ALFAGTV6.COM

Lucio wrote:

sira wrote:TS AFM have Bosch code number 0 280 202 202 and 5 pins but my V6 AFM have code 0 280 202 180 and 7 pins???

Bosch AFM for Euro GTV6 (+ 75's and 90's) is:
0 280 202 013
Bosch code for USA cars (including Milano's) is 0 280 202 010.

Dunno where your 202 180 comes from. Certainly it is NOT the original AFM (perhaps a better one?)

Lucio

ups wrong typing, 202 108 Bosch made in France

sira wrote: ups wrong typing, 202 108 Bosch made in France

This is the original AFM installed on cat-equipped Milano 3.0

Lucio

Lucio,

Be very friggin' careful about swapping incorrect AFMs. You can fry your internals in a "NY minute" as they say here. I've seen a LOT of motors go to 'Motor Heaven' as a result of A/F mismanagement. They are definitely set up & matched to the ECUs they correspond to.

The 7 vs. 5 pin is probably the fuel pump actuator contact. (?)

I'd attack the usual suspects to pinpoint this problem. Electrical contacts, clean all sensors including the O2, TPS, AAV, etc and I bet you'll correct your issue.

UPDATE!

brookstroutr wrote:Lucio,
Be very friggin' careful about swapping incorrect AFMs. You can fry your internals in a "NY minute" as they say here. I've seen a LOT of motors go to 'Motor Heaven' as a result of A/F mismanagement. They are definitely set up & matched to the ECUs they correspond to.
I'd attack the usual suspects to pinpoint this problem. Electrical contacts, clean all sensors including the O2, TPS, AAV, etc and I bet you'll correct your issue.

Installed the 010 AFM and even another L-Jetronic. The problem is still there.
It seems the engine isn't getting fuel at the right pressure, though the fuel pump seems OK (or so it was before installing the new AFM).
Next week it will be inspected again (injectors etc.). I also have starting problems now, in the sense that the starter doesn't turn quickly. It is very slow, like it was feeded by an old battery (fresh battery didn't solve the problem). I'm starting to think everything is caused by an electrical problem: starter, AFM, ECU and fuel pump might not be getting correct voltage).

Lucio

Earth/ground strap from engine to body??

Barry wrote:Earth/ground strap from engine to body??

Nice idea! I'll pass it up to my Alfa mech.

Grazie
Lucio

Lucio,

What are the problem symptoms your car is having exactly? It sounds like the NTC (temperature sensor) may be faulty. This is the one that tells the ECU what the coolant temp is; not to be confused with the temperature guage sender. This can easily ne checked with an ohm meter. Read it cold and then set the sensor in some hot water and re-read it; about 71 degrees C. It should show a difference.

brookstroutr wrote:Lucio,

What are the problem symptoms your car is having exactly? It sounds like the NTC (temperature sensor) may be faulty. This is the one that tells the ECU what the coolant temp is; not to be confused with the temperature guage sender. This can easily ne checked with an ohm meter. Read it cold and then set the sensor in some hot water and re-read it; about 71 degrees C. It should show a difference.

Symptoms:
The engine is very erratic and irregular. Genarally it has no acceleration to speak of. To avoid irregularities one has to accelerate very slowly and avoid revving above 3000 rpm. It seems it doesn't get enough fuel (or air?)

Now it has even developed a strange behaviour while starting: it seems the starter motor turns very slowly (or it doesn't turn at all). A new battery hasn't cured the problem.
Finally, when I activate a turning light (right or left) the speedometer goes up and down wildly, following the turning light on/off sequence. Yeah I know it seems voodoo

A new AFM and ECU didn't cure the problem. I'm clueless


Next Monday I'll pay my Alfa mech another visit.

Lucio

Lucio,

The mechanical problem appears to be a fuel or spark problem; i.e. fuel starvation or lack of spark advance. I'd check the timing, cap & rotor and the plug wires. How do the spark plug tips look? They'll give you an indication of how the motor's A/F mixture. Your starter sounds like an electrical connection somewhere. Look at everything.

1. The Thermo-Time switch can be checked - that's the sensor in the middle of the 3 on the t-stat housing. BTW, the single wired sensor is to be disconnected per Alfa Romeo. The switch ohm resistance readings are: cold - 0; hot 100 - 160 ohms. No repair. Replace if faulty.

2. The AAV can be checked for opening & closing operation by seeing if it is open when cold & open when hot. You can remove the AAV from the cylinder head I clean with electrical cleaner which works pretty well.

3. The Trottle Position Switch (TPS) on the trottle body has a quick test. Manually move the throttle; engine off, slowly from idle position. If you hear a 'click', that means it's reporting off idle mode. The TPS registers 3 positions; a. idle, b. normal running and c. wide open throttle (WOT). OHM testing is checking the center terminal with one of the others to get 0 on one side and infinity on the other at closed throttle & just the opposite on WOT.

The turn signal issue is again electrical; grounding I'd bet. These cars are prone and you think a vodoo is in there; my Maserati Biturbo's got a Mojo...

Try these tests for process of elimenation.

Later Brooks

Hey, is your battery cable in good shape...check it out under the car...mine was grounding intermittently as it passes through the frame and causing similar problems.....

I am definitely on the "check the big grounds" band wagon. Using a turn signal might well provide an alternate ground path that allows everything to run correctly. Try a voltage drop test at the battery ground and the big cable from the radiator crossmember to the engine. If voltage drop test doesn't sound familiar just make a good ground in parallel at each point with a battery cable. You know to take that ground apart and clean it up if performance normalizes.