84 gti K Jet

Hi Evildust thanks for the reply after all I have checked . have you any suggestions on how i correct this Thanks Regards Dave W

First of all i am suggesting to check spark plugs. By colour chart you can decide in which side you must go next. Are all 4 spark same colour? Maybe yust one cylinder failing.

Thanks for that evildust.What would be the outcome of having number 1 and 2 cylinders having 150 psi and 3 and 4 having 120 psi .Would this make a difference to the running.

the wear limit If there's difference of more than 42 psi, between any cylinders. If the reading for two adjacent cylinders are around  21-41 psi. lower than the readings for the other two cylinders your cylinder head gasket is probably blown. 

150 psi is healthy, 120 psi is getting low, worn valves seats or build up of carbon deposits?

I would think about taking the head off and having a look, but up to you as head work is a few £££..

Thanks Mark How do I check compression ratios properly . I have been taking  number 1 out and putting the tester on ,starting the engine , taking the reading, then number 2 and so on . I really do not know if this is correct or notThanks for your help. Regards Dave W.

I remove all the spark plugs and rotor arm from the dissy.

screw compression tester into No.1 and crank the engine on the starter motor till the gauge does not go any higher, (usually takes about 30 secs of cranking) take the reading then move onto No.2 etc.

make sure your battery is in good condition and fully charged.

Don't pump the accelerator etc while cranking the engine over as you don't want fuel vapor floating about.

This is how I've done mine before but there may be other ways??

I ran my engine for about 5 years with low compression on a couple of cylinders, and it still kept going till I could find the time/money to get it sorted.

mark1gls said

I remove all the spark plugs and rotor arm from the dissy.

screw compression tester into No.1 and crank the engine on the starter motor till the gauge does not go any higher, (usually takes about 30 secs of cranking) take the reading then move onto No.2 etc.

make sure your battery is in good condition and fully charged.

Don't pump the accelerator etc while cranking the engine over as you don't want fuel vapor floating about.

This is how I've done mine before but there may be other ways??

I ran my engine for about 5 years with low compression on a couple of cylinders, and it still kept going till I could find the time/money to get it sorted.

You can also take out fuel pump relay, to dissable fuel pumps.

and also if some of cylinders is lower than the others, perform wet compression test, to identify more detailed where is problem. 

Thanks again mark and evildust I will try and check again . All I did was disconected the HT lead and turned the engine over, I only cranked it for about three seconds.....obviously not long enough .Thanks again ,regards Dave W.

Hi Mark did exactly as you said .The four cylinders read 180 psi ,so do you think the heads ok------Thanks for your input .Regards Dave W

Yes thats a good pressure on the cylinders so head gasket and piston rings etc all seem good and healthy.  

Thanks Mark It seemed to run a bit better today ,maybe its clearing itself ,its still misfiring but not  popping back into the air intake.also what,s the best way to check the timing as I can,t get the timing light over the timing hole.Cheers Dave W.

Mark, while I.m at it ,do you know how to check the w.u.r I have taken an old one apart and put power to it, I could not see the metalic strip moving , but it was getting warm, is there any thing else you can do to find out if it,s working or not. Thanks in advance. Dave W.

Sorry, I've not had to work on a WUR so don't know how to test them etc, maybe some info in the Haynes manual on testing them?

Neither can I, but I can google.

http://b2resource.com/PDFs/wurfix.pdf

https://www.ebay.com/itm/Rebuild-kit-to-fit-Bosch-Warm-Up-Regulator-WUR-MERCEDES-PORSCHE-VOLKSWAGEN-VW-/272712635916

You can check it with pressure gauge. 

Thanks everyone for the info. I did google it but it seems a bit highbrow for me to attempt that.Also I have no way of getting any pressure testing equipment I will just carry on hoping my problem does not lie with the wur.Thanks again regards Dave W.

Just looking at a post on :fuel systems and exhausts; about changing injectors I had air shroud in mine and I changed to non air shroud Should I have changed the inserts as well Regards Dave W.HI  Mark I see your online , What do you think about the inserts…..Regards Dave W

Hi bud have a look at my previous message about the WUR, page 1… once i resolved this i had the car tuned as it was running rich. Prior to this i took out the Fuel pressure Regulator on the FD, new shim & rubber on that to keep a good pressure on the fuel system into the Meter head - pressure plate, along with the WUR stuff…