Hi!
I just bought a 92 VW Cabriolet 5spd manual it has 106k miles on it.The problem is when i push the gas pedal fast ant totally in it sound like it wants to stall for a sec.and than the rpm raises normally,but when i release the gas pedal the idle falls back too low (about 300 rpm) the car almost stalls, and after a moment it's back to 800rpm. After about 25 minutes it's running ever wors. It smokes black.It's running rich and doesn't even want to go. So this is 2 separate problems or maybe related to each other.
Compression is perfect.It has new distributor cap,rotor,cables,plugs,new water temperature sensors,new air filter.Vacuum lines checked.
The car doesn't have any check engine light!Is there a way to diagnose the the car?If there is what tool do i need to buy?I want to keep the car for a long time.Could it be oxigen sensor or injectors?
If anyone could help that would be really great!
Thank You in advance!
Peter

 

Ok I'm not a vw mech. or anything but your symtoms sound real close to the ones i was exp.in
Drove me a lil nuts after replacin plugs new O2 sensors and ign. harness.
So here ur poorman's McGyver check up.
1)When you have time and ur heading backfrom somewhere and gettocastle castle, park the car. Don't shut off. Pop your hood.
2) Go inside and get a tasty beverage for this. (car still runnin)
3) Find Your throttle body (should run right into your throttle cable)
4) Push down on the wire to see if tension is there and not loose (shouldn't be like cable tight but not loose at all)
5) Nest give ur throttle body a lil turn and rev that puppy. (ur lookin and listinininininin for any type of bad shakes or grinding sounds comin from inside that lil body that dont make the ears settle right)
6) No probs. ?????
7) Go out and pick up 2 Vw manuals at barnes and noble one McKin .....something and the others made by Bently both are bibles to have or sit and look at in one of there big fuzzy chairs.
8) I would hate to think timing belt (inside block idink, not the outside ones but do check for missin teeth or loose push down on that too)or f. injectors alreadyi would think u would be good there.
All could be symtoms and sorry if i state the obvious but hey I got all jacked up on coffeee today.
Hope this was some or any type of help.
I'll check back with ya good luck.
I'm gonna go run a 20 miles or so maybe swim across anchor bay.

 

Thank You very much for your help!

I replaced the oxygen sensor and the car runs perfect!

Peter

 

Glad it was some help, gotta love a better runnin' VW especially when it's urs.

Have fun cruisin'