Using elanscan

[Simon_P]

Hi Charlie,
I think that I your spray ether test won't work - The ECU is working to a target idle of 950 rpm if there is any change it is corrected by altering the IAC or the spark advance eg when the fans come on the revs don't drop.

If your ether spray made the revs increase the ECU would retard the timing / close the IAC. If it was closed loop it would also reduce the injector pulse to reduce the fuel input.

[Chas54]

Yeah, good point.

The MAP vac pipework was really crumbly and I thought it must be leaking but my easy start spray made no difference to engine revs. I think you've explained why now.
Anyway I changed that piece of pipe for new .

I am just off out to my garage now to chase around the earthing points and check vacuum pipes.

I should be posting my elan scan resuls later.

Regards
Charlie

[dapinky]

Chas,

If you run the engine at idle (not in service mode), and remove one of the vacuum pipes which you can get at easily, the revs should change slightly before settling down again. Basically, the sensors get 'confused' for a short time and then compensate for the new conditions.... if there is no change in revs, then there is no confusion, so it indicates that the vacuum system hasn't changed by the pipe removal...... which suggests that there is already another leak somewhere from a pipe/fitting.

If the revs change a bit, then it suggests that the rest of the vacuum pipes/fittings are complete.

[Chas54]

Dave
Thanks.
Yes I do get a change in revs when disconnecting a vac pipe.
I thought the MAP sensor , although new ,could be faulty but I connected a vacuum gauge on the manifold plenum outlet to the heater control vac reservoir. I figured I would disconnect the reservoir while trying to bottom this problem.
At idle I get 20" hg on my old vac gauge at idle, the MAP reading on elan scan shows a corresponding 0.34 bar. 20" is about 500mm. I think 1 bar (Atmospheric pressure) is about 750mm hg . If the manifold pulled another 250mm , I would be at pure vacuum so I think a 1/3 of a bar is accurate.

I have found a couple more dodgey vac hoses during this testing, The reservoir take off elbow at the plenum is cracked and the small hose to the fuel reg valve also cracked.

I tried a battery disconnect and then a short 30mph test drive to see if the IAC would learn where it should be , initial test shows CO around 6% still.

Simon has suggested the IAC position was incorrect and after my test drive this morning I think it improved from the position 2 to ten when warm.

I may try another run this afternoon .

I am going to put the elanscan data on here afterwards.

Regards
Charlie

[Chas54]

I have now run elanscan twice today

The second run is labelled exbury
The first 30mph reset.

I think the IAC position is now closer to 20 when running around 30mph.

If I remove a vac hose from the plenum the engine does pick up revs slightly

I have checked the earthing but all the joints are good on the off side of the plenum,

The idle speed seems ok to me but I am convinced the engine is still running rich. Its smells that way.

Again , gratefull if anyone can spot anything on my scans. And I still haven't worked out what Flags are .

Thanks for all the suggestions , they are helping me sift through this control system.

[Simon_P]

The first 30mph reset.

Notice the IAC going full range at 135 seconds and adjusting itself.

If I remove a vac hose from the plenum the engine does pick up revs slightly

As Dapinky says if you pull a vac hose off the revs should settle back again quickly. I didn't suggest that because at 2 clicks there is nothing left in the IAC before it is completely closed - Hence you get a rev rise as it is unable to compensate for the leak that you have created. I mentioned the fan as it would cause the IAC to open in order to compensate for the additional load of the fans.

I think the IAC position is now closer to 20 when running around 30mph.

The IAC should be 20 at idle. The reading at anything other than idle is a response to the conditions that the engine is experiencing. Looking at the end of your second scan the IAC is 5 at idle. This needs to be adjusted. To clarify this is nothing like adjusting a carburettor and you are not adjusting the idle, you are adjusting an air bleed so that the datum point for the IAC is 20. It needs to be 20 at Idle, so it is either maladjusted or you have a vacuum leak.
http://wikilec.com/view/Tickover

As mentioned earlier you also need to ensure that the base timing is correct. Again this is not adjusting the timing it is setting the Datum and it needs to be 16 degrees.
http://wikilec.com/view/Base_Timing

The idle speed seems ok to me

yes it is, but that is because the ECU is working to match the "engine speed" with "Target Idle" look at 1560 seconds in your scan and compare "engine speed" with "spark advance" the engine speed picks up and the ECU retards the advance to 2 degrees to slow it down. Now compare "engine speed" with "IAC position" notice that it also closes the IAC a three clicks to slow it down. Notice also that this is happening in a fraction of a second.

Looking again at the spark advance you will see that before this event it is around 16 degrees, that is what the ECU thinks is 16 degrees but the ECU has no way of knowing the actual timing and it could be anything. It relies on you setting the base timing to 16 degrees so that what it thinks is 16 degrees is actually 16 degrees.

Consider flags to be like switches they indicate conditions of things like A/C, PAS load, Fans on EGR open. As you can see we don't know what most of them are and for the time being you can ignore them.

[Simon_P]

I have found a couple more dodgey vac hoses during this testing, ...and the small hose to the fuel reg valve also cracked.

If you have less vacuum on the FPR the fuel pressure will be too high which might make it a bit rich

[Chas54]

Simon

Thanks , theres some really good stuff there. Also your post earlier this year explaining the difference between ignition timing and base timing.

I think my vacuum at the manifold is reasonable now at 0.35bar, this is around 35kpa and the manual states 30 to 40kpa at idle.
I have some new hosing on the way as I have used bits of odd clear tube I had laying around to do my testing.

I think ive found the IAC on the nearside lower part of the inlet plenum/manifold and the vacuum solenoid on the inside of the nearside front wing.

The adjustment screw , I think, being under a little black plastic plug.
I thought I would do as you suggest first though , and check the timing with a strobe in service mode.

I imagine the adjusting screw for the IAC would move the pintle valve seat further from the pintle , or vice versa in the other direction , But I don't understand why the adjustment wont be compensated for if the IAC position learning mode is entered in future. Would the valve not be stroked across its full range and these be reset as the new 0-80 ?

I have seen a service bulletin from 1995 suggesting my chip being a 9929 may not be able to meet current CO emission levels and there was an update made to 9930 that enabled a greater CO pot adjustment range. I am wondering if sometime in the future I will have to look at this >

Thanks again for your expertise with this .

I am off to Norfolk for a week on the Broads with family this weekend so you have a little respite from my queries.

regards
Charlie

[dapinky]

Charlie,

As you have now got your head around Elanscan (and most of what it means), and it is apparent from your posts that you are quite handy with bits and pieces around the car, can I offer you a suggestion?

To get the car into service mode you need to short out 2 of the pins on the connector..... which means that you can't then fit the elanscan plug......

...however, what I have done is to connect a simple rocker switch to a length of wire which has one end spliced to one wire at the back of the connector, and the other end spliced to the other wire. I fitted the switch into the roof of the glovebox, so to enter 'service mode' it is a simple case of flipping the switch (and it is reachable from the drivers seat). As it doesn't affect the actual connector face, Elanscan will still plug in (in fact, i leave my bluetooth adapter permanently fitted anyway).

It isn't usefull very often, but when it is, it's invaluable.

As you wish to fiddle with the air bleed screw to get the idle/IAC set correctly, you will need to be in 'service mode' (otherwise the other sensors will try to get it set at 925rpm anyway), and the dashboard tacho isn't always totally accurate, you can simply use elanscan in real-time mode to check the exact revs whilst it's in service mode.

Whilst you're there, it is also worth looking at what the throttle is doing - with no physical input, it should show 0.4V on the TPS and show 0% throttle (ignition on, engine not running!).... then put your foot all the way down to ensure that you are getting 100% throttle. When I changed my carpets/mats there was enough of an obstruction to the pedal movement to make it only go to 96%, so a quick adjustment at the engine end of the cable soon had full movement back (with enough slack still in the cable).

Both of these are quick and simple adjustments which may or may not make much difference (if needed), but all helps to have it right!

[Chas54]

Thanks Dave.

I was wondering about setting the IAC without seeing the results on elanscan . I can your switch is a rather good idea, particularly with all the grief I have at the moment.

I have just checked the base timing , largely because Simon P suggested it and he seems to be very knowledgeable about these things.He did write a really good explanation of the base timing and its effect on ignition timing in normal mode.

This was my first entering into service mode.

I struggled a bit to find the very slight notch on the crank pulley but now both the notch and the 16 degree before TDC mark are highlighted with white marker.

Anyway, entered service mode and the engine revs picked up slightly , remembered to cycle the revs above 2000 and back down slowly. Checked the timing marks and low and behold, I had a mere 8degrees BTDC. So I have now tweeked it to 16 degrees BTDC.

Now it says in wicki that the timings is invariably found wrong but I cant think why as I thought there was very little to wear out, unlike points on a distributor.

I have to try the IAC adjustment next but I thought I might try a dissconnection and reset first then a learning drive and see where things end up.

It may be just self delusion but the engine is ticking over slightly quieter.. I know when I start my Austin seven with the ignition lever retarded the whole things sounds noisey until I advance the lever a bit.

I may get tomorrow morning to test run the car , but then I have to leave all my toys and go on holiday

Thanks again

Charlie

[Chas54]

aa3.zip

idle after base timing and IA adjustment

(16.99 KiB) Downloaded 915 times

Gentlemen

After adjusting the base timing from 8 degrees to 16 BTDC , and (I think) getting on top of lots of bits of cracked vacuum hosing,
I have adjusted the idle air control screw !!

I had to screw in the adjusting screw 1 full turn. I initially turned it 1.5 turns to adjust the revs down in the service mode, whilst the dash rev counter showed around 950 on reconnecting the elan scan , it was down to 9250., Back to service mode and reduce by 1/2 turn and now its pretty close.

In normal mode now I am getting just bellow 2% CO on my gunson meter , whereas I was getting between 6 & 8 %..

I am attaching a stationary elanscan for any comments. I will be unable to try the car until next week.

I am feeling somewhat happier with the results and becoming more enlightend about the mysterious world of chipped control systems on the Elan.

Elanscan has become useful to me now, although I could do with a way of displaying more than two traces in the graph box .

So thanks Brit-car-nut, Dapinky and Simon P for all your advice and technical expertise.

I am still wondering why the base timing would be out so significantly and the Idle air screw, I can imagine that may travel on its own as it is not tight to adjust, I may try the locking mod on wiki.

I'm also thinking about dapinkys service mode switch although I might try one in the elanscan cable . Does it prevent elanscan reading any data having the service mode short on ?

Now I must also consider changing the memcal chip from 9929 to 9930 . Or perhaps as I am down to 2% CO I don't need it?

Regards
Charlie

[dapinky]

Charlie,

You are kind to mention my "expertise", but if you actually read what i put, very little has anything to do with actually interpretting the elanscan data - it really isn't my forte, but I use it as a good tool to tell me what other things are doing - There are far better guys on here at looking at results and actually knowing what they mean, and what to do to put things right!

I am pleased that your CO readings are a lot better, and I would suggest that as you can get within the readings required for the MOT (albeit that it isn't on a VOSA callibrated machine), then a 9930 chip replacement will be money spent for little result...... however, money spent to replace the chip with a 1499 chip and adding an O2 sensor will mean that you'll never have to worry about the emissions again, as they'll be down to something in the region of 0.5%...... and at that point (if you're changing the chip anyway), then there is little (if any) cost difference in getting the Everest version of the 1499..... and then it's a whole new ballgame of fun!

[Chas54]

Oh dear, more grief.

I thought I was on top of the CO. Came back from holiday had a quick run but it still feels like the engine is going to stall when pulling up.
Back to the CO meter and its reading 8 %.

I am certain I carried out my IAC adjustment in service mode. But I thought id check through again.

So in service mode I adjusted the IAC but I then decided I would have my first look at the CO pot.

I eventually located it after unbolting the memcal box. I took it off completely to check the range , about 10kohm to 0.4 ohm.

On refitting I set it to the counter clockwise position, ie fully unscrewed but before it has returned to 10kohm. so minimum resistance.

if I understand right , the resistance from the pot controls the voltage reference for the injector period.

so still in service mode, engine coolant on the fan cut out point , start screwing in the pot after about 2 turns co on the meter at the exhaust dropped gradually to just under 2% . That's good enough for me . But , now I know where the memcal is , and I know the chip 9929 isn't the updated one, I have ordered a new one from SJS.

Now a couple of day later I returned to the car , decided I would need the 30mph tootle round to ensure the IAC position is reset . Return home and measure the CO at 8.5%.

Unfortunately ive damaged my elan scan cable , I was looking for a position between the OBD plug and the little serial to usb chipboard convertor to insert a short for the service mode .

Ive ordered a new convertor from ebay which I hope will recover the elanscan tool.

I did notice that the CO pot connection plug would not stay together without the wire spring clip, it tends to fall apart if unsecure.

My current position is , I will wait for the new mamcal chip from SJS before attempting another CO pot adjustment , and ill put a slight bend in the CO pot plug pins to tighten up the fit. Ive got a caliper off at the rear at the moment so I wont be using the car for a while.

As before, any advice or inspirations on my wandering CO would be welcome

regards

Charlie

[Simon_P]

had a quick run but it still feels like the engine is going to stall when pulling up

I'll guess that you didn't disconnect the battery to reset the ECU. If you didn't it is still has the learnt value of 5 clicks. So you pull up to stop it goes to 5 clicks and with your new closed position on the bleed screw it required 20 clicks and isn't getting enough air.

Whenever you adjust something in service mode you need to reset the ECU.
1 Check
2 Adjust
3 Reset ECU
4 Go for tootle to relearn
5 Check... repeat

You should be able to check the idle by ear so Pinky's switch would help you to switch in and out of service mode easily.

[Chas54]

Simon

I think you may be right about me not correctly doing the reset by battery disconnection. Therefore I am not having the relearn process.

I am wondering if I am not fully depowering the system.

The car has an ancient Clifford alarm and immobiliser that is faulty in as much as the key fob doesn't work.(despite new fob battery)

So when I disconnect the car battery , the alarm goes off and I cant stop it but about 5 seconds latter the alarm back up battery must go flat as the alarm dies down and stops but when the main battery is reconnected, the immobilser is activated and I enter a code by pressing sequentially the little button that is near the digital clock.

Im sure I did a battery disconnect when I set the CO pot and Idle air control screw last week but. I will I think give it another go .

I have the NS rear caliper off at present waiting for repair kit. Hopefully I will finnish this, remake an elanscan cable and receive my updated memcal chip in the next couple of days , although I may wait before fitting the new memcal . I had hoped to get the CO correct or at least closer to required before introducing a whole new variable.

I think, as I have twice done this now, I can get the CO right . It appears that when I then take the car for a drive it reverts to the 8.5% CO . It does seem its the relearn where I am failing.

Thanks for your suggestions

Regards
Charlie

[Simon_P]

You need to allow 10 seconds after switching off the engine to allow the IAC to park.
Then
Disconnect the battery and count to 10 (or longer) before reconnecting. Turn the headlights on to pull down any stray voltage from the alarm.

I see from your scan that IAC is now at 15. Better but it should be 20 so something is not quite right.

As a thought check the correct plumbing for the Evaporative Emissions purge - if it is plumbed up wrong you could have a vacuum leak and be pulling in fuel vapour - there is a diagram and a description in the manual.

Check each vacuum connection in turn by disconnecting it and blocking off the port.

Memcal details https://elanchips.co.uk/index.php?optio ... &Itemid=11

Have you thought about going closed loop? that would solve it.

[dapinky]

Have you thought about going closed loop? that would solve it.

.......I am pleased that your CO readings are a lot better, and I would suggest that as you can get within the readings required for the MOT (albeit that it isn't on a VOSA callibrated machine), then a 9930 chip replacement will be money spent for little result...... however, money spent to replace the chip with a 1499 chip and adding an O2 sensor will mean that you'll never have to worry about the emissions again, as they'll be down to something in the region of 0.5%...... and at that point (if you're changing the chip anyway), then there is little (if any) cost difference in getting the Everest version of the 1499..... and then it's a whole new ballgame of fun!

Perhaps my post wasn't as clear as I had hoped, and the EPROM numbers I was quoting wern't understood - my suggestion was (basically) to go closed loop as it would save a load of hurt in the future...

[Chas54]

Thanks for the post guys.

I did think the closed loop option was a good idea but I couldn't see any existing wiring near the turbo for the electrical side of the O2 sensor , so I thought I would use what would be a straight replacement, I can do without the added power really.

Not only that, the car must have been at a reasonable CO when idling and hot in the past to comply with the DVLA regs, I thought I should be able to return it to the same level of tune. I don't want to introduce to many new variables until I am on top of what the original fault is.

The CO pot and the IAC screw have both been adjusted in the past by the look of them.

I will check the plumbing of the vacuum to the crankcase breather and I may even blank the vacuum side to test.

I should get a new serial to USB card from an ebay vendor tomorrow , I did think I was going to be smart and fit a dapinky switch in the lead between the card and the OBD plug. My OBD plug isn't fully populated though so I drilled into the side of it to solder a wire to the terminal next to the earth. I thought I would fit a switch there but the elan scan isn't working and the chip is no longer lighting up although I didn't get to try the new terminal. The cables are intact and continuos so I'm hoping its only the cheap card I used has failed.

I am hoping my problem now is I haven't managed to reset the IAC via a confident rest procedure.

Iam saving the closed loop as my last option .

Regards

Charlie

[dapinky]

......I did think the closed loop option was a good idea but I couldn't see any existing wiring near the turbo for the electrical side of the O2 sensor , so I thought I would use what would be a straight replacement, I can do without the added power really......

Charlie,

The wiring comes out from the OS wing (where the blue arrow is) - there should be 2 or 3 sets of wires here, one of which is the correct plug for the O2 sensor wiring.

There are a number of itterations of chip which will be 'closed loop' - you would be looking for a 1499 EPROM identifier (standard to UK S2s, and Fed cars - except Calli ones). A 'standard' 1499 will have no power increase over what you currently have, but will be mapped for an O2 input. It is only if you opt for a 'mountain' chip that the various power output curves are changed.

I would even suggest that there are probably a fair few 1499's sitting on owners' shelves from where they have upgraded to a mountain chip, so a S/H option could well exist.

I think I paid about £30 for the O2 sensor, and had the 8 open and 8 closed loop profiles put onto a single (16 position) selector chip.

I've (probably) also got my original 9930 chip somewhere if it's any use to you - but I'd need to have a root around to locate it.

[Chas54]

Thanks for the offer Dave but I ordered the 9930 from SJS (£85 with delivery) earlier this week and am expecting it forthwith.

Ive just put my rear caliper back on and whilst topping up for the bleeding, I had a quick look at the wiring again. I think that where you have pointed out on the inner wing there are two unused plugs , i think they are pushed into a blank retainer like the service OBD and it fooled me initially. That being the case , and ill make certain later, where would you put the O2 sensor ?. I cant spot it on your picture .

Simon suggested the crank breather contraption as a vacuum problem if incorrectly plumbed and I just pulled the vac side hoses off and didn't get a change of engine tone. Ill have to have a look at it I think .

But it will all have to wait as I seem to have let some air into the brake system somewhere other than my rebuilt calliper. Ill probably have to bleed all round despite using a pipe clamp and cling film over the reservoir.

I have been considering taking the inlet plenum off entirely for a clearer look at everything attached to it, but iam a bit daunted by the fact I cant see half the bolts .

regards
Charlie