MK1 Golf GTi - 1.8 DX Engine - Cold Start Problem

Yeh guys, works so much better now. I'm now going to replace timing belt and then will check timing etc with a strobe.
I believe the rpm at operating temp is 900 to 1000 as per the Haynes Manual. Can you please confirm this is correct?
Thanks

yeah 900 to 1000rpm is right the lower the better really but may struggle a bit at 9
to stop the hesitation from cold I took the wur apart again maybe 5th time now
but I adjusted the regulator body out a fraction and put it all together and bam sorted
hot cold and warm starting revving sweet as
glad where all sorted now    

I'm sure WUR should stand for something else
What Utter Rectum maybe

Hi all,

The cold start issue haunts me again. But this time it appears to be pointing at the cold start valve (CSV) and thermo time switch (TTS). When cranking cold, I'm not getting any +ve power to the CSV connector. My test lamp is working ok.

Before I fork out money to replace the TTS, is there anyway to test it and the wiring harness.

Are there any relays or fuses connected to the CSV system.

Thanks

Just an update. Followed the Haynes manual, connected the CSV connector with a test lamp and removed distributor center HT lead and earthed it, cranked the engine, no power.

Second test, removed connector from TTS and connected test lamp from earth to green / white wire terminal, cranked and there is light from test lamp.

Then I tested it from CSV green / white terminal and I get a light.

Now the confusing bit, doing a continuity test between the CSV and TTS terminals, no continuity between both green / white to green / white and red / black to red / black. However continuity from red / black to green / white and red / black to green / white.

This is driving me mental. What is going on.

Found a very good write up via the link below on how the TTS functions and how to test and fault find.


https://www.sl113.org/wiki/Engine/ThermoTimeSwitch

Will follow this to determine the issue and advise findings.

Sorry forgot to ask, is there a relay to operate the cold start valve?

Hi all,

Cold start injector is working. I fit a new one and tested the harness, all good.

Finally my car is on the road after 18 years.

I still have lumpy running with the car.

When started cold, it idles above 1000rpm. When I tap the accelerator it lowers to 850rpm.

As it warms up it is very lump, even when driving.

When it reaches operating temperature it idles ok but seems a little rough.

I replaced the complete air box with metering unit with a second hand one which made things worse, the exhaust was letting out white smoke so I put the original back on.

Yesterday I tanked it up with super unleaded and put in redex in it. This K Jet system can be a knightmare.

I am thinking of the following possibilities,

- clogging in fuel system (put redex yesterday)
- ignition issue (heard the resistance varies from cold to hot to provide a good spark)

Timing is good and as per manufacturer specifications.

Any suggestions or ideas is much appreciated.

Finally the car is sorted after spending £££. I sent the WUR and Metering Head to KMI Injection. The units came back like new. Fit a new set of injectors and set the CO as per the Haynes manual, now the car is running sweet.

Sent from my ASUS_Z00AD using Tapatalk

BRINZ said

Finally the car is sorted after spending £££. I sent the WUR and Metering Head to KMI Injection. The units came back like new. Fit a new set of injectors and set the CO as per the Haynes manual, now the car is running sweet.

Sent from my ASUS_Z00AD using Tapatalk

out of interest, what did KMI charge?

I have recently had the exact same issue you initially described on my GTI Cabrio.

Dismantled the WUR and found that the larger aperture fuel way/gauze was blocked (not visibly), so it wasn't allowing fuel system pressure to drop at cold start, even with the diaphragm open.

Had to use the air gun with a narrow nozzle at about 5 bar to free it up, rebuilt with new seals etc, good as new!