I am not sure what the exact problem is but here are the symptoms
Cold Start: Starts fine, idle sounds good, bit jumpy until it warms up. Temp gauge often does not move as I only drive 5 min to work.
Warm Start (e.g. 5 min after cold start above): Starts fine, idle sounds good, temp gauge rises rapidly, and will reach 3/4 on gauge. Cooling fan may or may on come on. When stopped idle remains (quite) fast. Engine temp rises in compartment. All coolant hoses and inflow manifold appear to get uniformly very hot.
Sometimes after the temp has risen I am gettign overrun when I turn off the iginition, but this is not consistent. I am not using the car for long journeys at the moment as I am not confident the temp will behave.
I think the fast idle is causing the excessive temperature which is causing the over run
Fuel economy is rubbish (<20 mpg) and used to be quite good 30+ mpg
I have purchased a new cooling fan switch.
I have checked the air intake vacuum is working
I have cleaned the carburettor with carb cleaner
I have replaced air filter
All vacuum lines I have examined seem intact
From what I have read it is an 2E3 Pierpoint carb, and any of the following could be the problem
Waxstat
Thermo numatic time valve
Throttle position control diaphragm
Choke pull-down diaphragm
But I am not sure how to begin to eliminate what is going wrong
Any help/ideas appreciated
Thanks
Peter
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Peter
Can't make any sense of that lot - you may have multiple problems.
The fast idle is probably the Waxstat on the carb. [That's not going to cause o/heating.]
The rapid temp rise suggests a water pump, or thermostat, fault. [The running-on is a side-effect of that.]
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Thanks Screwloose,
I suspect the Waxstat based on my reading of similar problems on forums like this one.
Why would you suggest the water pump ? What are the symptoms of a water pump failing ?
I was not counting that as the coolant pipes, input manifold and radiator are all getting pretty much equally hot?
Would the cooling fan failing be enough to result in the temp behaviour ?
Which thermostat are you referring to ?
Thanks again
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I was wondering about the circulation because of your mention of rapid temp increase when idling.
The thermostat control the water flow to the radiator.
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Cheers Screwloose
Taking your suggestion of a possible water pump problem ..........
I had another look into this from a cold start today. I started up and let it run for about 5-10 minutes, and monitored where heat was building up by touch. Heat build up started at water pump which became too hot to touch. Inlet manifold had a heat gradient hotter near block and only warm at the back. Top hose to radiator got warm, but bottom hose remained cold.
Radiator was cold to touch. Coolant pipe running to pump across back of block got hot. Some of other pipes became warm, Heater was not on.
Temp gauge was about half at this point
I then stopped the engine for a couple of minutes then restarted. Temp gauge rose rapidly to almost 3/4 on gauge. Top hose to radiator got a bit hotter than before, but bottom hose got only slightly warm. Radiator again cold to touch. Inlet manifold again had a gradient, but was hotter than previous near block. Other hoses warm.
Does this sound like a pump not pumping and coolant "circulating" based on temperature difference alone ? In particular the temperature differences through out the cooling system ?
As heat is getting to the radiator (even if slowly if not pumped) I am guessing the thermostat is OK.
Reading Haynes, as the system is pressurised, should you be able to compress the hoses (any of them) with gentle pressure when engine is running or should they be rigid ?
A slightly different question, why would the coolant level in the pressure vessel rise and stay up even after I removed some of it between journeys?
Thanks again
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That doesn't sound like proper circulation; without the fan on, the rad should be hot all over.
Water pump impellers fail for fun on these and it's a very typical scenario.
Hoses should be squeezable - but firm. Water levels can be affected by localized steam pockets.
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Latest update
Have had the coolant flushed, and a new water pump and thermostat fitted and car is running better, fuel economy is doubled at least. But there are still some problems
First I took it for a 50 mile trip after I got it back, temp went towards 3/4 at very start of trip then back to 1/2 and stayed stable there. Car ran great.
Then on a couple of small trips (3-5 miles)the following has been happening
Temp rises to 3/4 and stays there. Engine revs increase and stay high as if the choke was stuck full on
At the end of one with temp at 3/4 and engine revs up the top radiator hose was hot the bottom one almost cold
What could be causing this ? Where do I start to look next ?
Any ideas appreciated ?
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Some additional info
Intermittent fast/racing idle is now the problem
Short trip yesterday (3 miles approx 5 min) 2 miles on moterway, car behaved perfectly on motorway and revs dropped as expected as I exited. Temp approx 1/2
As I then drove approx 1 mile home, temp rose to 3/4 and revs as well and neither settled back. Touching the accelerator did not help.
Cooling Fan was coming on/off
Sounded like choke was full open
Car is 1990 MK2 1.3 Golf with Pierburg 2E3 carb
Could this be caused by Thermo switch/Temperature Sender ? Is this linked to auto choke ?
Any help appreciated !
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those carbs are a pain to fix up once they play up
no amount of internet tips or haynes reading could fix mine...i bit the bullet and bought a used weber from ebay , runs like a top now and its so simple to tune and ajust
there was a guy on ebay offering a refurb service for pooburg carbs dunno if he still operates?
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After recently having water pump and thermostat replaced, previous problem of run on is cured.
Intermittent fast/racing idle is now the problem, associated with temp at 3/4
Short trip yesterday (3 miles approx 5 min) 2 miles on moterway, car behaved perfectly on motorway and revs dropped as expected as I exited. Temp approx 1/2
As I then drove approx 1 mile home, temp rose to 3/4 and revs as well and neither settled back. Cooling Fan came on/off as expected
Sounded like choke was full open, but I have no rev counter to be exact.
Car is 1990 MK2 1.3 Golf with Pierburg 2E3 carb
Could this be caused by Thermo switch/Temperature Sender ? Is this linked to auto choke ?
Any help appreciated !
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Above problem solved (finally and hopefully definitively)
Cause partial blockage of the hose from spherical expansion/pressure tank to engine, which was moving along hose.
Problem was indicated by the RISING level of coolant in the spherical, which did not subside, even after running with cap off in case there was an airlock. But temperature would appear fine at times, then not at others.
Other symptoms which have gone away, include, shudder over first couple of miles, slight crackle/backfire sound from exhaust.
Car is going very smooth from the start now. mpg back avg 30 odd
Temperature is steady about 1/2 mark.
Lesson learned.
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I have very similar problems with my golf. Running on, intermittent high revving on idle.
I am thinking of looking at the water pump and thermostat first.
When you changed the waterpump, was there obvious signs of a problem? Did you make any changes or repairs tot he carb?
Your feedback would be greatly appreciated.
Peter
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Hi
Had local mechanic change pump for me
Fixed temp issue
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I have the original problem back again, car fine when cold, once warmed up (to half on gauge at which point it is stable) the revs come up and stay up. Fuel economy is rubbish again. Also discoved oil in air filter compartment (from crank case ? How does this happen ?)
Car is 1300 MK2 Golf Poerburg 2E3 carb (which does not have a waxstat)
Any thoughts appreciated
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