Hi guys, I renewed the spark plugs, rotor arm and distributor cap then the leads in that order. After renewing the rotor arm and cap it didn't seem to miss when it was idling, but then the next day it was back to its usual self.
After that I changed the leads. With the new leads it solved the fact that it was missing when I was driving. So now when I put my foot down there's good power and it sounds lovely. Unfortunately its the same situation when I pull up. Once it is idling it seems to be missing on one cylinder.
The thing that baffles me is why after changing the rotor arm and distributor cap it seems to run fine while idling for a while, only for 1 day though.
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What color is the offending plug? If you remove it after it has been idling, oily?
Could be it is oiling up at tickover (or just oiling up, and then wont spark at tickover)? Rings or Valve seals?
That could account for why after new plug it is ok on tickover. Just a long shot but poss worth looking at.
or
Does it have nasty full depth sparking plug covers with rubber and metal screens? On old cars there is no substitute for wire cables and old push on connectors when looking for problems.
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pmh (was peter)
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If it does not miss at higher revs then it is unlikely to be compression causing the problem at tickover.For £20 you can buy a compression tester from Gunson if you want to be sure.
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Well I'm getting the compression test tomorrow for 20 quid. Pmh, excuse my ignorance, but I don't know what "sparking plug covers with rubber and metal screens" are. You're not talking about the leads there are you??
No, I don't think there is oil getting into the combustion chamber. On the old plugs there was no oil. The only thing was carbon build up so it seemed that it was running a bit rich. That's why I originally suspected a carb issue.
I am hoping at this point that maybe there is an issue with one of the leads or plugs that is stopping it firing. The only thing is when I put my foot down it doesn't seem to be missing at all and that's in line with what someone told me regarding the cylinders. Once you accelerate the compression builds up and then it stops missing.
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Make sure you get a comprehensive test for your money.
You should be told;
1) compression pressures on 4 cylinders
2) ditto after a squirt of thick oil into each cylinder
1) will tell you of general state of compresion, and pinpoint any variation between cylinders
2) will tell you whether any poor compressions are the result of bore wear, or valves, because the oil will temporarily seal the bores.
Are the valve clearances OK, and not too tight?
Does it make any difference swapping around plugs or leads - ie is it always the same cylinder?
Is the cooling water OK - no slow leak into one cylinder?
Air leak in one branch of the inlet manifold?
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I'm with Cliff here if the compressions are ok I would be searching round the inlet manifold gasket for a leak with my stethoscope or a length of windsreen washer pipe. I would also be checking around the flexi isolation gasket that joints the carb to the manifold although that would effect all cylinders. Regards Peter
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You should also check the brake servo vacuum hose where it connects to the inlet manifold. This hose commonly rots and splits on the old VW's.
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Its at this point I wish I had a good memory, my friend had a VW Jetta 1.3 that had this exact same issue. I cant remember the name of the part but there is a little plastic bit that costs £6 to replace and will cure this fault.
I know thats not much help but it may give you the faith to try and find it.
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I think the consensus so far is that there are still lots of very simple things to check, before jumping to the conclusion that the engine is worn out.
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OK, first of all thanks for all the replies guys. I got the compression test done and this is what the guy jotted down.
Cylinder 1 190Psi
Cylinder 2 165Psi
Cylinder 3 185Psi
Cylinder 4 120Psi
However, when he replaced all the leads after he had finished it seemed to be ticking over quite nicely, which leads me to believe I hadn't put one of the leads on properly when I changed them (Yes, I feel stupid) this is why it was running OK a few weeks back in between the time I changed the Distributor cap and leads.
My question now is whether 120Psi on cylinder number 4 is within acceptable limits?
I suppose my next step is to get an emissions test done. It definately was running a bit rich judging from the old plugs and I'm not sure if this 120Psi thing on cylinder number 4 might lead to it failing an emissions test. Anyway I'm just relieved that it is not missing on one cylinder when idling like it was before.
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Did he repeat the compression test after squirting a small amount of oil down each plug hole to see if the values went up?
If the values were higher after doing this, it would suggest that the valves were sealing ok in their valve seats and any leaks were caused by worn piston rings.
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I think the usual definition of acceptability is within about 15 psi between cylinders. So yours is not perfect.
However, it runs well, and you say that even the uneven idling seems to have been cured. I would leave well alone now, and just use the car, but bearing in mind that maybe it might become a problem at a later date.
Low compression could just be a sticking piston ring.
I would:
1) sort out the wiring, plugs, distributor etc and make sure that is all tip top.
2)Check all low tension wiring, contacts, connectors, earthing points.
3)Run some carb cleaner through the tank
4) Make sure the inlet system is good - no leaks, clean out air intake, new air filter, clean engine breathing pipework, vacuum connections, etc
5) Give it a good run, and then change the oil and filter
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'3)Run some carb cleaner through the tank'
Far better to use cleaner that is sprayed directly into the carb with the engine running,cleans loads of gum and muck off and can improve running no end.
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'3)Run some carb cleaner through the tank' Far better to use cleaner that is sprayed directly into the carb with the engine running,cleans loads of gum and muck off and can improve running no end.
That's true, and a good point. I was thinking of getting some cleaner actually inside the carburettor - jets, passageways, floats etc, in case something was a bit sticky there.
Also I've just remembered the old trick of running the engine in pitch darkness, and looking for arcing round the HT system.
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I looked at my Haynes manual which gave compression pressures at cranking speeds for the VW Polo, which has the same engine in (just different ignition and induction I think). If my math?s is right, when I convert your psi readings into bar, I get:
Cylinder 1: 13.1 bar
Cylinder 2: 11.4 bar
Cylinder 3: 12.8 bar
Cylinder 4: 8.3 bar
It said the compressions when new could be anything between 10-15 bar, and the wear limit is 7 bar, which means that three of your cylinders are good, while the fourth one is acceptable. However, they say the maximum pressure difference between cylinders should be no more than 3 bar.
I would take Cliffs advice, and as long as the car seems ok, just use it.
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Thanks for the tips guys and that info, Roberson. I've got the MOT booked for tomorrow morning so I've got my fingers crossed. I was going to get an emissions test prior to the MOT, but I have to get the tax renenewed in a few days as well. It's still running much better than it was anyway so hopefully it will pass.
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Ha, it passed the emissions. Even the guy who tested it couldn't believe it. Unfotunately it failed on about 5 other points. Mostly minor apart from a cracked CV Gaitor. Does anyone know how much that costs to put right and if it's a big job??
I'll have to declare it sorn for a while anyway, cos I'm skint.
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Cv boots are dirt cheap at GSF but can you do the necessary?
what miles has this done, my lad had one that did mega miles, give it a thrash(100mph) to clear the crap out. body wise they are worth sticking with, otherwise you are into Fords and body rot
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>>give it a thrash(100mph)>>
We talking about a 1.3 Golf here...:-)
I used to have a 1989 Jetta with the 1.3 engine and four-speed box - if I got it up to 80mph or a bit more on the M6 I was quite chuffed.
By the way the two Jettas I used to own featured sparking plugs with not one but three electrodes - never could find out what the gaps were supposed to be.
- - - - - - - - - - - - - - - - - - - - -
What\'s for you won\'t pass you by
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Mostly minor apart from a cracked CV Gaitor. Does anyone know how much that costs to put right and if it's a big job??
If you do not want to do the dismantling try a split boot.They cosy a few quid more(£8-10 typically)but mean you can do the job in 10 mins.V.important not to get oil or grease on it though.
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If you do not want to do the dismantling try a split boot.
IMHO, only use if you want to get it through this years MOT and are not intending keeping the car for another year. Chances are a split boot won't last until next MOT time.
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At most I'm thinking I might keep this car for 2 years so may need to do another MOT. Is any dismantling required at all for this split boot kit??
Where would I find an idiots guide? I'm trying to make sense of the driveshaft diagram in my haynes manual.
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No, you don't need to dismantle anything to fit them. I have seen them advertised in Car Mechanics magazine, I think from a company called Eurocarparts.
My next door neighbour has used them.
Basically the old boot is cut off with a Stanley knife, the grease in the joint is replenished and the new boot is wrapped around the joint and glued together. From what I remember the grease and glue are supplied in the kit together with full fitting instructions.
His experience was that the kit worked ok. It is very important to ensure that the area which is glued is completely free of grease, oil etc and is scrupulously clean. It also pays to hold the joint together well until the glue sets.(only a couple of minutes)
HTH
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www.honestjohn.co.uk/forum/post/index.htm?v=e&t=14...4
Use the search and you will find a variety of comments
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pmh (was peter)
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Hi PMH, I did do a search, but didn't find any specific instructions on how it is fitted.
Anyway, I just rang Volkspares and they told me that split gaitors will not pass an MOT. I also seen a similar comment elsewhere on the web. Does this vary from place to place?? I would much rather get the split gaitor in time for the free retest, but now I'm not sure.
Have you guys passed an MOT with one of these split gaitors??
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I did have to fit a pair on a Escort-though this was about 6 years ago,it did pass the MOT but not certain how long they lasted for.But as long as the joint is sealed I see no reason for a fail
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Steve
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I would much rather get the split gaitor ....
Get a stretch gaitor instead. It's mentioned in the link above by pmh.
IMHO split gaitors are given that because shortly after fitting them they'll split again.
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Does anyone know somewhere in NW London where they sell the Stretch gaitors?
I'm going to ring Halfords tomorrow, but my local motor shops don't seem to stock them, neither do Euro car parts or GSF in NW London :(
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Absolute rubbish,I've used loads on cars that have gone through an MOT.There would not be much of a market for them if they would not pass an MOT,ask these people why a split gaiter should fail.Done properly they are fine,those who say they are carp usually haven't the patience to take care and keep the job scrupulously clean.
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Totally agree! Most of the garage trade dont understand the words " patience to take care and keep the job scrupulously clean".
I have used sucessfully them in the past.
I think the problem here is in the use (or understanding) of words! Will a split gaiter pass the MoT?
Answer1. No if the gaiter has a split in it. (ie damaged)
Answer 2 Yes if the gaiter is of a split seam design and is designed to clip together and be permanently glued on the seam.
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pmh (was peter)
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Well, I've gone and bought a Stretch gaitor now anyway. The person who was meant to fit it for me probably won't be able to, which means I will miss my free re test tomorrow.
Unless I could remove the hub and fit it myself with only the jack to hold the car up. Problem is I'm a bit thick, as you may have gathered. Is it easy to take the hub off?
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Usually the drive shaft is retained in the hub with a large nut done up really tight. The size is usually bigger than the normal 1/2 inch drive socket set. The torque needed to undo and re-tighten the nut can be enough to break the 1/2 inch ratchet/tommy bar kit as well.
I would advise most strongly against doing this with just a jack. If the car falls off it, you may get crushed but the car won't feel a thing. Axle stands are a minimum requirement.
As well as removing the nut, some suspension joints will have to be released to allow the hub to be pulled off the driveshaft, and the driveshaft held in the gearbox whilst this is done. If the driveshaft pulls out of the gearbox you will have gearbox oil everywhere.
Some force has to be exerted to flex the hub off the shaft. In doing this it is all too easy to dislodge the jack.
Some care also needs to be taken to avoid damaging any brake/steering/suspension componants as well.
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Thanks MJM, I should have bought the split one. I'm such an idiot :(
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Try contacting www.bailcast.com They do mail order, may have a local stockist, if undamaged you may be able to return the one you have.
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I'm bringing back the stretch one and swapping it for a split one tomorrow morning.
Any idea how long the glue takes to set on the split ones?? I have to get the split one at 9am and then have the car there for the free re test at 12:30pm at the latest. I hope it doesn't get messy, mixing grease with glue etc.
Any tips on applying more grease and fitting it without messing it up would be appreciated.
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Sorry, this is a bit late!
By now you should have the kit with full instructions. From memory, it is a "superglue" type almost instant glue. There should be some grease in the kit.
Let us know how you get on!
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I despair. I got the kit from a small motor spares shop, not in it's right box and with no instructions. It is supposedly universal, yet when me and my dad looked at different ways of cutting it down to size there was no way it would have been wide enough at it's widest point to stretch around the driveshaft where the old one came off, hence the glue could never have been applied to keep seal it.
We were going to cut it and use the supplied clips to keep it on, but that have been unlikely to pass the MOT and would have cost more to get it done properly afterwards. Therefore I missed the re test and will probably just buy a normal gaitor and pay a local garage to fit it.
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Sorry it didn't go as planned.
A local garage should have all the equipment and know-how to fit it. It shouldn't take long so hopefully the labour bill won't be too big.
I would have thought that an hour of their time should sort it.
Someone with more experience will no doubt correct me if I am a mile out.
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