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>Have checked the auxiliary air valve ... its open but gives no signal...is it supposed to give out any?

No the AAV does not give out any signal. It has a heating element in it, when the engine starts 12V is supplied to the terminals so that it closes quicker than by engine heat alone. It acts like a choke.

I'd hazard a guess that it is the AFM or the Throttle Position Sensor is causing the issue. Then again it could be stuck injector(s) constantly spraying fuel or some other faulty sensor(!).

TTS - makes the cold start injector squirt when the engine starts - could cause rich running.
AFM - meters the air - if it is faulty the ECU may be getting the wrong signal and sensing too much air.
TPS - senses the throttle position - if the microswitch is faulty it could think it is WOT which would inject the maximum amount of fuel.

Of course that list is not exhaustive and there are plenty of other things to look at.

Since your engine runs extremely rich and introducing unmetered air seems to get it going I'd focus on the AFM first and ensure it is working properly.
 

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See my signature to a page of info about the L-jetronic system in the GTV6.

A couple of questions about the photo you posted. And a photo of the engine bay of our 1981 GTV6. Note that I put in a manual AAV.
 

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We need to see CLEAR pictures. For instance, a picture where a person isn't blocking the key components of the engine. Also try to make sure the picture isn't blurry. Finally, shining a light into the engine bay, on the components of the engine so that we can see them is also a good idea.

Where is the breather that is supposed to be on the valve cover?
 

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Discussion Starter #164
yes of course. did some research on my own. Checked the vaccum ... the one to the distributor appears to be slightly too narrow The grounds.. especially the one at the front form the drivers side head to the body was missing as well as the ground between the plenum chamber and the valve cover. Have asked for that to be put on and then will check back with you guys. Alos with better pics.
 

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>Have checked the auxiliary air valve ... its open but gives no signal...is it supposed to give out any?


TPS - senses the throttle position - if the microswitch is faulty it could think it is WOT which would inject the maximum amount of fuel.

Of course that list is not exhaustive and there are plenty of other things to look at.
This is not correct---the WOT switch of the throttle switch simply tells the ECU to ignore the O2 sensor signal and enter "open-loop" mode. Otherwise it just reads from the base map in the ECU, which will be slightly rich at higher engine load, but not pig-rich.

I would start by checking fuel pressure---a pinched return line or hose could cause this no matter which sensors are or aren't working.
 

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Discussion Starter #166
three earth lines were missing. these were put in and grounding of the injectors and the plenum done. the AAv was installed. The engine started but started all right with a bit of churning...less than before but was still pig rich....disconnected the vaccum line from the head to the AAVd high but became much less rich....but would not idle

I need time here... will check the AAv ... the ambient temperature is about 30 celsius and the AAV although one can blow in and out appears almost closed....one cannot see through it... no daylight.

I do take your point about fuel pressure...next thing to check.
 

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This is not correct---the WOT switch of the throttle switch simply tells the ECU to ignore the O2 sensor signal and enter "open-loop" mode. Otherwise it just reads from the base map in the ECU, which will be slightly rich at higher engine load, but not pig-rich.

I would start by checking fuel pressure---a pinched return line or hose could cause this no matter which sensors are or aren't working.
OK, but early euro spec GTV6s do not have an O2 sensor. On these cars the WOT only tells the ECU to use a specific injector timing which is somewhat rich under load. If the engine is not under load (like idling) and the WOT injector timing is used I would assume this would be very rich (I haven't tried it).

Certainly there are many ways to get an overly rich mixture including too high fuel pressure and/or leaky injectors.

The AFM is pretty critical to the mixture as it measures both the air temperature and air flow to calculate the air mass. If the ECU is sensing too much air due to a bad AFM sensor, bad AFM wiper, bad previous owner adjustment or bad AFM spring then the mixture would be too rich. Which is why the AFM isn't a bad place to look.

No point in guessing - just need to go through the Greg Gordon checklist that ghnl posted.
 

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You’ve got an early euro setup, hence the lack of oil catch on the breather mentioned in post 162 by gnhl. Also the lack of an O2 sensor as tpalfa says.

One thing I’m a little concerned about is the routing of the AFM connection. In the same post you can see on gnhl’s car that the loom connects to the AFM from the rear, located by the open circular fitting next to it. On your car that cable seems to be routed around the front of the AFM, which makes me wonder if it’s actually connected correctly. Understand that it’s designed to only connect the right way but these engines will start and run with that connector unplugged. They just run full rich, with no loop back circuit to tell the ECU that anything’s wrong. No cat either BTW - for US peoples benefit.
 

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OK, but early euro spec GTV6s do not have an O2 sensor. On these cars the WOT only tells the ECU to use a specific injector timing which is somewhat rich under load. If the engine is not under load (like idling) and the WOT injector timing is used I would assume this would be very rich (I haven't tried it).

Certainly there are many ways to get an overly rich mixture including too high fuel pressure and/or leaky injectors.

The AFM is pretty critical to the mixture as it measures both the air temperature and air flow to calculate the air mass. If the ECU is sensing too much air due to a bad AFM sensor, bad AFM wiper, bad previous owner adjustment or bad AFM spring then the mixture would be too rich. Which is why the AFM isn't a bad place to look.

No point in guessing - just need to go through the Greg Gordon checklist that ghnl posted.
I wasn't implying that your other suggestions besides the throttle switch are invalid----of course the AFM is quite important. But the basics need to be checked first, and fuel pressure should be first on the list in case of an extreme rich running situation, especially in the case of a hodgepodge car such as this (no offense intended, but it was pieced together from several different cars!). Then check if the AAV is stuck closed, cold start injector leaking, etc, then go after the relevant sensors/wiring.

Same thing with a lean condition. Vacuum leaks and obvious mechanical stuff (AND fuel pressure/delivery volume) should be checked before going after the usual sensor test plan.
 

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Discussion Starter #170
Disaster strikes

As you will recall the engine was starting and not holding idle. The AAv valve was stuck closed and there were other weird problems.....smoking and running rich etc.
Well ….after fixing a few things the engine started but on giving throttle....observers tell me very high revs suddenly there was a clatter and guess what the cam belt slipped a tooth or two and I am left with bent valves on the left hand cylinder head and fractured cam cap????

This is a 3.0 litre and there seem to be no 3.0 litre heads available...so the 2.5 litre is being dusted out and cleaned.....shute...what can I say

Anyone with spare 3.0 litre heads???
 

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Sorry to read about your troubles after all the work you put into it.
I have seen a few 3.0 engines come and go on facebook pages (mainly out of the UK), I believe mostly out of south africa and abandonded 164's.
I have driven a 2.5 and while it will not world speed records, it is a sweet high revving engine with enough torque. Suggest you scout through UK facebook groups if a 3.0 is a must.

Sent from my F8332 using Tapatalk
 

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Discussion Starter #172
2.5 litre v6 in...3.0 litre out

Decided to put in the original 2.5 litre. HAs been satrted after a new ( used AAV) new thermotime switch and temperature sensor. The old AFM is being used and the engine started and became stable after the AFM had a paper put in as some pics and the movie will show if I am able to upload it. ,,,,no mp4 not supported

However the valve seals and the rings appear to be weak and there is oil coming into the exhaust headers and its smoking badly but not over fuelling. Although maybe keeping the engine running for a few hours may stop the smoking there is some pressure blowback past the rings. So decided to have the 3.0 litre head done again... will need exhaust valves ... and a little bit of welding.

The bodywork will be completed before then .. Will post is a couple of more days.

I am happier now inspite of the delays
 

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Great to read you are now moving forward :)

Which ever size, they are all fantastic engines.
Pete
 

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Discussion Starter #175
Its alive.............

The hiatus has involved the following.....
the 3 litre was taken out and the 2.5 litre put in...it smoked when it started but would not take the throttle and bogged down when the throttle was opened up. Has the valve seals gone and possibly needed a bottom end rebuild as well.
Decision made to have the passenger side... ie the left side in RHD cars head done again...as the valves were bent ….the fractured camshaft retainer semicircular thingy ( sorry its not a human body part so I don't know what its called) was rewelded and even valve cotters were sourced ...locally....

The engine was put in and would flood again and start only when the fuel pump was disconnected form the fuel relay. would hold idle but only if the AFM had a paper insulating the throttle arc from the electronics. More head scratching ensued. The wiring was then taken out and reexamined.
The discovery was that the Thermotime switch wire to the CSV was shorting with another wire and the ECU was also playing up.....

Finally started with an AFM ending with 113 and the 3 litre ECU off a Euro/ British Alfa 75..... Both of the 2.5 litre Control Units played up … am having them opened up for repair...

The engine sound is a little bit tappety… needs adjustment...….but otherwise healthy.... no smoke …..ITS ALIVE

And finally a pic of the other Italian from the other firm and the German waiting for the GTV6 in the garage
 

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Discussion Starter #177
@PSk Yes Pete...its running …...the oil with the petrol mix after the rich mixture has been changed and the car has been run standing for several hours... no heating at the moment while stationery and its cool now … 17-19 Celsius so we will see. No smoking... its going to be fine … if the driveshaft balance isn't out...NOw for the next Alfa complication :)
 

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Discussion Starter #178
collecting it on Sunday?

greetings from a foggy Lahore.

I am told the car will be ready on Sunday but there are so many weddings going on that I may not be able to collect... so whats been the progress in the last few weeks.

As you may remember the car started....that it did but the engine sounds very tappety. The mechs say that its only one valve train where the intake valves cannot be adjusted having been prepared with a .5 mm gap and no shim adjustments. The broken head has been done with shims so can be adjusted and is not noisy... dont know.. I just want the car out and will get my own mech to sort it out.

The paint has been chipped in places. but very minor and will be sorted out tomorrow. The inner door handles have gone missing.... they are frantically searching.
Some issues... it needs the rear badges and gear lever knob has the polish chipped as well as the steering... fale wood over plastic may need to be done up in leather if it looks too bad.

some pics...and one pic of my latest.. a Jaguar XJ6 series 3. 4.2... one of only three series 3s in the country.
 

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