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sf49er

I recently picked up a two owner, rust-free 1990 33 1.7 IE with cat and only 36k miles on the meter. I was driven regularly for the first few years but from around 1995 to about 2005 only got less than a thousand miles a year. At the time it rested in a heated garage when not driven.

It last passed the Swedish MOT inspection in August 2006 without any notes. Since around mid-2007 it has been in cold storage in a barn, regularly started every other month or so and allowed to be warmed up. However, since I first looked at it a year and half ago it has not been started.

Now to the problem -- it runs on two cylinders only! It has new NGK sparks and the problem seems to be the injection on the rear two cylinders. Can't remember the cylinder numbering but guessing it's 3 & 4. Have replaced one injector which had incorrect resistance.

However, it appears there is a constant 0.5 V across the connector on the injection. It means that with the connectors attached the fuel is constantly pumped into the cylinders. I have now disconnected them and thus have an 850 cc two cylinder engine.

Studying the wiring chart and workshop manual for the Motronic has made me no wiser so I'm now turning the experts on the system I know hangs out here Wink

A couple of questions;

1. I used a regular digital multi-meter to measure the voltage across the connectors and in DC mode I get a reading of app 0,5 V. The reading doesn't flicker and the voltage is there as soon as the ignition is turned on. Would a meter of this kind show flickering if the voltage were periodic to open the injector?

2. In which way would the injectors for the two rear, opposing cylinders be connected and/or related?

3. Since it has been sitting for a while in a sometimes damp, unheated barn I thought it might be oxidation on some contacts somewhere but appplication of 5-56 on the injector contacts and the multi-point connector on the control unit on top of the air flow meter hasn't had any effect. It also seems odd that the two feeds should show the same symptoms. Any suggestion for connections to check without having to backtrack the entire circuit?

4. I assume, that since the injectors for the foremost cylinders work, it is not related to lamda probe or any of the other sensors. They may be the target of work once the injection works on all four cylinders in order to get the emissions within bounds. Would this be a correct assumption?

I spent the weekend with the car at the grand opening of a new local Alfa dealership. At hand was also the GM of the previous importer who is now managing the spares logistics. He has a past as manager for service for the Swedish sales organization as well as team manager for his sons STCC (Swedish Touring Car Championship) effort and we discussed the problem. He had no suggestions and was just as perplexed as I am!

As you can tell, I'm at a loss and look forward to any helpful suggestions!
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

johnboy · Posted: Mon Sep 13, 2010 6:50 pm Post subject:

Hi
are you getting anyu sparks from the two rear sparks plugs,the leads may have broken down?

regards john
_________________
WODA WE NEED? MORE POWER!!

Alfa gt jtdm blackline
1990 S2 16v veloce sleeping!
2002 ts gtv the wifes now
1997 seadoo gsx 800
1999 freestyle superjet

sf49er · Posted: Mon Sep 13, 2010 7:54 pm Post subject:

Yup! Sparks from all four plugs. Used both an external spark plug tester as well as unscrewed the sparks and checked!

Since posting I have now replaced the ECU (the control box on the firewall) with one known to be working. At the same time disconnected, used contact spray and reconnected a number of connectors. They all looked fine with no sign of corrosion or other unpleasantness.

No change whatsoever, unfortunately!
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

paulhide · Posted: Mon Sep 13, 2010 8:32 pm Post subject:

I assume you have compression in the rear cylinders.
Check all earths, especially the L-shaped point by the starter motor. Strange things happen when earthing points are not clean, as I have just found out recently.
Fit another ECU-injectors wiring loom.
_________________
Owner's Club 33 Registrar. Now from P4 & S2 1.7 QV
http://www.alfa-pages.co.uk/viewtopic.php?t=5188

sf49er · Posted: Tue Sep 14, 2010 2:14 pm Post subject:

Problem solved Laughing

Had nothing to do with the fuel supply whatsoever! Someone in the Swedish club suggested checking the resistance of the spark plug wires as well as making sure the wires were connected correctly. That's where I found the problem. Someone had switched the #3 & 4 cylinder wires into the distributor cap Sad

I assumed, since the car had been sitting idle, that the caretaker hadn't done any tinkering with it. Obviously that wasn't the case. So instead of checking some obvious problems I dove straight into trying to solve more complicated problems. Lesson learned would be -- never assume anything and start troubleshooting the simple stuff first!

Now it runs like a charm and everything is wonderful! Next up are the rear brakes (drums) which seems to have suffered from being in storage. Right rear drags and the left rear has no brakes which I assume could be a sticking wheel cylinder. May need replacing but after solving the engine problems it seems like a piece of cake to attack.

Thanks for the advice and now that I've found the forum I'm sure I'll be back!
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

johnboy · Posted: Tue Sep 14, 2010 3:18 pm Post subject:

Cool good news
So I was close as I said check the spark plugs and leads Laughing

Brake should just need greasing to get them moving

John
_________________
WODA WE NEED? MORE POWER!!

Alfa gt jtdm blackline
1990 S2 16v veloce sleeping!
2002 ts gtv the wifes now
1997 seadoo gsx 800
1999 freestyle superjet

sf49er · Posted: Tue Sep 14, 2010 8:55 pm Post subject:

Yes, you were right while I was barking up the wrong tree!

I also assume the brakes just need getting everything moving freely and greasing them!

A load of other pics in the same directory - http://www.tvc.se/AR/files/33/small
_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

Oggie · Posted: Wed Sep 15, 2010 8:06 pm Post subject:

Just a point regarding your rear brakes, if the left rear wheel won't bleed it will be the rear brake compensator which sits above the right side of the rear axle, it has 4 brake lines feeding into it and a bar from the rear axle to activate the brake on cornering therefore stopping the least unloaded wheel from locking up. It can be a pain to fit unless you have a ramp!. Rolling Eyes

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PHAT 33

Admin

sf49er · Posted: Thu Oct 07, 2010 1:10 pm Post subject:

Just a follow-up to report that the 33 has now passed the Swedish MOT-equivalent with flying colors and quite a few appreciative remarks from the inspector. Actually it drew a small crowd of personnel to see a 20 year old Italian car without any trace of rust -- quite unique in Sweden with it's rough winters and loads of salt on the roads. Next inspection no later than end of February 2012 Smile

All the brakes needed was a clean-up and loosening the stuck cylinders and handbrake mechanism. Now a perfect left/right brake distribution!

And of course it has the Jetronic system! My mistake and confused by the 155 which does have the Motronic designation. Smile

_________________
Bo M. Hasselblad
Linkoping, Sweden
Secretary of Club Alfa Romeo Svezia
sekreterare@alfaromeo.org

johnboy · Posted: Thu Oct 07, 2010 1:21 pm Post subject:

Well done chap enjoy it now Cool

_________________
WODA WE NEED? MORE POWER!!

Alfa gt jtdm blackline
1990 S2 16v veloce sleeping!
2002 ts gtv the wifes now
1997 seadoo gsx 800
1999 freestyle superjet