George, try replacing the coil in your GTV-6. Thomas Gonnella
-----Original Message----- From: alfa-digest <[email protected]> To: alfa-digest <[email protected]> Sent: Thu, Feb 10, 2011 5:22 pm Subject: alfa-digest V10 #2407 lfa-digest Thursday, February 10 2011 Volume 10 : Number 2407 Forum for Discussion of Alfa Romeos, etc. Richard Welty <[email protected]> Digest Coordinator Contents: [alfa] Marginally High CO Emission from L-Jet Spider [alfa] administrivia: Powell's Books [alfa] Re: Marginally High CO Emission from L-Jet Spider Re:[alfa] GTV-6 has a miss [alfa] Milano brake pads Re: [alfa] Re: Marginally High CO Emission from L-Jet Spider Alfa Digest Home Page: http://www.digest.net/alfa/ Send submissions to [email protected] Send administrative requests to [email protected] To unsubscribe, include the word unsubscribe by itself in the body of he message, unless you are sending the request from a different address han the one that appears on the list. Include the word help in a essage to alfa-digest-request to get a list of other majordomo ommands. ---------------------------------------------------------------------- Date: Wed, 09 Feb 2011 14:02:19 -0800 rom: Robert Lorenzini <[email protected]> ubject: [alfa] Marginally High CO Emission from L-Jet Spider On 02/09/2011 01:31 PM, alfa-digest wrote: Marginally High CO Emission from L-Jet Spider The temp sensor also affects rich/lean. Raising the resistance = richer. Bob ------------------------------ Date: Thu, 10 Feb 2011 07:30:02 +0000 rom: Richard Welty <[email protected]> ubject: [alfa] administrivia: Powell's Books Other ways to support the digest Richard's Amazon wishlist: ttp://www.amazon.com/wishlist/30PQXKZQN9GWX/ref=cm_wl_rlist_go there is more than one list on amazon, see the menu on the left). Powell's Books affiliate: rusty Motorsports (parent of digest.net) is affiliated with owell's Books, a highly regarded bookstore in the Pacific Northwest. se this link to access Powells and buy books, and it'll help: http://www.powells.com/cgi-bin/partner?partner_id=25667 ------------------------------ Date: Thu, 10 Feb 2011 04:46:00 -0500 rom: [email protected] ubject: [alfa] Re: Marginally High CO Emission from L-Jet Spider Charlie Slayman wrote: > But I don't want to spend more money on testing until I've exhausted the simple causes. Since HC and NOx levels are good and O2 is at 0%, things point to a rich mixture rather than a bad cat. Since water temp sensor is working and O2 sensor appears to be working, I'm leaning towards leaky injectors. But before I pull them and send them off for cleaning and rebuild, I'm going to try tightening the AFM spring and take it in for a second test. I'm so close to passing that I want to minimize my work. Thanks, Charlie F you wanted, you could pull the fuel rail and injectors free of the nlet ports and activate the fuel pump, then check directly whether the njectors are leaky when closed. Just a thought. Our LJet Spider was unable to cope with the lean (over-strong spring) FM setting with which came to us. The functional O2 meter showed us a ero signal (tens of mVolts) until we spiked its intake manifold with ydrocarbons, upon which it started telling us more than zero, and upon hich the engine smoothed out and started running more happily. I know -some- springs lose spring constant over the years, having heard too any stories of suspension springs sagging. It seems worth tightening up he AFM flapper spring before doing more invasive things. How will you tell when you have hit upon the Right Thing among the many ou are planning? If you can't get a sufficiently fast voltmeter, you ight want to borrow an oscilloscope from someone. Gosh, the way things re going in the electronic world, you might be able to get an LCD eadout 'scope with kHz resolution for $69.99 pretty soon. Michael ------------------------------ Date: Thu, 10 Feb 2011 05:01:13 -0500 rom: [email protected] ubject: Re:[alfa] GTV-6 has a miss George opined thusly: Date: Tue, 8 Feb 2011 23:22:25 -0800 From: George Graves <[email protected]> Subject: [alfa] GTV-6 has a miss My GTV-6 has developed a miss. It runs fine at steady throttle at anything below about 4000 rpm. But if the car is asked to pull an incline, even a slight one it's starts to miss randomly -but not badly; just noticeably. Also it will miss more consistently if you take the revs above 4500 under hard throttle. I don't see any loose hoses or any such thing and it has essentially new Bosch +4 plugs. Any suggestions? George Graves '86 GTV-6 3.0 'S' nder load a few things happen. One is that cylinder pressures go up. his makes the spark plug harder to drive to breakdown, and as others ave said, can reveal ignition components which are then weaker than the lug gap. I had a 164 dist. cap get dirty enough inside to fail from rcing, although when the engine and cap were cold they'd work if you ept the RPM up and the manifold pressure low. Lug it down and let the ylinder pressures rise, or let it get warm and increase the onductivity of the dirt, and it would not run. I've also seen problems t the coil tap give your symptoms, and because the coil supplies all parks, the failure would wander around the various cylinders very rregularly. Your problem sounds to me like this, although a failing lug wire or a cracked or tracked distributor cap could do it, too. Or a otor irregularity could also be the culprit. I'd suggest carefully leaning the coil tap (which fixed one of my examples above), and ossibly swapping out the dist. cap/rotor and finally the plug wires. You can create higher cylinder pressures by running on fewer cylinders. ou wouldn't want to burn your cat, but if you were to pull a few njector wires, you might be able to create high enough cylinder ressures in garage conditions to reveal weaknesses in the ignition omponents. I haven't tried this....it just occurs to me that it should e possible as a diagnostic test. It wouldn't run raw fuel through the at like pulling plug wires alone would do. Michael ------------------------------ Date: Thu, 10 Feb 2011 20:20:57 +0000 rom: [email protected] ubject: [alfa] Milano brake pads I just found a stash of Textar brake pads that fit the front of the Milano. OEM ompound, no sensors, made in Great Britain. Please let me know if anyone is nterested. Gary ------------------------------ Date: Thu, 10 Feb 2011 14:20:10 -0800 rom: Charles Slayman <[email protected]> ubject: Re: [alfa] Re: Marginally High CO Emission from L-Jet Spider Michael, I like your idea of pulling the injector rail and looking for leaks with the ystem energized! That fits my criteria of simple/inexpensive tests. Thanks, harlie On Thu, Feb 10, 2011 at 1:46 AM, <[email protected]> wrote: > Charlie Slayman wrote: But I don't want to spend more money on testing until I've exhausted > the simple causes. Since HC and NOx levels are good and O2 is at 0%, > things > point to a rich mixture rather than a bad cat. Since water temp sensor is > working and O2 sensor appears to be working, I'm leaning towards leaky > injectors. But before I pull them and send them off for cleaning and > rebuild, I'm going to try tightening the AFM spring and take it in for a > second test. I'm so close to passing that I want to minimize my work. > > Thanks, > Charlie > IF you wanted, you could pull the fuel rail and injectors free of the inlet ports and activate the fuel pump, then check directly whether the injectors are leaky when closed. Just a thought. Our LJet Spider was unable to cope with the lean (over-strong spring) AFM setting with which came to us. The functional O2 meter showed us a zero signal (tens of mVolts) until we spiked its intake manifold with hydrocarbons, upon which it started telling us more than zero, and upon which the engine smoothed out and started running more happily. I know -some- springs lose spring constant over the years, having heard too many stories of suspension springs sagging. It seems worth tightening up the AFM flapper spring before doing more invasive things. How will you tell when you have hit upon the Right Thing among the many you are planning? If you can't get a sufficiently fast voltmeter, you might want to borrow an oscilloscope from someone. Gosh, the way things are going in the electronic world, you might be able to get an LCD readout 'scope with kHz resolution for $69.99 pretty soon. Michael ------------------------------ End of alfa-digest V10 #2407 *************************** -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
