1,8i acceleration dies at full throttle

[blackslizer]

Hi, I have been running 220k km now on my 99 1,8 M43TUB19 (1.9 L (1895 cc/115 in³)
NO Aftermarket parts for the engine as far as i know
ok now for the problematics:
Worst on coldstart(summer temps atm)
Cant flatend the throttle for fast acceleration(looses power)
kind of "dies" staggering when givin full throtle real fast
maxes at about 4k rpm (if throttle is applyed slowly while clutching it can pass4k5 to rev limit(throttle release at that moment makes the power drop to almost none acceleration.

this is what i have done so far. changed O2 sensor (lambdasonde) the first visual one from the exhaust manifold.

Diagnostics said it was something like 1st cylinder line o2sensor faulty

and something about Karburator wich the mecanich didnt say much about. Anyhow i dont know alot about this stufs.

i also noticed an secound "sensor thing" futher back on the exhaust could it possibly be that one that is faulty?

What im going to do:
Change oil
New sparkplugs

Thanks alot and keep up the good work on this site

[darkhorse737]

Cant flatend the throttle for fast acceleration(looses power)
kind of "dies" staggering when givin full throtle real fast
maxes at about 4k rpm (if throttle is applyed slowly while clutching it can pass4k5 to rev limit(throttle release at that moment makes the power drop to almost none acceleration.

<<< do you know that your car is fitted with a rev limiter? thts so ur engine is protected from engine overspeed...

[darkhorse737]

changed O2 sensor (lambdasonde) the first visual one from the exhaust manifold.

<<< the pre-CAT 02 sensors hardly ever go bad. In most cases, when you do get 02 sensor failure and u can't pinpoint whch one is bad; take a chance on the after-CAT 02 sensors instead.