poor running 91 8v

[Slimmedmk2]

hello,just wondering if anyone has any suggestions.My 91 1.8 8v is running really badly at the moment.Most of the time i try to start it and it fires then dies and takes ages to fire up again and when it does it runs on 3 cylinders and then clears.It also,when driving along and i put my foot down hard it splutters and doesnt want to go anywhere.It is overfueling i think because it kicks out black smoke if i really boot it.I have changed plugs leads rotor arm and dizzy cap but it has made no difference

[gti69]

It might be the timing??

[Slimmedmk2]

would that cause it to overfuel though?

[Slimmedmk2]

not really, just the things i described

[Slimmedmk2]

apart from the revs stick sometimes at idle and when i come to junctios etc,but i had put that down to the isv

[mk1]

Check the condition of the connections to the air mass sensor and the ECU. Have seen corroded terminals give the same fault. Good luck, Steve.