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The other is of how I have to set the distributor to start the car. I feel like the slightly off position of things is supposed to tell me something but I cant quite wrap my head around it. It's almost like TDC isn't where the crank pulley is saying it is.
That looks about the same position as both of our engines from memory. I don't think the rotors normally line up exactly with the mark. As I said earlier, the position of the oil pump drive cog will affect the position of the distributor. I think you have something else going on there. Have you tried a different AFM?
 

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Hows the car running now?

Poor Idle

Vacuum leaks?
Idle mixture too lean/too rich? (sensors)
Plug gaps too big?
Crankcase ventilator clogged
Dirty injectors?
Fuel pump relay faulty connections
 

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Discussion Starter #64
I'll get some pictures and maybe a video later today.

Idle is "fine" but only after setting up the TPS never to register throttle as closed. I realize this might not be optimal but now it is not bunny hopping at parking lot speeds. By "fine" I mean it idles as well as the other GTV6 with same model C&B cams.

I have not tried a different AFM. There is no oxygen sensor.
 

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I have not tried a different AFM. There is no oxygen sensor.
Can you try the AFM off the other GTV6 and see what happens? With the 75/Milano even after replacing the faulty fuel pressure regulator and curing the flooding, it was still running very rough and was hard to start. I had fitted an AFM a friend gave me, due to the original one being a bit gouged around the neck. My mechanic suggested putting the original back on and sure enough it fired up instantly and purred like a kitten! The replacement AFM was faulty.
 

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Discussion Starter #67
It's not that it is running like a bag of empty beer cans, it isn't any longer. It's that I have no reference for setting ignition so it can run as well as it is supposed to. There was some misfiring between 5k and 6k but the audio isn't picking it up very well.




Some under hood pictures...
 

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But Mad North-Northwest
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It's not that it is running like a bag of empty beer cans, it isn't any longer. It's that I have no reference for setting ignition so it can run as well as it is supposed to.
There's no TDC mark on the pulley to time to? The 3.0 should be something 7 degrees BTDC at idle, at least for the US cars.

The proper distributor should give you an additional 12 degrees of vacuum advance, with ported (not plenum) vacuum from the throttle body. That is, no vacuum at idle (so no advance at idle), just vacuum when you open the throttle plate.

The electronic ignition advance unit also provides some amount of RPM-based advance when above idle, but I can't find a spec for that.

Beyond that, I might try testing with a proper 3.0 AFM. Can't say the BMW one is contributing to the running issues, but it's not the right part and was probably a poorly-considered attempt by the PO to get more power. It is probably not the right output curve for your engine.

Did the L-jet V6 not come with an oxygen sensor in Sweden? They all did here in the US. If it was originally an oxygen sensor setup and the PO removed the oxygen sensor (again, in a poorly-considered attempt to get more power) that might explain some of the running/idling issues. At least in the US, the 3.0 L-Jetronic engines use the oxygen sensor output to control the idle mixture.
 

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Discussion Starter #69
There's no TDC mark on the pulley to time to? The 3.0 should be something 7 degrees BTDC at idle, at least for the US cars.
There is but it won't start if I time according to it as per manual.


Did the L-jet V6 not come with an oxygen sensor in Sweden? They all did here in the US. If it was originally an oxygen sensor setup and the PO removed the oxygen sensor (again, in a poorly-considered attempt to get more power) that might explain some of the running/idling issues. At least in the US, the 3.0 L-Jetronic engines use the oxygen sensor output to control the idle mixture.
No GTV6 came here with oxygen sensor. 75/Milano seems all had them except some 3 liters that were initially headed elsewhere (Finland?), according to legend.

A vacuum advance or retard distributor is now fitted to the car, I don't know yet which version it is but I have throttle houses of either setup. Only time is lacking, inspection is planned for friday but it is looking bleak right know. Must also sort speedometer and high beam until then.

Friday the 10th - DOT-man Cometh
 

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As I understand it you have to use the BMW computer as well as the AFM in order to get it to run anywhere near correctly. Did the PO do that? If it was me i would definitely swap the standard AFM off the other car onto it to see what happens. I spent three weeks chasing the poor running with the 75 and knowing what I know now I would have checked the regulator early on and stuck with the original AFM. If you already have an AFM available on another car, why not try it? You have nothing to lose and at least you would have either solved the problem or eliminated that possible cause.
 

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Discussion Starter #71
I might, if everything hooks up without further modification. Friday's inspection is out but vacation starts on Monday which should give me some extra time to put into this.
 

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But Mad North-Northwest
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I think that's worth doing.

The timing mark thing also seems really weird to me. It's a bit of a hassle, but at this point it's probably worth pulling the valve covers and rotating the engine to TDC to make sure the marks all line up. You can put a pencil down the cylinder 1 spark plug hole to make sure the piston is at the top. It just seems really screwed up that you can't time the engine to the mark on the pulley, and I'm trying to figure out if that's an issue with the ignition system or a physical issue with the engine timing marks.
 

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If cars been running with the wrong mixture settings for periods you should check yours plugs. they will foul up. yes

Old school method is to take car out and run it at full tit switch of engine straight after it is at full revs, pull in and check plugs.

The bigger AFM is probably making your mixture too lean at high revs if it's from a bigger engine. As well as not being in the right advance curve for the alfa.

Could you show us more of the engine bay. A picture of the whole engine bay from each side showing what has been taken off or put on by PO's

If it's got a catalytic converter on it and it's been running with bad fuel/air mixture you might find it's damaged, Unburnt fuel will ignite melting parts inside.

You could try take off oxygen sensor, if you notice a marked change in performance. This could be what's causing poor acceleration. Too much back pressure.

Best solution is go back to Alfa setup.
 

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As I keep saying, it is easy to find out what the situation is here:

1. Compare the computer in this car with the one in the other car.
2. If it is the same, fit the AFM from the other car and it should work properly.
3. If the computer is indeed a BMW one, (and I bet it isn't), swap the one off the other car in there and try it, along with the AFM.
4. If you want the BMW AFM to work, you need to read threads by Greg Gordon and others to find out what you need to do to get it to work. Personally, I wouldn't bother going to the trouble because the small difference it might make isn't worth the trouble. I have looked into it in detail recently because I was thinking of doing the conversion on our 3 litre project car and decided not to bother.

This will cost you nothing and you will have a better idea of what's going on.
 

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Discussion Starter #76
Car and I got through inspection today*, only issue was the speedometer which I have 30 days to fix.

Immediately after that I went on a two hour drive on twisty roads to get a feel for it. It runs fine under load and when coasting but it stumbles when under light throttle. The spare throttle I had with the correct vacuum port had a different wire pulley and parts were nor interchangeable, I am now taking vacuum from the attachments on the plenum. This port has a larger diameter and I assume this might affect ignition advance stability when near closed throttle. Or it's something unrelated, like the TPS that I played around with. Anyway, this means it is now starting when timed with the light. Yay!

Also, the o-ring in the idle adjustment valve was missing. I will try and check every point of the list over the next few days, will probably avoid lifting the valve covers again unless I have to. Threads have seen their use-by-date...

*Meaning I can test drive it legally.
 

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But Mad North-Northwest
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That's a Tip Top!

"Ice cream with soft cocoa filling, waffle, coated with milk chocolate flavor and roasted puffed rice."
Truly Sweden is the land of the gods!

Pulling distributor vacuum off the plenum may be part of your throttle problem. If you have the later distributor it has a vacuum advance. The setup for this should be that there is NO vacuum advance at idle, and that advance comes on immediately as you open the throttle (it pulls vacuum just upstream of the throttle plate).

If you go to the V6 L-jet guide at hiperformancestore.com there are some details on the two setups. If you're mixing and matching parts between the two it may take some testing and thinking to figure out what you've got and how to properly set it up.

Yeah, the valve cover bolt holes are easy to strip. I learned the hard way not to go by the torque specs in the book. Just snug them down. Fortunately they're pretty easy to do a helicoil repair on (they're M7x1.0, if I recall correctly).
 

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Discussion Starter #80
1st. I check and double check ignition timing. I try "sligtly off" timing in both directions but there is no change. I fit a restrictor to the vacuum tube, similar in size to the proper trottle housing port. No effect.

2nd. I have tried a different ECU, one that came with the car along with a lot of other stuff. It has "GTV6 -84 3.3 Cosworth" scribbled on it. Starts but didn't work very well, I would love to know where the rest of that engine is though.

3rd. Later on I try on a different BMW AFM, one that I purchased for the black car years ago but never got around to fit. Worked even worse. Then I realise (finds in other part bin) that I have an non-tampered-with 2.5 AFM. I fit this and it runs near perfectly. There is still the constant bunny hopping under light load and stepping of the gas completely almost kills it before it finds idle speed. There is less smoke. When first dismounting the original AFM I get a further surprise.

Includes a pic of the inside of the AFM, the one on the black car is modified in a similar manner. I am manipulating the flap to show where I think the path is looking worn.
 

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