Help me - 1990 16V Problems

Hi Guys

Bought a 1990 16v Oak green Five door a couple of weeks ago. Guy had owned it for 14 years! Thought it would be a good buy as fairly tidy.

Drove it home and it was gutless!
I have sinced changed the dist cap/leads/rotor arm and plugs and noticed it wasn't getting full throttle so put in a new acc cable. The result is the car runs a lot better but still not quite right. Still not as quick and smooth as it should be.
I changed the thermostat as I noticed it was running cold, and changed the powersteering belt whilst i was there. The coolant header tank was all gunky and looked like some oil content was in there, so put a new one in so I can monitor it better, the old one you could'nt even see through. I don't think it has head gasket issue's so not sure whether oily residue naturally builds up over years or whether there is another way it is getting into the water.
right, so you would think all would be well now, the car only has 125,000 miles on it.
However it is still not right and to top it off it has an exhaust blow, can a blow slow performance on these? It has a magnex manifold and dtm exhaust system. Not my cup of tea and it is ridiculously loud!! It only blows when under load so I cannot work out the problem on the ramp, sounds like it is the manifold blowing, however there is a funny gasket where the exhaust meets the manfold, can this blow under load only? car sounds like a tractor. I want to ditch the Magnex system and go back to standard mani/downpipe and a Jetex exhaust system. Where can I get standard components from at a cheap cost? Am I right in saying I would need to get a manifold/downpipe and then the Jetex will make up the rest? This would be much quieter and stop the neighbours moaning ?

Sorry for the essay, just at my wits end, as I have owned the car for two weeks and not even had a good pleasurable drive!

Do I need to check the timing, is this done on the cambelt? or do people mean electronically? what does a rolling road setup constist of? do i need to do this?

Please help!!

Justin

 

The donut gasket where the 4 branch meets the system at the compensator can fail so that would be my first area to look at. Easy enough to remove it & check...

If not then the manifold itself may be leaking[:^(]

For a decent quiet system, just get a 3 box jetex & mate it to the back of the 4 branch.

TSR should be able to advise on getting a Jetex compensator to join the 2 parts

 

Cheers

I think I may ditch the manifold if the donut doesn't work.
Do you think the blow could be effecting performance?

Thanks

Justin

 

The 16v cars are pretty sensitive to ignition timing, and cam timing. If the ignition timing is retarded, you'll lose a lot of power, and probably have a lumpy tickover with a 'bap-bap-bap' exhaust sound, rather than a smooth burble.

If the car still has it's original cam chain, that'll make a big difference too, if it's stretched. If you take the cam cover off, you should have no more than a couple of mm of play in the chain. If there's any rattling from the right hand end of the cam cover, that's probably a loose chain, but they lose power before they start getting noisy.

It may well be a good car, but just in need of a tune up. Don't start worrying just yet.

An exhaust leak will hurt the performance too, but not a massive amount.

 

Gunky coolant could also be down to mixtures of anti-freeze over the years. Hard to tell without actually seeing the gunge in question. RJ^^ is usually right though Sorry, I mean ALWAYS right!

 

Thanks

is it a case of just finding a second hand exhaust mani and down pipe, can't find them anywhere.

I have heard bad things about the Magnex Manifold cracking etc. Plus I think this is why the exhaust is so loud? It is a three box system but it is unbearable.

PS - is it a case of checking timing marks on rotor arm/cambelt/cams/fly? rocker off?
PPS - if it turns out to be head gasket failure, would you do the gasket and do piston rings at the same time or move onto an engine upgrade?

Cheers

I have a million other things need sorting:
Has a gear box leak, looks like someone has tried to bodge it with paste on the main seal.
Has a Cobra alarm, the drivers lock comes up, but all the rest try and come up and then go back down again, likely to be the pump or air lines?
(5 door) rear door window seals don't fit well, like they have shrunk, are these still available.

I will get some pics up of the car and a bit of a restoration build thread going
I have come from Audi TT's and MK4 golfs to this MK2 golf, so slow learning curve. I know 1.8T's inside out, but NA older engines are alien to me.

 

Wherever your exhaust or manifold is leaking, you should see black soot, and be able to feel a draught. Be careful, because the manifold warms up very quickly. If the manifold is leaking, you should be able to hear which end of the car the noise is coming from. Get it up on axle stands and stick your head under there. Manifold leaks will be very loud at the front end of the car.

All 4 branch manifolds can break especially if the engine mounts are tired, causing the engine to move around.

To diagnose the central locking, I'd try blocking off the pipes one at a time, to narrow down where the leak is. You have to lift the carpets to get at some of the pipes. It could be the pump is failing too.

It's probably better if you split these issues up, and have a look, or post in the relevant technical sections.

Where are you based, and how handy are you with a set of spanners?

 

Hi

Probably best I do split them up as i ramble
I am in Bedford - I work for a VAG specialist called the TT shop, but none of the techs there have much knowledge on the older cars as we don't go older than MK4 golfs normally.
I have the resource but not the knowledge, I am happy to get on the spanners myself as the techs always want a cash handshake for doing stuff. (i work in sales but can get my fingers and thumbs on the spanners) my trouble is this is a daily driver at the mo.

I have had the car on the ramp to find the leak, it doesn't blow on tickover or revving which is annoying. Only under load, I can find no obvious black. So being on the ramp has not helped. When going along it is a tractor.

PS you guys are ultra helpfull.