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Discussion Starter #1
After Jeff Greenfield set the timing with dies the car ran very nicely for 200 miles or so. Then all of a sudden the idle went south, but the car still pulls smoothly when you give it gas (which was not the case before).

The idle is reasonably smooth at start up, but when the cold start injector shuts off it becomes lumpy. And the exhaust has a funny smell that Jeff said indicated lean running. No codes. And Jeff smoked the intake manifold, and the only leak was a small leak from the new $ 375 egr valve.

Odd that it seemed fine for a while and now it isn't. I don't think I slipped the belt, as I always park it on level ground with the parking brake on.

Car has 82 k miles. There is a leak in one flex pipe. Could that be letting in air at idle and upsetting the lambda sensor? Front coil packs have been removed and checked with no obvious evidence of arcing.

I am running out of theories.

Thanks
Rex
 

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Idling Problems

Same thing happened to my 24v. And then the former dealer (now a Ferrari dealer) here in Seattle told me I had slipped two teeth in my belt (which I disbelieved because the belt was only 4,000 miles old and still tight). I searched around for advice on this BB and "JUNGLEJUSTICE", the one who writes about reworking 24 valve engines into 3.2 liter with special injection got in contact with me. He actually came over to my garage. He showed me that there is an electrical connection (two identical -- one running three and the other running three) between power source and the individiual spark packs. We switched wires and the cylinder that previously missed ran perfectly, but a different one that previously ran fine now missed. So we went to one of my wrecks and picked out another spare, put it in, and that fixed the car. No problem since. Get in touch with "JUNGLE JUSTICE". Send him a PM and ask what the name of that electrical part is ("amplifier, I seem to recall), where it is, and discuss with him how simple it is to fix it if you have an extra good one. I may have one. And I have it still attached to the car apparatus (but out of the car), so I should run down into the garage and photo the piece (I will still do that if you need the information). But contact him. He KNOWS. Whatever you do, don't panic, and don't tear up anything just yet. Jay
 

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After Jeff Greenfield set the timing with dies the car ran very nicely for 200 miles or so. Then all of a sudden the idle went south, but the car still pulls smoothly when you give it gas (which was not the case before).

The idle is reasonably smooth at start up, but when the cold start injector shuts off it becomes lumpy. And the exhaust has a funny smell that Jeff said indicated lean running. No codes. And Jeff smoked the intake manifold, and the only leak was a small leak from the new $ 375 egr valve.

Odd that it seemed fine for a while and now it isn't. I don't think I slipped the belt, as I always park it on level ground with the parking brake on.

Car has 82 k miles. There is a leak in one flex pipe. Could that be letting in air at idle and upsetting the lambda sensor? Front coil packs have been removed and checked with no obvious evidence of arcing.

I am running out of theories.

Thanks
Rex
Did he set tension on timing belt when he set cam timing with dies as they are two seperate operations? You can do one without doing the other even though usually they are done together.

POINT OF INFO: As for cold start injector (CSI) there isn't any CSI on 164 12v or 24v motronic systems. The computer in conjunction with with coolant temp sensor in thermostat mid housing controls cold start by increasing spray pattern of all 6 injectors.

CSI are in L-jetronic system in Series 3 Spiders, GTV6 and L-Jet Milanos.

Where is small leak in new EGR valve? At idle this valve must be closed. I would be suspect of valve being open at idle and affecting mixture.

I would recheck new valve by first disconnecting hose from it and hook a vac hand pump to it and actuate it a couple times to see it opens and closes when vacuum removed. If you do it with engine idling it will probably die when valve opened or go more lumpy but should idle smooth if fully closing provided cam timing is still correct.

Exhaust flex pipe leak should not be causing O2 sensor to read false air as it should have greater pressure in pipe than atmosphere pressure.

As ignition modules (2 each) one for each bank of 3 coils, this modules are mounted to side of air cleaner box mounting bracket under round cruise control actuator area. You can switch connectors from one to the other if you like but check to be sure they are clean and then pack connector with dielectric grease.
 

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Discussion Starter #4
Thanks, guys. This at least gives me leads to pursue.

Steve: actually Jeff did not reset the belt tension, as he concluded from reading the manual that it was not required. Later he heard from others that it is, so perhaps this needs to be redone.

If so, we are putting in a new belt and maybe we'll drop in some GTA intake cams just for fun.

Rex
 

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Thanks, guys. This at least gives me leads to pursue.

Steve: actually Jeff did not reset the belt tension, as he concluded from reading the manual that it was not required. Later he heard from others that it is, so perhaps this needs to be redone.

If so, we are putting in a new belt and maybe we'll drop in some GTA intake cams just for fun.

Rex
Better take a look at cam timing again then I would be willing to bet you have jumped time on at least one cam because belt was to loose.
 

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In addition to setting cam timing with the timing dies, tensioning the belt is absolutely required.

Improper or neglected tensioning leads to incorrect timing or one of the cams (usually the rear, exhaust) jumping a tooth or two.
 

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Idling problems

Hey, you have a 24 valve with spark pack. This is a specialized problem that only a 24 valve type has. You have one of your two spark "amplifiers" gone bad. If you didn't try to do a PM to "JUNGLE JUSTICE" I guess I have to give you the straight dope. I will make it my duty to send send you a photo of the parts. You will notice that one is missing sinc I had to use it to fix the problem on my 164 LS. Teeny problem of bolt on and bolt off. I took one off the ensemble I will have to photo for you. These other fellows are suggesting that there is some slipped belt or something. Not for a minute. That's what the "specialist" told me too. He was totally wrong. I say it is merely a burned out spark "amplifier". As soon as I can take a picture I'll get it on the BB for you. Jay::)
 

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This is what I like about the BB.

Jay's advice is reflective of his experience; Other's will be different.
The problem could be one or the other, or both. I would look at the easy things first. Probably the ignition coil packs and power units. Once you rule them out, check for slipped timing.

The 24V have a pre-disposition for the rear exhaust cam slipping a tooth or two. It usually happens at start-up and is manifested by strong sulfur smell, lumpy idle, and smooth running above idle.
 

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Hopefully you can prove us wrong on cam timing issue.
 

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Here is photo of spark amplifier with pieces

:)First photo I took lookind down in front of LS into engine compartment showed where the round cannister fitted. Photos are mainly of it upside down, but look for it below the air cleaner box and between it and the engine itself. Look at the pictures and try to visualize the ensemble the other side up insted of from the bottom as the photos show. The two leads from the harnass from the ecu trigger the spark zap (taking the place of the distributor), but the spark has to be amplifed before it gets to coil packs over the tops of the spark plugs. So, swith the two leads and see if a different cylinder misses. Diagnose in that fashion as to which of the two amplifiers is bad. I do have that one still shown. I can send it to you if you want it. The other I have on my LS. This was from another car from which I took an engine that ran wonderfully in the new car too, so I know both of these were good. One of the photos clearly shows the Bosch part number. Only 24 valve engines have these. It is a specialized problem. I am trouble getting the photos on this post. I may have to try again. :) Jay
 

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Let me understand this a little better, if one of these units goes out, then you get no spark on one bank? How reliable are these units? How long do they generally last? I am thinking that I should probably get a couple of these units and put them on the shelf just incase this issue should come up. :)
 

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Spark Amplifier

These never fail completely. That is what is so frustrating. Instead they will fail to deliver enough spark for one cylinder of the three on one side, and then you worry what suddenly went wrong. It acts almost the same way the old Milano, Gtv6 or other six cylinder 164's do when there is a slightly slipped belt. But they don't fail all that often. That is what is so frustrating about them, and ONLY on 24 valve LS or Q which have the coil packs over the spark plugs. You need have only one spare, or a friend with a spare. Jay
 

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Obviously, the timing belt should have been tensioned upon installation. Dummy Ferrari "specialist". Do not forget to re-tension at 10,000 miles. This would certainly point to the timing belt slipping a bit, but it sounds like something else since the problem went from one bank to the other upon flipping the ignition modules. At least that's what I *think* he said -- just starting my first cup of coffee.
 

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Obviously, the timing belt should have been tensioned upon installation. Dummy Ferrari "specialist". Do not forget to re-tension at 10,000 miles. This would certainly point to the timing belt slipping a bit, but it sounds like something else since the problem went from one bank to the other upon flipping the ignition modules. At least that's what I *think* he said -- just starting my first cup of coffee.

Jay said he had that problem not original poster.
 

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Discussion Starter #15
Lets Be Clear About one Thing

The guy who works on my car is top notch. I know good from bad. Bad was the former Alfa dealer with the factory trained technician where I took the car as soon as I bought it for a new timing belt. I thought they would have all the special tools and do it right.

Wrong moosebreath. From looking at the car, it appears that rather than pull the cam covers and apply the cam locks, they simply locked the cam shafts down where they were with vice grips and r & r'd the belt. One cam was advanced and two others were retarded. None of them were off by a full tooth, so there was no reason to believe that the belt had slipped.

Jeff got the dies, timed the cams correctly, but concluded that with less than 4k miles on it and no evidence of past slipping that the belt didn't need re-tensioning. I don't blame him for any problem with belt tension, but rather the former dealer who plainly did nothing right (and oh by the way charged me an arm and a leg). To that shop, I will not be going back. I hope Alfa doesn't sign them up again if they ever get around to coming back.

As to whether it is timing or the spark amplifier, I guess we should check out both theories, starting with the least expensive. Jay's generous offer to lend me a known good amplifier seems to make this a no-brainer.

Thanks, Jay! I'll be in touch shortly.

Rex in Albany
 
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