Mk1 gti is slooooow

Hi Chaps,

I've owned my mk1 gti for about 8 years.

I only drive it a few times a year, and to be fair to the old girl it always starts up after 6 months of no use, a few splutters then idles and runs lovely BUT it just seems slow to me!

I've had a few mk1s and mk2s over the years, and for some reason this one just lacks the oomph the others have, floor it and it makes the rights sounds, but just doesn;t seem to shift like I think it should?!

Any suggestions on what may be making it low on power?

It doesn't knock, smoke, overheat and it idles perfectly . . . . . 

fuel flow limiting, as in Fuel is old, filter is clogged…

You may want to check the insides of the tank (WARNING you need 3/4 to 1/2 of a tank to inspect).

Timing, Vacuum leaks
(Specially if you have a Vacuum Advance on the distributor.)

Off the top of my head, and the type of fuel system you have Carbed, Injected (cis) or (Digifant) would help.

Briano1234 said

fuel flow limiting, as in Fuel is old, filter is clogged…

You may want to check the insides of the tank (WARNING you need 3/4 to 1/2 of a tank to inspect).

Timing, Vacuum leaks
(Specially if you have a Vacuum Advance on the distributor.)

Off the top of my head, and the type of fuel system you have Carbed, Injected (cis) or (Digifant) would help.

If fuel filer was clogged or dodgy pump then surely it wouldn't run as well as it does though?

Same with the timing?

Its a 1.8 gti DX engine code and it has vacuum advance on the dizzy.

When was it last given a good service, spark plugs, HT leads, dissy cap, rotor arm etc…

What fuel are you using, normal or super unleaded?

What do the braided rubber hose connectors look like for the vacuum advance on the timing side of things?

Is your car a tintop with the smaller fuel tank and without the lift fuel pump in the tank?

mark1gls said

When was it last given a good service, spark plugs, HT leads, dissy cap, rotor arm etc…

What fuel are you using, normal or super unleaded?

What do the braided rubber hose connectors look like for the vacuum advance on the timing side of things?

Is your car a tintop with the smaller fuel tank and without the lift fuel pump in the tank?

Hi mark,

Thanks for the reply.

Its a 1983 tin top gti.

I dont think I've ever changed the dizzy cap etc. but its only done about 3000 miles in 8 years . . .if things like this were dodgy I wouldve thought it was more  likely id have misfiring etc?

Its run on normal unleaded.

The timing as has already been suggested is the obvious one, I would check the ignition first, it's easy to mistake the TDC for the 6deg mark and they still run reasonably well.
If that's okay have a look at the valve timing.

I always used Super Unleaded in mine.  Try it !  The Timing could have been Retarded for it to run on ordinary Unleaded.

i had similar with a 1.6 and turned out it had a deisel gearbox fitted at some point. might be worth checking the code, also with that few miles done i would check the tank for varnish, then test injectors