after new gasket and decoke/comp tests etc tickover lumpy

[dorame]

Hello Guys
VW Golf mk3 1.9 driver
After diagnosing for a lumpy tickover my local garage changed my head
gasket grinded the valves and refitted everything, on friday he rang me to
tell me that he is having problems with no 4 cylinder and its and the
engine was not running right .
(No 4 cylinder was one of the 2 Cylinders that had the wrong pressure
reading in the initial test) and after the refitting all the pressures are now
ok. but the plug is clean, he says that injection (single flow I think )is ok
and also he has used a camera to check which found no problems .
I am taking it that he has tried the obvious things like ensuring the plug is ok electrics etc. he is the garage owner and chief machanic and he has taken the over from one of his other mechanics. he has also done any work that was needed on the same car with no problems.
maybe something that you guys have had trouble with, and solved,
anyone have any thoughts?
TIA

[towcestervag]

i know its pretty obvious but get him to check the servo hose to the inlet manifold as thse split
also if its a driver it a 1.6 or 1.8 not a 1.9

[dorame]

i know its pretty obvious but get him to check the servo hose to the inlet manifold as thse split
also if its a driver it a 1.6 or 1.8 not a 1.9

towcestervag
My mistake 1781cc it is, just bin down the garage this morning no problem with the hose.
He has the block on the bench again, he showed me the plug which was clean and all the others were ok, as I said before single point injector which supplies all the cylinders at the same time, he has had camera evidence valves closing and opening ok, skimmed head, 12bar compression ok.
He says that he will borrow another injector although he can find no fault with the existing one.
I can see why its doing his head in.

[Trog_nfs]

has he reset basic settings on the throttle body adaption?

[dorame]

has he reset basic settings on the throttle body adaption?


That's a new one to me Trog, so I did a lot of googling, and I think that should definitely be looked into, the one thing I'm puzzled about is
if that is the cause wouldn't it not cause problems in all of the cylinders and not just have a clean plug in no4?
I will ring him in the morning, am I right in saying by what I have googled that this (basic setting) have to be done with a computer? And if the flap has carbon deposits, will a bit of carb cleaner squirt and a few cotton do a fix? (My total lack of knowing anything about cars might be showing here)
Bring back the old Morris minor I say.

thanks

[Trog_nfs]

i couldn't say for sure how the effect may manifest, the only reason it came to mind is it is often a bone of contention for many golf owners.

edit: just had a thought. Has he checked to see if the inlet manifold is cracked on the 4th cylinder side?

[towcestervag]

monojet systems dont work like that
if the injector was faulty it would affect all cylinders not just no 4
i would check the servo hose again as this goes to no 4
also check the monojet unit base gasket as these split but does affect all cylinders
also on the inlet manifold check this as there is a seal between no3 +4 cylinder
if it only no4 cylinder check for air leak on that cylinder
has he put diag machine on car ??

[dorame]

i couldn't say for sure how the effect may manifest, the only reason it came to mind is it is often a bone of contention for many golf owners.

edit: just had a thought. Has he checked to see if the inlet manifold is cracked on the 4th cylinder side?

no cracks detected,
had a thought, if that injector has got electronic control, and if he removed the battery before he did the gasket job, would any settings data then be lost?

[dorame]

i know its pretty obvious but get him to check the servo hose to the inlet manifold as thse split
also if its a driver it a 1.6 or 1.8 not a 1.9
Spot on towcest and thank you, that was the problem apparently, he said that he did check that after suggested he try that on tuesday but it was only after this same issue was highlighted (apparently just a pinhole in the hose can be a problem) by the garage technical advice company that suggested he have a second look with a smoke gun (which he didn't have).
I took along a printed page highlighting the above.
So I have got my motor back again but for how long? it going back into the hospital next week, I noticed soon after that the pitch of the revs was higher than I have ever heard it on this car (it remained constant for the 10 years I've had it but I was assured by the mechanic that it couldn't be adjusted and because I've had a fresh decoke etc, this was now the normal tickover pitch, I'm not sure I buy that. can anyone say on that model car about what rev counter's reading on tickover? I am accustomed to a lower tickover (I do not know what it was as I have taken it for granted and I can find no reference in the handbook.
During my general driving after I left garage today I noticed that in stationary traffic if my foot touched the gas pedal increasing the revs slightly, it sometimes did not decrease on removing my foot (and the pedal does not appear to be sticking.)
The oddest problem was after I got home I started the car again two hours later and the revs gradually increase on its own up to about 220 on the counter
very strange
excuse me rambling on

[SammoVWT]

220 or 2200?

if the revs are idling higher, it could well be because the throttle body / battery has been disconnected, or maybe even the maf (if it has one?)

may need basic settings done on via a computer etc#

I dont know about other golfs, but the mk3's are very particular in having things reset to work properly

[towcestervag]

monojet units dont need reset
if its idling too high its been adjusted wrong!

[dorame]

monojet units dont need reset
if its idling too high its been adjusted wrong!

please forgive my novice question, is a monojet unit another name for a single point injector? (never heard of either before all of this) and could you explain where are the point/points of adjustments?
I have noted at about the point where the cable connects to the device it curls around a half circle where it ends, is that the point of adjustments?

[towcestervag]

monojet is single point injection
looks like a carburettor but is a injector
there is a idle screw at the end of the cable which should not be adjusted
there are no adjustments on the monojet unit they should be factory set

[dorame]

I had my motor back today,problem now sorted to satisfaction.
mechanic told me that the un stable revs was caused by a collapsed vacuum tube.
True or not, it now sounds and feel like my car. so I am happy.
Thanks for all the helpful contribution from the great guys on here, cars are a lot more complicated than the austin 7s we used to have on the road in the 40s for sure.

[towcestervag]

glad its sorted mate good luck

[Housemaster300]

Im having a very similar problem on exactly the same engine(1.8 abs) im going to check the hoses once again today.
From the intensive research i have done it seems that you cant do a throttle adaptation on theses ecu's.
Another hilighted problem is the 4 pin coolant temp sender on the top hose pipe at the front of the engine.
Also the IAT (intake air temp)sender.
Im gunna replace the vac hoses today.

[Crasher]

Check the servo feed pipe rubber elbow as towcesterVAG said earlier.

[Housemaster300]

Ive already replaced that mate :(,i checked he no return valve this morning and it looks like it is passing a tiny bit towards the servo,is it worth changing that crasher?

[Crasher]

They should allow air to flow from the servo, not the other way.

[Housemaster300]

The one way valve flows the correct way(towards the inlet manifold) but if i blow on the pipe the other way it passes a little,would it be worth replacing?
If so is it called a brake vacum pipe non return valve to the ilset manifold or a much simpler name?ha ha

[Crasher]

It is a complete new pipe.

[Housemaster300]

Great stuff thanks.

[dorame]

glad its sorted mate good luck

Just when I thought twould be safe to get in my car and drive any distance, problems rears its ugly head again.
I had noticed when the car was returned to me the water in the flask was a bit low and clear which I just topped thinking it was nothing more than a bit of carelessness , today checked it again and noted block wet and water has again dropped below the recommended level, so they probably havent tightened the block enough or tightened out of sequence.
I have got a new job to do tomorrow about 20 miles m11, I wonder if its safe to drive that distance, dilemma if I dont start I will louse the job.