Alfa Romeo Owners Club of Australia Forum

Technical => 160 Series (90, 75, 164 Sedans) => Topic started by: Alfa75V6 on April 19, 2009, 12:19:39 PM

Title: Alfa 90 issues
Post by: Alfa75V6 on April 19, 2009, 12:19:39 PM
Wondering if anyone has had these issues with their 90.




First off, just replaced the plugs with a fresh set of DENSO, the car has 116000KM, and the plugs might be original, and there isn't much left of the Golden Lodge,..........

The problem is the car (which by the way, I just bought it 2 months ago, so do not know a whole lot about it) revs itself.....yes, once i start it, it just keeps revving high and low between 800 and 1700 RPM, over and over again, eventually it settles on 1100-1200 RPM, but every 20-30 seconds, it will shoot up to about 1700-1800 RPMs on it's own.........plus major hesitation when I accelerate, every time I try to give it gas, it seems like it will shut off, and then it revs up.....

I have a new set of 8mm Magnacore spark plug wires, just waiting on a new distributor cap and rotor to come in next week, and see if that solves anything........

Any ideas?
Title: Re: Alfa 90 issues
Post by: dehne on April 19, 2009, 02:03:47 PM
 check cold start injector, timing might be out a little, when its warm how does it idle
Title: Re: Alfa 90 issues
Post by: Sheldon McIntosh on April 19, 2009, 03:52:27 PM
2.0 litre 4 or 6?; injection or carbs?
Title: Re: Alfa 90 issues
Post by: Alfa75V6 on April 19, 2009, 04:31:56 PM
wow, just when you think you covered it all, sorry about that, it is the 90 Super 2.0 V6, injection

The engine does get smoother when it warms up, but the whole time driving it, when you give it a little gas, the car seems to stumble, it is very annoying taking off in first gear after having come to a stop....


I am assuming the the distributor car and rotor on this car is the same as the 75 3.0 V6? Being that this car was a custom import, any part that isn't equivalent to the 75s has to be imported.

Cold start injector??? Sorry, what is that? Any pictures of it? Worst part is a factory repair manual came with it......but it is in German............acthung!
Title: Re: Alfa 90 issues
Post by: Colin Byrne on April 19, 2009, 07:21:21 PM
I'm no expert on 90's but "hunting" at idle sounds more like and air/fuel issue rather than ignition, I'd be checking air flow meter  or any air leaks in the induction system
Title: Re: Alfa 90 issues
Post by: Sheldon McIntosh on April 19, 2009, 09:44:48 PM
Can you post a pic of the engine at all, I've never seen the 2.0 V6.  But I believe it has a different injection system and brand from the 2.5?

Check this link, may or may not be useful to you.  http://www.hiperformancestore.com/Ljetronic.htm (http://www.hiperformancestore.com/Ljetronic.htm)   This deals with air leaks (and other issues concerning fuel injection)  on the 2.5 V6.  Is essential reading, if not for the 90 then certainly the 75.

Hold on to the manual, even if it is in German, I've never seen a 90 manual before.  There is a fair bit of the manual you can access on the net though, try this..   http://www.users.on.net/~craigf/ (http://www.users.on.net/~craigf/)   A little bit for the 90, but most of the mechanicals are the same as the 75.  Good luck with that 2 litre though.......
Title: Re: Alfa 90 issues
Post by: Alfa75V6 on April 20, 2009, 04:11:29 AM
I never really looked into the injection system, it does look a bit different form the 75's, however, it is a Bosch setup, I think the 4 cylinder systems differ.

I will try to get you pics of the engine compartment
Title: Re: Alfa 90 issues
Post by: Alfa75V6 on April 20, 2009, 07:19:39 AM
This is under the hood
Title: Re: Alfa 90 issues
Post by: alanm on April 20, 2009, 08:51:02 AM
Hi

I had exactly the same problem that you describe – high/low revving at idle when cold. Bit embarrassing when you are sitting at the lights.
I'm pretty sure my GTV6 started doing that AFTER the air flow meter was replaced with a reconditioned unit. From memory the problem had something to do with the idle speed setting. The air flow meter was replaced because I wasn't happy with the smoothness of the idle (depending on the air/engine temp it was a little rough/erratic.

Alan
Title: Re: Alfa 90 issues
Post by: Sheldon McIntosh on April 20, 2009, 12:26:22 PM
Ah interesting.  There's a few joins there I'd be checking for tightness.  Check the 'accordion' part of the main pipe too, take it off and check inside and out - they often leak on the 2.5, probably a problem area on this too.  I've superglued all my joins so it's even harder for them to work their way loose.
Title: Re: Alfa 90 issues
Post by: Alfa75V6 on April 21, 2009, 04:33:46 PM
I'm assuming you mean the accordion piece coming out of the air filter box?
Title: Re: Alfa 90 issues
Post by: Sheldon McIntosh on April 21, 2009, 04:57:30 PM
Yep.  They often crack on the 2.5, but it looks smaller on that engine. 

Did you get this car from California?  I remember seeing one the same colour being advertised there, but that was probably a year ago.
Title: Re: Alfa 90 issues
Post by: Alfa75V6 on April 23, 2009, 05:45:52 AM
Yes, the same one from California