S3 33 1.7 IE running 'issues' - Alfa Romeo Forum
You are currently unregistered, register for more features.    
Thread Tools Search this Thread
(Post Link) post #1 of 3 Old 08-04-15 Thread Starter
Status: -
HalfManHalfDog's Avatar
Join Date: Mar 2009
Location: France
County: Poitou Charente
Posts: 1

Member car:

1992 33 1.7 IE

S3 33 1.7 IE running 'issues'

After several boxerless years I recently bought a 1992 33 1.7 IE (no cat) and apart from age related niggles, I'm having trouble with a 'juddering' in gear between 1000-2000 revs when I apply gentle or no throttle pressure.
My previous Alfas had carbs so this newfangled injection stuff is a bit beyond my expertise.
It 'feels' as though the fuel cut off is kicking in before the throttle is fully closed, there's absolutely no hesitation if I push the pedal down a little further.

The only adjustment screw readily accessible (and mentioned in french 'haynes' equivalent manual) is the CO2 screw in the airflow meter box.

There's also a small problem of the engine stalling/dying at stops, but this is happens most often on downward slopes. Perhaps this might help with diagnosis?

Cold idle is about 1500, dropping to 900/1000 when warmed up.

Despite these problems it's a great little car, though I'm still a bit shocked by the complete lack of rust
HalfManHalfDog is offline  
Sponsored Links
Status: -
AO Silver Member
edward's Avatar
Join Date: Dec 2003
Location: United Kingdom
County: Somerset
Posts: 3,000

Member car:

156GTA & 33racer

welcome to the forum.
edward is offline  
Status: -
AO Silver Member
LoneWolf33's Avatar
Join Date: Jun 2010
Location: Hungary
County: Budapest
Posts: 1,376
Images: 52

In case of Jetronic injection equipped 33s the system is very sensitive to vacuum leaks
between the vane air-flow meter and the intake ports.

The following things may need to be checked:
- Condition of high tension parts of the ignition system including rotor arm,
distributor cap [centre carbon brush length and the wear four segments],
spark plug leads [in a dark place you may see small sparks through the insulation
[when the engine is running], and the spark plugs.
All four spark plug electrodes should be light brown(ish).

Differences between the spark plug electrode colors may result of uneven compression.

- Basic ignition advance timing at idle RPM, with engine at operation temperature.
Checking with a timing light/strobe gun the advance should be stable, no jumps
allowed. (jumps in the timing advance may suggests failed ignition advance control unit)

- Air filter, fuel filter, correct operation of fuel pressure regulator.

- Throttle position switch and it's correct angular alignment.

- After many years of service the air-flow meter could be faulty as well. It may sends
incorrect values to the injection controller unit, mostly in the low RPM range.

I hope this may helps.
LoneWolf33 is offline  

Go Back   Alfa Romeo Forum > Supported Alfa Romeo Models > Technical & Vehicle Assistance > Alfa 33, Sud & Sprint

issues , running

Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

For the best viewing experience please update your browser to Google Chrome