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Discussion Starter #21
Well, I don't remember if it showed that code because of inability of scanner to fully read the ECU, or because you have chosen incorrect ECU from the list.
You've picked the first option - Bosch diesel EDC16 CF4 1.9/2.4, correct?
Torque works, carscanner works, alfaobd connects but doesnt even return engine rpm data
 

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AlfaOBD then tries to connect via correct communication protocol (canbus or ISO-something), which your scanner does not support then.

Your other mentioned apps connects via some generic data bus, which is required for all car manufacturers, which provides some minimal required set of output data for engine emission systems diagnostics - some engine trouble codes, rpm, O2 sensor data etc... You know the drill - all the data available in Torque without custom PIDs.

Cheap Chinese ELM327 OBD adapter don't work with Alfas. The ones that work starts from 15-20 EUR usually (have more advanced microchips, higher quality circuit board and correct circuit design).
 

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Discussion Starter #23
AlfaOBD then tries to connect via correct communication protocol (canbus or ISO-something), which your scanner does not support then.

Your other mentioned apps connects via some generic data bus, which is required for all car manufacturers, which provides some minimal required set of output data for engine emission systems diagnostics - some engine trouble codes, rpm, O2 sensor data etc... You know the drill - all the data available in Torque without custom PIDs.

Cheap Chinese ELM327 OBD adapter don't work with Alfas. The ones that work starts from 15-20 EUR usually (have more advanced microchips, higher quality circuit board and correct circuit design).
Well **** then cause i paid 25 euros for it and its still the cheap chinese kind. Will buy another, have you got any recommandation? A link for a good one?
 

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OBDLink... but those are more like 40-50 EUR.. But are guaranteed to work.
Other nonamed ones are pretty much a lottery, unless you can find a recent review that they actually work correctly with Alfas.

You can try fixing yours - sometimes you just need to 'delete' one resistor on the circuit board for it to start working correctly with most modules.
Read more about it here: FAULTY ELM 327 INTERFACES DE-MYSTIFIED (READ HERE) - Multiecuscan
 

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Discussion Starter #25
OBDLink... but those are more like 40-50 EUR.. But are guaranteed to work.
Other nonamed ones are pretty much a lottery, unless you can find a recent review that they actually work correctly with Alfas.

You can try fixing yours - sometimes you just need to 'delete' one resistor on the circuit board for it to start working correctly with most modules.
Read more about it here: FAULTY ELM 327 INTERFACES DE-MYSTIFIED (READ HERE) - Multiecuscan
Thanks mate. Im going fricking insane, this morning the car started knocking and popping when taking slow speed corners or accelerating from a standstill. So guess its time to spend money again. 😐
 

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Just read through this and one thing that hasnt been mentioned is the vnt solenoid on the slam panel,. On both my last Diesels it has been leaking internally and giving a slugish turbo response. with a new one pick up from low revs is much better
Easy to test with a vacuum tester or just change it, they are about £40
 

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Discussion Starter #27
Just read through this and one thing that hasnt been mentioned is the vnt solenoid on the slam panel,. On both my last Diesels it has been leaking internally and giving a slugish turbo response. with a new one pick up from low revs is much better
Easy to test with a vacuum tester or just change it, they are about £40
Will check it. I'm taking it to a mechanic today, full scan and hopefully a vacuum test. It is now creaking awfully like a wheel is gonna fall off whenever starting from a dead stop, taking slow speed corners and braking at slow speed. It's been a dream to find out what owning an alfa is like🙃
 

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Discussion Starter #28
Will check it. I'm taking it to a mechanic today, full scan and hopefully a vacuum test. It is now creaking awfully like a wheel is gonna fall off whenever starting from a dead stop, taking slow speed corners and braking at slow speed. It's been a dream finding out what owning an alfa is like🙃
 

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They dont give a fault until they fail completely just leak internally so the vacuum leaks and doesn't work the vnt quick enough.
Easy to test with a vacuum tester
 

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Just read through this and one thing that hasnt been mentioned is the vnt solenoid on the slam panel,. On both my last Diesels it has been leaking internally and giving a slugish turbo response. with a new one pick up from low revs is much better
Easy to test with a vacuum tester or just change it, they are about £40
You can also take the cap off and clean the foam filter, could just be blocked


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Just read through this and one thing that hasnt been mentioned is the vnt solenoid on the slam panel,. On both my last Diesels it has been leaking internally and giving a slugish turbo response. with a new one pick up from low revs is much better
Easy to test with a vacuum tester or just change it, they are about £40
2nd post n75 on slam panel and vac hose check suggested😉
 

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Discussion Starter #32
Update: went to my mechanic, car just ended a regeneration when i arrived at his gate. Scanner hooked up, 0% clogging status, 0km since last regen. Turbo kicked in, it boosts to about 1.4 bars but is still sluggish nothing like i remember the car to be. Knocking sound caused by 2 bushings, that's an easy fix. Will insist on checking that n75 valve if car doesnt pick up in the next few days, at least it is now driveable.
 

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VNT valve (n75) is an easy job to do it yourself - just 2 vacuum hoses, 1 electrical connector and 2 nuts holding it.
After replacing mine, I have noticed more smoother power delivery - arrow on the turbo gauge was not jumping between values anymore, but were moving smoothly up and down..
Costed me around 20-25 EUR at the time.
 

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Discussion Starter #34
VNT valve (n75) is an easy job to do it yourself - just 2 vacuum hoses, 1 electrical connector and 2 nuts holding it.
After replacing mine, I have noticed more smoother power delivery - arrow on the turbo gauge was not jumping between values anymore, but were moving smoothly up and down..
Costed me around 20-25 EUR at the time.
If boost is sluggish but present it means no vacuum leaks present on the hoses right? If so that n75 valve should be the answer. Sticky vanes are excluded, it doesnt surge it's just sluggish plus turbo was cleaned and checked not even 7k km ago.
 

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If I'm not mistaken, turbo geometry in these cars is design in a way that it opens vanes to bypass compressor after certain rpm threshold, not the other way around when geometry is changed after firing an engine up, for better down low performance. If geometry is not working correctly - it registers overboost and can trigger limp mode. You would have a pending error code for that.

So in theory, there should be response from turbo at lower rpm and lack of performance at higher rpm. Think it actuated vanes to bypass at 2 or 2,5k rpm.

Regarding leaks from vacuum lines - you cannot say for sure, unless you test them.
 

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Discussion Starter #36
If I'm not mistaken, turbo geometry in these cars is design in a way that it opens vanes to bypass compressor after certain rpm threshold, not the other way around when geometry is changed after firing an engine up, for better down low performance. If geometry is not working correctly - it registers overboost and can trigger limp mode. You would have a pending error code for that.

So in theory, there should be response from turbo at lower rpm and lack of performance at higher rpm. Think it actuated vanes to bypass at 2 or 2,5k rpm.

Regarding leaks from vacuum lines - you cannot say for sure, unless you test them.
Thank you. Will sort it out and keep you guys posted.
 

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If I'm not mistaken, turbo geometry in these cars is design in a way that it opens vanes to bypass compressor after certain rpm threshold, not the other way around when geometry is changed after firing an engine up, for better down low performance. If geometry is not working correctly - it registers overboost and can trigger limp mode. You would have a pending error code for that.

So in theory, there should be response from turbo at lower rpm and lack of performance at higher rpm. Think it actuated vanes to bypass at 2 or 2,5k rpm.

Regarding leaks from vacuum lines - you cannot say for sure, unless you test them.
can go either way with sticking vanes when first starting vanes are set for max boost and as desired boost reached they move to divert exhaust gas away from turbine. If they are sticky and not fully operating to max body position some gas that is needed to spin up turbo is diverted so you can have lack of boost. Likewise if they are sticking when they should be controlling boost then you can have overboost.

quick and simple test is identify vnt actuator with engine off should be on its stop,start engine and actuator should move to max position and sit there while idling. It does not tell full story though all it’s doing is checking it has full range of movement. Ideally you want to disconnect actuator and move the rod to feel if it’s nice and smooth through whole range of movement.

testing vac is easily done with hand vac pump,you can check vanes move at correct vac reading along with the actuator holding a vacuum
 

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DPF reading is suspicious too....even brand new ones dont read 0% clog....and they never go much below 17 to 20 percent even after a really good regen.
 

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Discussion Starter #39
DPF reading is suspicious too....even brand new ones dont read 0% clog....and they never go much below 17 to 20 percent even after a really good regen.
****. Maybe the differential pressure sensor is toast? Just took out my MAP sensor to give it another clean. Guess what? It was broken off it just came out easily, rubber o ring and the plastic cage on it's tip were stuck in the manifold hole. Tried to fish out the plastic cage but it fell into the intake manifold. Is it safe to replace the map sensor and start the car with the plastic cage inside the manifold? Could i damage something?
 
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