Dec 2004 17:18
Golf mk2 high revs - Phil G
It's your carb. Search this forum for pierburg 2E2 - lots on information. Easiest fix is to swap it for a weber replacement, but this is about £200.
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Wed 1 Dec 2004 17:24
Golf mk2 high revs - Big Cat
...and you must inform your insurance as it's classifed as a modification.
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Wed 1 Dec 2004 18:17
Golf mk2 high revs - Al Civic
thanks for the information.

the revs are constant. about 2000 then drop to 1000.

Al
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Thu 2 Dec 2004 20:40
Golf mk2 high revs - Robble
My Dad's golf does that as well. Its the automatic choke in the carburettor thats making the engine rev like that. It could just be sticky, or it could be knackered. You're probably getting lousy fuel economy too.

These auto chokes are horrible. Fitting the weber carb could be better.

Rob

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Thu 2 Dec 2004 20:52
Golf mk2 high revs - pmh
If you search this forum you will find a lot of advice.

Failing that look at

This link is one of the best definitive guides I have found for this carb. Well worth reading for all old VW owners!

www.clubgti.com/forum/forum_posts.asp?TID=46724&PN...1





pmh (was peter)
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Fri 3 Dec 2004 10:13
Golf mk2 high revs - Al Civic
thanks for the info robbie. i am thinking of changing some of the switches red and grey this weekend. And possibly the thermostat. i think i have three switches on that coolant manifold, need to check.
i think my 3/4 valve may be staying on to long.

cheers
Al
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Fri 3 Dec 2004 12:24
Golf mk2 high revs - Peter D
Thee is braided earth strap at the rear of the carb, if this has snapped / correded( commom Prob ) the is no return for the wax stat tick over unit and the revs only drop when the engine is almost fully warm. You can find the unit by the single wire coming from it and it should be fed with 12 volts ignition on. Regards Peter
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Fri 3 Dec 2004 12:26
Golf mk2 high revs - Peter D
Further. The reason for the high revs after the motorway run is the throttle body is cooled down dramacilally with a high speed contant throttle run and the effects of the hot water auto choke are offset by the waxstat being cooled down a lot.
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Fri 3 Dec 2004 12:39
Golf mk2 high revs - Al Civic
Peter do you know what controls the 3/4 point unit? it definatly seems to stick out to often. eg it should only be out when the car is cold.

ta Al
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Wed 8 Dec 2004 15:42
Golf mk2 high revs - Drew20
quite a lot of misinformation on this thread so far!!
;-)
the problem is your TTV (thermo time valve) which is a black circular thingumy just above the 3/4 point unit with two wires and two vac pipes.
the purpose of this jobbie is to prevent any vac getting to the 3/4 point unit for the first 1-6 seconds after starting. This is temp dependent.
my guess is that the electric supply to the unit has gone meaning that the temp of the unit is controlled by the ambinet heat under the bonnet rather than the built in heater.
quite easy to replace
let me know if you need one as I probs have a few lying around

btw the 3/4 unit should stick fully out when off and for the first few seconds of running, then it will pull back a bit (as the TTV kicks in)
when you turn the engine off, the plunger should fully withdraw (for a short while) under the control of the overrun solenoid
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Fri 10 Dec 2004 10:04
Golf mk2 high revs - Al Civic
Hi Drew
This sounds quite like the problem, I have. Ill try and get one.

cheers
Al
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Thu 30 Dec 2004 18:59
Golf mk2 high revs - Al Civic
Hi Drew, the description of the problem you have given, seems to match the fault perfectly. I have had a look about but cant get a TTV. Where abouts in the UK are you? I may take you up on one of your TTVs.

Ta Al
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Thu 9 Dec 2004 01:45
Golf mk2 high revs - madux
check the Waxstat - it gets really bad when the revs never drop below 2000rpm
Replacement is about £30 - but you can delay this by unbolting it and refitting it upside down (honest!)
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Sat 11 Dec 2004 14:41
Golf mk2 high revs - GGH
Make sure the water feed to and from the waxstat does get hot, the water flow to the waxstat on my 1.6CL stopped flowing at around 130,000 miles. I could force mains water pressure around the waxstat circuit but I never cured it. I have be told that there is a (rubber?) O ring in the head gasket that over time swells up and stops the flow and the only way to rectify the problem is to remove the head. I did not have the time to remove the head, so I stopped the waxstat working by adjusting it's cam so it did not work at all. The wife's 1.6CL which is one year older but has only covered 85,000 miles still works as it should.
Regards GGH
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Thu 16 Dec 2004 18:32
Golf mk2 high revs - rubjonny
The coolant feed to the waxstat & autochoke is a common fault causing over reving until the engine gets really hot. The rubber o'ring is NOT in the cylinder head gasket, and the head does NOT have to be removed to replace it.

The o'ring is located to the rear of the engine between the cylinder head and inlet manifold, to replace it you remove the inlet manifold and releated components. The bolts are tricky to get to however and a long thin socket extention bit is recomended to get to the middle bolts located between the inlet and exhaust manifolds.
Once off, replace the gasket and o'ring and you'll soon have a sweet running engine ;)

This procedure and many more carb checks are listed under the URL to the clubgti forums mentioned a few posts up!
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Sat 18 Dec 2004 11:43
Golf mk2 high revs - GGH
Thanks Rubjonny for the info, so that's where the pesky O ring resides. Another problem I had was a period of poor idling which was caused by the short rubber vacume pipe/hose from the inlet manifold to the first brake servo inlne valve. The pipe looked fine with the engine off, however with the engine running the pipe flattened and inspection showed it had a split running down it's entire lenght allowing air to be drawn into the inlet manifold.Understandably brake performance was affected was well.
Regards
Gerald
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Fri 31 Dec 2004 10:05
Golf mk2 high revs - Al Civic
Hi Drew, the description of the problem you have given, seems to match the fault perfectly. I have had a look about but cant get a TTV. Where abouts in the UK are you? I may take you up on one of your TTVs.

Ta Al
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Fri 31 Dec 2004 17:16
Golf mk2 high revs - Negger
I'm having similar problems with a 1600 Mk2 '88 with 188K miles!, including poor running & excessive fuel consumption.
Having removed two water pipes to the wax-stat, and then two to the auto-choke, I expected to loose coolant, I didn't!! I could force water out of the pipes by squeezing heater matrix tubes. Would this be a good indication of knackered 'O' ring ?, or perhaps simply air-locking? Any comments please before I replace the o ring and manifold gasket!?
Many Thanks
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Sun 2 Jan 2005 12:32
Golf mk2 high revs - rubjonny
I would say so yes! Only suggestions I can give you is to make sure you can get to all of the bolts before you start, you need a long & thin extension bit to get to the last 2 bolts. Theres a bit more info in my FAQ post here:
www.clubgti.com/forum/forum_posts.asp?TID=46724
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Thu 14 Feb 2019 16:43
Golf mk2 high revs - Spudfozzy

Hey guys,

I know this thread is 15 years old so I probably won't get a reply haha.

Did you end up fixing this issue? Mine is currently doing it so was hoping for a solution.

Cheers!

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Sat 16 Feb 2019 10:57
Golf mk2 high revs - Big John

Depends on the engine and model but if fitted with the pierburg 2E2 this was noted for auto choke issues - which I think was the issue further up the thread. The autochoke uses a "waxstat" to adjust the chokeflaps and idle and I think there was a diaphragm somewhere in the gubbins (it's been a whie since I've been near a carb!) - the problem you will have is carb parts are rare now and many mechanics that knew how to rebuild/fettle carbs have retired! You can't plug a computer in to diagnose these!

Edited by Big John on 16/02/2019 at 11:25

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