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Discussion Starter #1 (Edited)
A fellow Alfisti was running out of storage space so now I have a second GTV6. It has a 3 liter from a 75/Milano with S2 cams and the larger AFM from one of those german cars. That's about all I now about it this far. Problem is, it is not running very well, hesitates both when under load and when not. Also Idle is funny, see this clip:

www.youtube.com/watch?v=WNo-bIZGGuE

My foot is off the pedal and it keeps doing that.

I went to check ignition timing but found two things, there is no vacuum advance and I can not see any markings on the pulley with the light hooked up to No.1 cylinder.

Supposedly a faulty TPS will affect idle but this one is a little too regular in it's behaviour I think.

Any suggestions? I hope to get a second look at it during the weekend but any pointers are appreciated.

Kind regards,
 

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I don't have any experience with the L Jettronic, but I'd definitely be making sure that the TPS is working and adjusted correctly.

As for ignition timing, does the engine actually have markings on the crank pulley for ignition advance?
Maybe double check that all of the cam timing marks line up and then do a static ignition timing set up.

After that, if pain still persists, the bigger AFM will be the next thing to deal with........................
I fitted a larger vane/flap AFM to 1 of my cars and used a programmable voltage signal modifyer to sort out the bigger AFM's signal to suit.
What I found was that signal change requirements weren't very linear. I could deal with it with programmable signal modifyer, but I really doubt that setting some rudimentry flap spring tension would give anything resembling a decent result.
 

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Discussion Starter #4
I'll look at the TPS first then, at least it is easy to get to. Thanks guys.

As for ignition timing, does the engine actually have markings on the crank pulley for ignition advance?
I thought it would have. It does on the black GTV6 and on a spare 2.5 Milano V6 I have. I some how need to be able to set ignition timing after a timing belt change, no? Or should I be looking for a CPS also? Don't have that on the other ones...
 

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I thought it would have. It does on the black GTV6 and on a spare 2.5 Milano V6 I have. I some how need to be able to set ignition timing after a timing belt change, no? Or should I be looking for a CPS also? Don't have that on the other ones...
Sorry, I can't comment on the L-Jet V6, my only experience is with the Motronic run V6. And they have a fixed crank angle sensor, and so fixed ignition timing and no marks on the crank pulley other than the TDC mark for cam timing.
 

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Discussion Starter #7
Found'em! Markings were way over in next county were the ignition light couldn't find them. Corrected it and good lord, it's a monster!! U-turns are 540 degrees from now on. :grin2:

No film of that, sorry...

Idle is still acting up though. It seems the TPS is fine but possibly to tightly adjusted, if I put my finger on the throttle linkage then idle is fine but if left alone it is working itself into "open" position (from vibration?) only to close itself again when almost stalling, and repeat. Curious. But I could not get to the lower screw with my key and i don't have a socket that size so I haven't tried that theory yet.
 

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What does it do? Did you unplug the CTS (on the thermostat housing) by mistake? Had you started it a couple times after you played with the timing? Also check that the cold start injector is in and firing, maybe you were able to hot start OK with the new timing but not cold?

Kevin
 

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Discussion Starter #11
Starter runs but there is not a hint of starting. No worrying mechanical sounds thankfully. Some times when letting it off the starter there is a hopeless "blubblub-blub" but nothing else. Fuel pump runs on manipulation of the flap, was not able to check for spark today.

Backstory: It died on me after getting it home on thursday. Friday I fiddled with fuses and connectors and got it running. On sunday it starts but runs as poorly as before (hesitates and misfires) until I see to the timing. Now it's dead again.

I took a quick run around the block to check for misfire (there were none) and then called it a day because I had to be somewhere. I don't recall turning it of before driving it back into the garage.
 

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Silly question, did you remember to tighten down the nut holding the distributor in place? My loosened up once and I was imagining all sorts of bad things that must have gone wrong for it to start running so poorly all of a sudden when I happened to grab the distributor to make sure it was tight and to my surprise it turned quite easily, at least it was an easy fix!

If that is not it did you happen to flood the engine? If you have spark then you might try starting in flood clear mode (cranking while the gas pedal is all the way down, press it before you start cranking not after or you may blow the plenum off). If it is flooded then it may take a couple tries in flood clear mode to get it running. If it was running fine and you shut it off normally then it probably isn't flooded, but if you were trying to start it or mucking around with it then it could be.

The other possibility is you still have a corrosion problem and it was just a temporary fix on Friday. Have you gone through the L-Jet pages?
L-jetronic Fuel Injection Technical Troubleshooting Article

Kevin
 

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Discussion Starter #13
I have two things, no spark and no idea.

Dead as door nail, not even a hint of life. I have checked the fuses, reset distributor according to workshop manual, poked connectors. I am at a loss, unless...

One of the senders on the thermostat housing is faulty looking. The connector part is flexing slightly in relation to the threaded part. I don't think it should do that. Question is, should failure of that sender affect ignition??

And front left ground. Why did I not go over it, I was looking at it...?

It was my plan to have this car sail through inspection next monday but that is looking bleak right now.

Those pages are great, saved me once with the black car.
 

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Discussion Starter #15
Correct. I hear ticking wich I assume is from injectors.

The one in the position of the EFI coolant temp sensor on the L-Jet page. Should be same but who knows?
 

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If you just hear clicking and the starter is not doing anything then it could be your ignition switch on the way out, but check the battery voltage first, if it is too low that can sometimes cause clicks.

If it is your ignition switch then one quick fix that can save a marginal switch is to add a starter relay. I wrote up how to do this on my website, did it on the Milano, can't remember now if I did it on my GTV6 but the idea is the same.

The coolant temp sensor (CTS) can cause a no start but it won't cause clicks, the engine will just keep turning over and won't catch. I think it can also cause rough running (the L-Jet page would say).

Kevin
 

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Discussion Starter #18
I have spark coming out of the coil but it's not getting through the distributor. I am trying to think of ways in which one could fail.
 

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I have spark coming out of the coil but it's not getting through the distributor. I am trying to think of ways in which one could fail.
Inspect the rotor button and distributor cap.
 

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It could be the wire from the ignition module to the distributor. That wire(S) tends to arc at the distributor connector. The wires, consist of a stranded insulated inner wire with a ground wire on the outside. If they touch at all ,you will have nada. The insulation at the connector has a tendency to recede allowing the ground to arc there. If it arcs intermittently, it results in rough running at idle when the voltage is low. I can send a photo of mine repaired if that helps?
 
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