Back From Garage! Run out of ideas!! Please HELP!!

Hello,

I NEED HELP!!!

Basically i have a mk1 golf gti 1.8 cab on a D plate (86)

the car has a few running issues, it starts and idles ok little rough but it idles and when in netrul it revs ok.

but if ya try and drive it it drives like a old 1ltr on its last legs, no pick up if ya put ya foot down say to spped off the lights the revs drop to nearly stalling stage then pick up and you toodle off at 2mph.

i have changed spark plugs, HT leads fuel filter, timing belt, checked the airflow meter, done a compression test. every thing!!

What can i do now?? it has baffled me, my dad who has never been beaten by a car lol and a mechanic mate of mine!!

any help would be greatly accepted!! many thanks

Dan

Check ignition timing and mixture.

All checked matey!! spend whole weekend trying to fix it  

Are you setting off in 3rd gear?

paul_c said

Are you setting off in 3rd gear?

no mate… its through all the gears not just first the top speed you can do after about 10 mins is 50!! and thats not a constants speed and the engine dosent sound like it wants to!!

i only driven once for any period of tim when i picke it up i have done a few test runs after changing bits but no joy :-(

What did you set the timing to? What values did you get for CO in your mixture test? Did you check this while revving the car up, as well as idle?

set timing to the notch in gear box and the mark on the sprocket, in the compression test i got 12.1 12.0 12.1 12.6 if i remember. checked it just while revving!!

Another thing, did you check you're achieving vacuum and mechanical advance (although it won't actually make that much difference to power).

i believe so yes!!

a friend of mine seems to think it maybe a head gasket… or a manifold gasket gone??

although i rang a garage and they seem to think that it wouldnt tick over if it was an air leak?

any ideas?

If you've replaced a lot of the ignition system and checked and set the timing properly, then I'd assume its mixture, it sounds like you're lean or rich at load. Worth doing a fuel pressure test too. It could be a low flowrate from the fuel pump, replace the pump, but also this could be downstream of a blocked microfilter (just at the inlet to the pump). I notice you've already changed the main fuel filter.

It could be pressures all wrong in the fuel metering unit (metering head), or simply rust/dirt in the fuel system.

Get another garage - a car can tick over perfectly fine, with a big air leak, if the mixture is okay.

Very unlikely to be head gasket, given the compression figures you've supplied.

i think from what people have been saying and what i have checked is.. i think enough fuel is getting in and the pump sounds lke its working fine!!

gasket would be my next port of call because it does seem like too much air a bit like when ya running outta petrol, too much air not enough fuel!!

would a blowing manifold gasket gause this??

(sorry for all the q's i am new to vws and cars in general)

Robbo107 said

gasket would be my next port of call because it does seem like too much air a bit like when ya running outta petrol, too much air not enough fuel!!

Check the mixture properly!!!!!!!

silly question…

how do you check the mixture??

Robbo107 said

silly question…

how do you check the mixture??

With a gas analyser.

ahh rite…

i dont have one of those so i take it i will have to get garage to check that out!!

btt

Do prowler's injector test - free and easy

http://www.vwgolfmk1.co.uk/Main/tips1.htm

sounds very much like low fuel pressure. could well be fuel mixture too.
 if you do not have an exhaust gas analyser, try it the old fashioned way. at least it's it's free and may help solve the problem.
 there is a tube sticking up on the metering head, between the rubber egg boot thingy and the metering unit (bit the fuel lines are attached to). using a long 3mm allen key, very gently insert and turn anti clockwise to lean (i'd go this way first) and clockwise to richen. important to try not to apply downward pressure while doing this. if you go one way till it tries to stall, note that point, then go the other way until it does the same. go back 2/3 towards lean. rough but it should be a whole lot better if that is the problem. before you do this, out of curiousity, unplug the cold start injector and see if it makes any difference.
 worth taking the plugs out and seeing if they are grey/black. clean up and pop back in.
 if that works, happy days, but it does sound like fuel pressure. are you getting pops from the exhaust?