Alfa Romeo Forums banner

1 - 20 of 53 Posts

·
Registered
Joined
·
188 Posts
Discussion Starter #1 (Edited)
[UPDATE!] I would like to apologise to Adaptronic for suggesting, however obliquely, that there was anything wrong with their ECU. The engine had simply been incorrectly reassembled by the mechanic. The car now runs very nicely.


Hi all,

I am at a crossroads. The PO put an ECU in my GTV6 and the time has come to dump it. The choice is either go with a state-of-the-art new ECU and harness, or go back to "originale" with the air-flow meter etc.

What is "wrong" with the original AFM and injection system? Pro: it makes the car more original. Con... ?

I assume with a properly installed and set up ECU I will get better fuel economy but that's a low priority. I just want my car to idle smoothly and cruise nicely without any lumpiness.

Any advice much appreciated!
 

·
Registered
Joined
·
1,198 Posts
What kind of ECU is it? What's wrong with it that requires the need to dump it?
Might only need a decent tune at a shop who can do it right.

But, if there is a real problem that can't really be fixed, I'd just switch back to original set up unless you want to chase power or something.
 

·
Registered
Joined
·
3,359 Posts
Do you know what mods (if any) were made to the engine? Some might require the aftermarket ECU, if there were none then it won't matter.

Kevin
 

·
Registered
Joined
·
1,750 Posts
Hi all,

I am at a crossroads. The PO put a budget ECU in my GTV6 and the time has come to dump it. The choice is either go with a state-of-the-art new ECU and harness, or go back to "originale" with the air-flow meter etc.
More information about what you have currently installed in your car is needed.

What is "wrong" with the original AFM and injection system? Pro: it makes the car more original. Con... ?
What is very real about the L Jetronic is its age.
Not only is the original set up old, with it's auxiliary air valve, cold start injector and vane AFM (which has moving and rubbing parts), all of the components that make up the system are OLD.
I don't know if anyone has looked at them in the Jetronic, but I know that the capacitors in Toyota ECU's get old and leak their electrolyte fluid. This changes the capacitor's behaviour and so changes the behaviour of the ECU.
On top of that, the plastic Bosch plugs get very brittle (and their retaining clips are a PITA).

I assume with a properly installed and set up ECU I will get better fuel economy but that's a low priority. I just want my car to idle smoothly and cruise nicely without any lumpiness.

Any advice much appreciated!
1 advantage of going for a decent programmable ECU is being able to, at bare minimum, fire the injectors in (their correctly matched) pairs. Or if you're prepared to do/have done for you, the required work, go full sequential. Tho full sequential isn't really going to be a big improvement unless you are using significantly bigger injectors to support a significant increase in performance from engine upgrades.
Throwing the (probably) restrictive air flow meter in the bin is a plus, too.

Potentially you can get better fuel economy with a more capable ECU. Cruise fuel economy may not necessarily be improved (unless you specifically tune/have it tuned to cruise at leaner air/fuel ratios than the typical 14.7:1), but by being able to optimally tune your engine at each and every rev/load point, at any engine and inlet air temperature point as well as only tip in as much extra fuel as is needed for acceleration enrichment, then fuel economy improvement should be there.
Having full control of ignition timing is a huge benefit. Like tuning the fuel delivery, it will allow your engine to have the correct amount of ignition advance at any given operating condition.
And of course, if you make any changes to your engine, a programmable ECU will be much more capable of correctly and accurately accommodating those changes.
 

·
Premium Member
Joined
·
14,012 Posts
What is very real about the L Jetronic is its age.
That's right. In the early days of the ABB most of the requests for help with induction problems were from SPICA owners and now it seems like L-Jet owners are the ones with problems. The L-Jet stuff is not as reliable as it used to be.

but I know that the capacitors in Toyota ECU's get old and leak their electrolyte fluid. This changes the capacitor's behaviour and so changes the behaviour of the ECU.
Electrolytic capacitors are the leading cause of failure in older electronics equipment. They have a limited life span and it is not a question of if they will fail but when. One of my tasks when I worked for a living was overseeing a program to replace electrolytics in Honeywell control computers before they failed.
 

·
Registered
Joined
·
188 Posts
Discussion Starter #6
Thanks for all the info and advice guys, makes it a lot clearer.

My car has an older Adaptronic ECU in it (pre-USB) and while it might be fine, three different tuner shops have told me they won't touch it. Of course they are trying to sell me an end-to-end solution for $$$ and given I know so little about the setup in my car, I'm tempted.

I am pretty sure my ECU is an e420c. I do not know if the car is running in sequential mode or not - how can I tell?

Does anyone know this ECU? Is it as poor as the money-hungry tuners say? :)
 

·
Registered
Joined
·
1,198 Posts
I'm sure Adaptronic are the brand that Beninca pushes for ECU's. Call them up.

Still though, you haven't given a reason for why you want to dump it or what's going wrong with it? Just the tune [lumpiness that you mentioned could be a host of other things too]?

Edit:
The E420C is roughly 10 years old from what I gather, probably less unless it was installed at release date. It should be up to scratch for the job.

Here's a link to the installer manual. Might come in handy:
http://www.y8spec.com/adaptronic/Installers_V1.0.PDF

And a link to the tuning software at the Adaptronic website:
http://www.adaptronic.com.au/downloads/
 

·
Registered
Joined
·
188 Posts
Discussion Starter #8
Yes, the tune is pretty awful at the moment plus I don't know how it's been set up plus, as mentioned, everyone seems to hate Adaptronic, plus I'm stirring :).

Generally the car runs unevenly at idle and at very low throttle inputs. At suburban speeds (50 or 60 km/h) maintaining the speed limit is a bit unpleasant. Higher revs are fine and idling at speed (ie no pedal) is fine too.

Injectors have all just been replaced, one was leaking, idle is improved a bit as a result.

Ideally of course I would just like it tuned properly. Why do people hate Adaptronic?? It's not just raw naked "I can sell this guy a $4000 new ignition system" is it? IS IT?
 

·
Registered
Joined
·
1,198 Posts
I can't comment on the 'hate' but I've never heard bad about them. I only hear bad about megasquirt (but with firsthand experience on my own car, I love it and don't understand. Even compared to a friends Soarer with Haltech it seems great).

Adaptronic do have auto tune features. Maybe with learning about those features you could auto tune the cruising to smooth thing out.

Do you have a wideband oxygen gauge? I presume not. That might hold some handy info and feedback. Might be running lean or rich. Backfires at all?
 

·
Registered
Joined
·
1,750 Posts
The 420c is a very capable device.
If it is running rich, then it probably a tune problem, but making sure the installation is done well and that there are no sensor problems is a good start.

I'd suggest getting your hands on the required USB to serial port cable. Get 1 from a Jaycar outlet and make sure you get the correct serial cable end.
Download and install the tuning software WARI, hook the e40c up to your computer and check for faults and correctly calibrated analogue sensors.
You car does have an analogue TPS, doesn't it?
Make sure the injectors are paired together correctly.

BTW, any tuner who won't tune a decent ECU, regardless of the brand, isn't worth wasting your time and money on.
The hard work is in the configuration of the ECU to work with what ever crankshaft position monitoring, getting the ECU to understand the injectors behavior and calibration of the temperature sensors. TPS and MAP sensor calibration is quite straight forward, but idealy you have a calibrated gauge and a vacuum pump to calibrate the MAP sensor.
After ECU set up and analogue sensor calibration, it's really only acceleration enrichment that can be a bit of a PITA. But the Alfa's are such a straightforward engine (as most old engines are), that there won't be any unpleasant tuning surprises.
 

·
Registered
Joined
·
1,750 Posts
I should have mentioned.
Join the Adaptronic forum. Heaps of information on there and plenty fixes for weird niggles. The forum will also have the firmware updates first. They're not always necessary as a lot of the times firmware upgrades are to add new features. But plenty of upgrades are to fix little niggles in the firmware itself.

And if you have any problems or questions, even tho my e420c hasn't run my Alfa yet, I've used it with some decent success on my MR2, shoot me a PM and I'll help as best as I can.

BTW, when you get a serial to USB cable and plug your computer into the ECU, have a good look at the coolant temperature sensors calibration curve.
Here's the 1 in my Alfa's 420c and it's to suit the Bosch coolant temp sensor. Note that this is just the calibration curve and not what the ECU does coolant temp correction.
That's the second photo in the corrections folder/page of the ECU.

Understanding programmable ECU is just like learning anything new.
Research, reading and question asking.
The most important thing is believing that you can learn it. And leave the mockers, the knockers and the sceptics on the side of the road. Your car, your hobby and your sense of satisfaction. :wink2:
 

Attachments

·
Registered
Joined
·
188 Posts
Discussion Starter #14
Thanks Duk, appreciate the detail.

Today was not a good day, Alfa-wise. Maybe now it's time to tell the story of how the car seems to be getting worse and worse?

(and yes, I know this should have been the FIRST post in this thread, really! But this has been a cumulative problem.)


1. I bought rust-free car with new paint and leather interior, cosmetically beautiful, and the PO told me that the 2.5 engine was "good" but they were always planning to swap it for a 24V 3.0. Because of that, they had Beninca put the Adaptronic ECU in, lowered the car and put 147 GTA brakes on the front (what are these brakes actually called?)

2. The car was FULL of mechanical gremlins but I made them an offer that took this into account and began having the mechanic work through the problems. Lots of hoses to be replaced, radiator fans, the engine timing was fully retarded, etc etc... and the 2nd gear synchro was dodgy.

3. I drove the car for about 3 years, double-clutching to second and had a good time. Then the head gasket went. When we pulled the heads off, they were revealed to be extremely corroded. So the car now has refurbished heads that are not the original chunks of metal, but are still stock GTV6 heads.

4. New heads made a big difference but the car started vibrating in an odd manner about two weeks later. I took it back it and it became apparent the rear engine mount was completely worn away, and the new low-down power somehow twisted the bell housing at the back of the engine (is that the right term?) and cracked it.

5. Since they were pulling the engine out anyway, I decided to get the transmission overhauled too, and tailshaft balanced (this was a it's-off-the-road-anyway decision, not a budget decision!). They used poor quality synchros that degraded incredibly quickly. 2nd became impossible to select when cold, even with double-clutching. Also, the manifold was leaking air and making a weird "squeeeeeee" noise.

6. They kept the car for two weeks and replaced the synchros with better quality ones, to their credit, at their cost. Transmission is now good. They replaced the hose/gasket things (proper name please!) that connect the plenum to the engine with OEM units, stopping the wheeze. THey gave me the car back.

7. The car reeked of raw fuel and ran like crap. They kept saying "it's that computer mate, that computer needs to be remapped". I took it to a tuner who immediately said "Hey you've got a leaky injector." How did my mechanic miss a leaky injector (never mind that engine mount)?

8. The mechanic replaced the injectors at parts cost only, did not charge labour. A mate picked the car up for me and drove it home a couple of days ago. I only just got into it today and it runs like absolute crap. Really terrible at low throttle inputs. Exhaust sounds different. Lots of smoke, running very rich.

Writing all this down makes it sound like my mechanic, despite the fact they race GTV6s and have done the right thing charging me less than they technically could, have failed pretty badly to provide a "complete" service looking after the car - instead, it seems they just fix THE ONE THING I mention. Leaky injector? Replace injectors. PROBLEM FIXED. Oh you actually want the car to be driveable? Why didn't you say...

This is a warning to anyone who doesn't wrench their own car I guess!

Right now I have very little confidence that retuning would fix the issues. I really need to make them do a 100 point inspection or whatever to correctly diagnose the issue.

So, that's the background, here's the question:

If you tune an ECU to a motor that is in poor condition, maybe has a leaky head gasket, and then go and fix the heads and replace the injectors... could it be possible that the computer is now responding incorrectly to signals and running the motor too rich? Does that sound like a possible reason for this problem?

Or is it more likely to be mechanical?

Thanks!
 

·
Registered
Joined
·
1,750 Posts
You really, REALLY need to make sure that everything is done correctly in regards to ECU sensors being attached to the engine and plugged back into the ECU.
Find the MAP sensor and make absolutely sure that it is attached to the plenum chamber.
About the only thing the MAP sensor can be attached to in parallel, is the fuel pressure regulator. Also, make sure that it is attached correctly. If they are Tee'd into the same line as the charcoal canister, then that is wrong.
If either of these is plumbed incorrectly then they could cause some ugly over fueling. But the MAP sensor being incorrectly (or not at all) plumbed (or damaged if they were rough getting its signal line off of the nipple) will cause terrible running as the ECU will think the engine is at full throttle, even if the TPS says otherwise.

Grab as many photos of the engine bay, including all of the sensors and their wiring, as you can.

When I bought my dealer serviced F6, it came to me with with the factory blow off valve signal line disconnected (it has to be removed as part of the engine's intake plumbing when spark plugs are replaced). Maybe someone forgot. Maybe they didn't. :|
And "No" they don't just pop off.
 

·
Registered
Joined
·
188 Posts
Discussion Starter #16
Ah. After taking pictures of the engine bay the possibility of incorrect reassembly has become more likely.

I've uploaded a bunch of images to dropbox here:

https://www.dropbox.com/sh/ip14zz2piwhzwgv/AACAqp6QMVDQhTa8L26Hkiroa?dl=0

If anyone wants them in the thread, let me know! :)

Okay so when I sent the car in for the gearbox re-fix, I left a note saying "please tidy up exposed wires in cabin". Due perhaps to not really reading it, it appears the mechanics have spent several hours moving, zip-tying, cable-managing and more all the wires in the ENGINE bay.

The car ran fine (with a leaky plenum) before this extensive fiddling with wires which I did NOT ask for and which I probably paid several hundred bucks in labour for.

If anyone can spot anything amiss that would be great since I can just take it back to them and ask them to make it right.

Meanwhile this morning a lovely neighbour dropped by to complain about the noise of the car going up the hill... sigh.
 

·
Registered
Joined
·
1,750 Posts
Thanks for the photos.
Alfa Romeo engine bays are very difficult to make neat and tidy. And for some reason there is a lot of redundant stuff left in your's...........

Anyway.
1st photo is of what I believe to be the MAP sensor's wiring plug and at a guess, the red hose is the vacuum signal line. If it is, make sure the MAP sensor is plugged in electrically and that the red hose is attached to it and in good condition. The hose is a lot closer to the driver's side exhaust manifold than it should be. Make sure the hose hasn't started to perish due to the heat.

The second photo is of the cold start injector.
Now why anyone would use that in a car with a capable programmable ECU, I'll never know. Maybe so they didn't have to do any work to the plumbing (which they clearly didn't). If the injector is somehow being switched on or is leaking, then that could be a source of your excess fueling.
You could simply unplug it and see what it's like.
I don't have any experience with the old L Jetronic EFI, but I do know that the old Toyota 4AGZE (from my supercharged MR2) which was often said to have an LH Jetronic ECU, also used a cold start injector that is controlled by simple contraption. That is, they're not controlled by the original ECU itself. Maybe the cold start controller is still in the car and was simply left unplugged by who ever installed the Adaptonic. And maybe your mechanic simply plugged it back in thinking they were doing the right thing.
This assumes (dangerous I know :wink2: ) that the Adaptronic has any cold engine enrichment programmed into it.
Looking at the set up in the Adaptronic is a really good idea and would help a lot.
 

Attachments

·
Registered
Joined
·
188 Posts
Discussion Starter #18
Fantastic. I've unplugged the Cold Start injector and it has improved things - still not perfect, but much better. I had already noticed the constant "pssht pssht pssht" noise and was going to ask about that in a future post.

In previous years, it has only made that noise when actually cold.

Still need to get that cable to check the actual ECU too. Shopping time!

Meanwhile, I've uploaded three more pics regarding the hose and the infamous "green plug". This green plug occasionally prevents the car from starting (engine doesn't fire) - if I unplug it, blow on it, and plug it back it in works. Computer style! I asked the mechanic to fix it, their solution was to tie it down with cable-ties :(.

The red pipe goes under that green plug and its module and attaches to a ratty old hose that disappears into the firewall. I hazard to guess that this is wrong. They are connected via a little thingie that has a screw but it appears to be fully open and unobstructed.

High res pics are on the dropbox.
 

Attachments

·
Registered
Joined
·
1,750 Posts
Meanwhile, I've uploaded three more pics regarding the hose and the infamous "green plug". This green plug occasionally prevents the car from starting (engine doesn't fire) - if I unplug it, blow on it, and plug it back it in works. Computer style! I asked the mechanic to fix it, their solution was to tie it down with cable-ties :(.

The red pipe goes under that green plug and its module and attaches to a ratty old hose that disappears into the firewall. I hazard to guess that this is wrong. They are connected via a little thingie that has a screw but it appears to be fully open and unobstructed.
Now we're getting somewhere! :grin2:

So the green plug is definitely attached to the MAP sensor.
The fact that it misbehaves electrically is a worry. Typically when those Delco sensors are bought, they come with a pre-crimped plug and people solder and insulate the connection. Now that's not an ideal way to do it as car manufacturers avoid soldered electrical connection in the wiring loom like the plague. Alternatively, the plugs can be bought (They're the same as the NARVA 3 pin water proof plugs. Tho they aren't made by NARVA and you can get them for a fraction of the cost on ebay............. :wink2: ) and the pins crimped on directly. This is preferred.
I'd suggest some exploratory surgery in that bit of wiring. Remove the electrical tape, peel off the split loom tubing and look for any joined wires. Inspect the plug itself and see if the wires move around in the pins. When crimped with the correct tool, the pins are very firmly attached to the wire. Unfortunately getting the correct tool is harder than it should be..............

As for the hose. Well, that should only go to the map sensor and nothing else. Just as a test, grab some new vacuum type hose of the correct size and plumb it directly from the plenum chamber to the MAP sensor. Be a bit careful getting the hose of the MAP sensors nipple as they can get a bit brittle with age. Twist the hose 1st to help it loosen any stickyness.
 
1 - 20 of 53 Posts
Top