Intermitent spark on ! & 3

[dapinky]

Thanks for the info on the D7 pin. I don't actually have a copy of the closed loop manual . I was given a disc with the manuals on when I bought the car but the ECU part has no amendments for the later closed loop system.

Charlie,

The Closed Loop Manual is available to view or download from the 'Manuals' tab at the top of this (or any other) page once you are logged into the forum

[Chas54]

Thanks for the O2 sensor wiring diagram. It will be usefull. D7 isn't wired on my ECU plugs but its there.

Thanks dapinky, I hadn't spotted that the manuals were in the literature section. Obvious really ,but I thought it was full of sales brochures, its a revelation!

So once I get everything up and running , I can see where the O2 is wired to - I have the plug under the bonnet and its wired to the above driver footwell plug, but no further . I will probably cut the cable and joint to some new wiring. Ill have to identify the alternator field supply cable as well , but I should be ok with that.

I will have to look for the upgraded memcal unit , the 02 sensors look to be available and then I will attack the blower with the hot blue spanner.

charlie

[GeoffSmith]

Not sure how you're planning to test them but probably best not to a connect them directly to a battery - the coil saturates in a few 10s of milliseconds & can burn out and they can generate 100s of volts when disconnected.
https://www.underhoodservice.com/fuel-i ... waveforms/

[Chas54]

The ebay fuel line pressure tester arrived today. I had to use some bits and pieces I had to couple up the T piece but got there in the end.

The delivery pressure is around 43psi and with 15"hg vacuum pulled on the fuel reg actuator, I get a drop to 35psi.

The manual states a 50kpa vacuum should produce at least a 15kpa fuel pressure drop , 15kpa is around 2.18 psi . So fuel reg seems within spec.

The injector test wasn't electrical at the moment , although I did check resistance all at 2.3ohms. The test involved suspending the injectors on the rail over a drip tray sat on the cam cover , and leaving the fuel system primed at 40 psi. The pressure holds well, as I walked away and left it (ignition off of course) . There is evidence of a drip on No3 injector and at one stage thought No.2 as well . Im leaving it overnight to prove .

I had these injectors cleaned and balanced in November 2019 and I haven't done many miles since then. The resistance then was noted as 3.4 ohms .

I'm wondering if I should try some inject cleaning gunk or just get new. The cars done 75k miles .

Charlie

[Chas54]

Thanks Geoff.

I had a quick look round you tube for people cleaning injectors at home. I found an American using a syringe full of carb cleaner and splashing a 4.5 volt battery on one terminal . Its not dead accurate at all but it does allow a flushing through of the injector with cleaner.

I've tried it and i think i will fit the injectors back in the rail. On a drip tray sat on the engine top, then pressurise the system and see if i still get a drip.

Looking at injector prices horrified me a bit but i found some on ebay from Florida . elinjector or something he trades as. Claim is they are original Delphi? .

I may risk the investment.

On another note, i was wondering if anyone knew what the threads are on the fuel recirc line, at the junction behind the engine . I thought the inlet line was 1/4" BSP but now its off the car , its close but not exactly that size . My recirc line seems to have been joined there at sometime with a piece of flexible pipe and a pair of jubilee clips. Been there a long time i think but its the grottiest piece of fuel pipe i've seen for years.

Thanks for any suggestions
Charlie

[Simon_P]

Claim is they are original Delphi?

Better than that - Claims they are original Lotus - In either case they will have the OEM part number on them and have the correct 2 Ohm spec (see the manual for the injector spec.) Both conspicuously absent from the eBay ad. I would check with the seller before parting with any cash and make sure you are covered by ebay buyer protection.

The low resistance is to do with making them open fast which requires more power. At 14v the power required is 2 Ohms / 98 W. by comparison 7 Ohms / 28 W and 14 Ohms / 14 W.

[Chas54]

I will ask if these are genuine and make sure the ebay/paypal protection is there , although I think the paypal bit is soon to finnish. The price does look too good to be true.

Having blasted cleaner through the injectors and refitting onto the fuel rail balanced in a drip tray on top of the engine, I found last night the reg valve would no longer stay shut. I haven't done anything to it , not even washed it out with carb cleaner . So took it off and tested it on the bench , the vacuum actuator is no longer holding a vacuum and leaks away gradually over 3 or 4 seconds. Surprisingly the valve seems shut on the bench , which makes no sense to me . It also doesn't open at all under 20"hg although I cant maintain that vacuum now the diaphragm has failed .

The result is i've ordered a new reg valve at the horrendous price of £112. from SJS .

I going to cut this reg valve open and see if I can make any sense of it. I suspected this reg valve was sticking shut or very slow before commencing my investigation , but it initially tested within the spec in the manual, when I had the assembly balanced on top of the engine two days ago. The diaphragm held vacuum and there was no decay.

Thanks for the injector resistance figures.

Charlie

[Simon_P]

I think the FPR works on differential pressure ie you need the fuel pressure to load it up against a spring, then the manifold pressure provides a pressure differential which closes or opens the valve to adjust the fuel pressure under vacuum or boost. The idea being that the fuel pressure increases/ decreases with the manifold pressure.

If you think it is suspect this could easily be the cause of your rich mixture. ie by not reducing fuel pressure more than the desired fuel quantity will be delivered.

At £112 I hope an new FPR is the cure! I've not really considered this before as the O2 sensor would compensate please let us know how you get on and it would be interesting to see pictures of the FPR dissection.

[Chas54]

I think you may be right about it operating with the fuel pressure assistance but. The day before , the fuel pressure with both inlet and outlet lines attached to the fuel rail, reached 43psi and held there without any decay over a couple of minutes. With the reg then having the required 50kpa vacuum the pressure dropped to 35psi , and would stay there . The vacuum holding reasonably steady.

Today the vacuum was decaying within about 20 seconds but even without the vacuum, the fuel rail struggled to reach 30psi. The hoses aren't kinked or restricted , fuel filter new last year.
I took the reg valve off and it refused to hold vacuum in the actuator still , and blowing though it didn't pass. with an airline on the reg inlet , at 30 psi it will pass some air .
Its odd as when it was on the car I uncoupled the return line and let the reg valve relieve itself into my drip tray. Even with no vacuum it passed virtually full bore at the pump pressure bellow 30psi..

I don't think it can be a return line blockage as the inlet pressure wasn't achieving the previous day 43psi when the return pipe was joined.

Its just like it was jammed open , but now jammed shut.

When I get the new on and have it working I will carry out a post mortem and post the pictures.

Think I might follow the return line all the way back to the tank though, having written this, its raised a suspicion it may be kinked elsewhere .

Iam currently a bit sore having spent the day laying on a floor pad on top of the engine cleaning off the well bonded but damaged inlet manifold to head joint.

Regards
Charlie

[Chas54]

New fuel pressure reg valve arrived and is now tested . Only issue is the centre upright vacuum hose connector but I see the answer is drilling the engine lifting eye bracket. It seems to control the inlet pressure at around 37psi without any vacuum and under 15" hg vacuum , drops by more than 3psi. None of the injectors now pass after the flush out with carb cleaner. This is lower than the old reg but still in spec and may help with the high CO.


I've ordered the injectors . I figure ill keep them for future use .

Whilst cleaning everything up I had easy access to the alternator connections and managed to ring the field winding supply cable through the wiring to the O2 sensor wing plug , That just leaves the slate grey with green band wire to find at the ECM. Its a bit tricky to separate the wires at the plug and identify which one is the D7.

The grotty piece of petrol pipe on the fuel return line may have been the original . I see in the manual it is described . I've replaced it with some 8mm I.D. modern 'rubber' petrol line.

Hopefully I will have some new gaskets arriving tomorrow .

Charlie

[Chas54]

Got the car mostly back together. New fuel reg valve fitted . all joints replaced and thorough inspection of plenum and inlet manifold. I took it off to check out the secondary throttle and figure out how the idle air works, and inspect its valve seat.

It all looks good. Lost one injector cable plug securing clip but found the instruction for making one from a paperclip.
Checked timing when engine running in service mode but I couldn’t achieve a low enough idle speed without having the idle air screw nearly all the way in.

I contacted Gunson about my timing strobe problem and they replied that my strobe wasn’t compatible with a waste spark system but they had one at £250 that had a mode selection switch to allow for this. Also the missing spark that wasn’t really missing, could be a result of this interference.
I think I will make do with the one I have and just ignore the problem and since I now use number 4 cylinder, it looks a lot better – no waste spark and no missing actual spark..

I found I still couldn’t get the CO bellow 7% . the CO pot adjustment is at the very end of its range (screwing out) .

I also found the heater valve failed during my test . I must have disturbed it and its rusted through on the water side. I’ve inserted a piece of copper pipe in the sghort term but have received a Volvo 70 one from ebay at around £20 .

I have acquired the O2 sensor and the new ECU for the closed loop conversion.
The D7 pin is cabled up from the ECU plug to the internal wing plug.

Ive been spraying plusgas on the turbo plug for days and with the engine hot I thought I might try removing the plug . I do have some 18mm spark plug inserts for Austin seven aluminium heads , so I thought if the thread strips I could fit one.

The turbo plug came out leaving a good thread in the casing but the plug thread not so good. Anyway O2 probe in , ECU swapped , start up and immediately CO at 2%., Idle air screw backed out around 1.5 turns.

I notice the that the injector pulse width is lower than I could achieve with the CO pot adjustment. Now that’s redundant I’m guessing the O2 processing alters the injectors period.

I have a few bits left to do but hope to go out for an ECU/idle air learning run in the next few days .

With a bit of luck I have posted two Elanscan data sets, The first isn’t very representative until the last period, I was adjusting the timing , fixing the coolant leak and adjusting the CO pot with the 9930 ECU.

The second set is with the 1499 ECU.

30th apr 21 fuel reg swap 9930.zip

Got the car mostly back together. New fuel reg valve fitted . all joints replaced and thorough inspection of plenum and inlet manifold. I took it off to check out the secondary throttle and figure out how the idle air works, and inspect its valve seat.

It all looks good. Lost one injector cable plug securing clip but found the instruction for making one from a paperclip.
Checked timing when engine running in service mode but I couldn’t achieve a low enough idle speed without having the idle air screw nearly all the way in.

I contacted Gunson about my timing strobe problem and they replied that my strobe wasn’t compatible with a waste spark system but they had one at £250 that had a mode selection switch to allow for this. Also the missing spark that wasn’t really missing, could be a result of this interference.
I think I will make do with the one I have and just ignore the problem and since I now use number 4 cylinder, it looks a lot better – no waste spark and no missing actual spark..

I found I still couldn’t get the CO bellow 7% . the CO pot adjustment is at the very end of its range (screwing out) .

I also found the heater valve failed during my test . I must have disturbed it and its rusted through on the water side. I’ve inserted a piece of copper pipe in the sghort term but have received a Volvo 70 one from ebay at around £20 .

I have acquired the O2 sensor and the new ECU for the closed loop conversion.
The D7 pin is cabled up from the ECU plug to the internal wing plug.

Ive been spraying plusgas on the turbo plug for days and with the engine hot I thought I might try removing the plug . I do have some 18mm spark plug inserts for Austin seven aluminium heads , so I thought if the thread strips I could fit one.

The turbo plug came out leaving a good thread in the casing but the plug thread not so good. Anyway O2 probe in , ECU swapped , start up and immediately CO at 2%., Idle air screw backed out around 1.5 turns.

I notice the that the injector pulse width is lower than I could achieve with the CO pot adjustment. Now that’s redundant I’m guessing the O2 processing alters the injectors period.

I have a few bits left to do but hope to go out for an ECU/idle air learning run in the next few days .

With a bit of luck I have posted two Elanscan data sets, The first isn’t very representative until the last period, I was adjusting the timing , fixing the coolant leak and adjusting the CO pot with the 9930 ECU.

The second set is with the 1499 ECU.

30th apr 21 fuel reg swap 9930.zip

30th april 21 final 1499 ecu.zip

Fuel pressure reg post mortem revealed a small split where the diaphragm joins the central metal insert there was also a couple of bits are dark carbon material in there as well. Hopefully I can attach a photo. No petrol found in the vacuum side.

Fuel reg.JPG

Charlie

[lotusflasherman]

I don't actually have a copy of the closed loop manual .

Charlie

Edit : Think I've duplicated an earlier answer but I'll leave this here, in case others have missed it ..

Look up at the LEC Header ... 5th from left is Manuals, Click ... 3rd down in Left Column is Closed Loop Manual in .pdf form.. Click ... Now you do!

[dapinky]

Charlie,

You certainly have progress, well done.

One thing that I notice is that you say you are still getting about 2% CO2....... whilst this is easily low enough to pass the MOT, mine came in at 0.61 this week on the MOT test, so I don't know if you still have an issue somewhere, or if it will gradually drop with use as the engine gets used to running closed loop and cleaning out crap from the exhaust???

[Chas54]

Thanks, found the manuals OK now.

I think the suggestion that the 2% CO might be some residual affect is a real possibility. Over the past month the car has spent most of its engine running time in my garage idling, and hot enough for the fans to cycle.

Maximum plenum vacuum then, with the engine vent breathing oil vapour into the plenum . Both ends of the plenum showing signs of some oiling when I had it off.

I think a sound thrashing may be in order- after the obligatory 30mph relearning run of course.

Thanks for all advice and suggestions

Charlie

[Chas54]

I haven't had a chance to try out the Elan since doing all the work but I post here a couple of pics of the injectors I received today from the US ebay.

There is an RP logo embossed on the plastic and the numbers on the injectors say
2112 17113749.

The fuel rail retainer clip looks a little different but I don't think that would be an issue.

They were not in any marked packaging , just bubble wrapped.



Due for some sun tomorrow so I may well try the Elan and if the CO looks good I will probably put these into spares cupboard.

[Chas54]

Cant seem to attach picture - to large possibly.

Anyway I should have said , cost of 4 injectors with postage and customs was £194.46.

[Chas54]

lotus new injector.JPG

Injectors

[Chas54]

I have just had my first real run in the Elan since changing to closed loop .
Bit of a delay but other events have overtaken me
A test after swapping the ECU and installing O2 sensor a month or so ago alarmed me when about half a mile from starting, the ECU light came on for a couple of seconds and 20000 faults instantly achieved.
Today after clearing all it didn't happen though .
It doesn't seem to be running as rich but it isn't as good as I had hoped. I have dropped my Gunsons exhaust gas tester and it has failed to read anything other than 2% now. Today at the MOT test it was at 4.25% after a run.
I had reset the IAC learnt position as seen on my elanscan trace attached at 1200 seconds. Having said that, I can see that when idling the IAC gradually closes in to the 2 count position . I don't understand this because the revs aren't changing and the improving manifold vacuum would indicate I don't have significant air ingress through a leak. The IAC at position 2 counts would seem to indicate air ingress somewhere.

If anyone can spot something I am missing I would be grateful

Charlie

first run new ecu to hilltop29jul21.zip

[Simon_P]

I had reset the IAC learnt position as seen on my elanscan trace attached at 1200 seconds.

That doesn't make sense to me - it looks to me like you hit 30 mph and it did its own check. The only thing you should do is set the idle exactly as described in the wiki.

Your O2 sensor doesn't look right - (with gracious thanks to Mr Smith) the voltage trace should look like the last post here
viewtopic.php?f=38&t=28362&p=363765&hilit=sensor#p363765

[Chas54]

Simon
thanks for comments.
I can see from the scan you sent that on the new O2 sensor your idling voltage is 2v.
Mine looks like it was 2v initially but after the the first run with the automatic reset of the IAC (I had disconnected the battery before the run) , my idling voltage is 4v. Looking in the manual I see this indicates a rich state. So I think the O2 sensor is reading correctly, it smell a little rich at the exhaust.
I thought I had been adjusting the idle speed correctly but you've prompted me to go back and recheck it so I am going to go back to recheck the base line timing with the engine warmed and in service mode and the IAC confirmed at 20 counts. Then adjust the idle control screw to 950 revs , recheck the baseline timing and then exit the service mode. Then hopefully give it a run.

It does seem to be odd that on my traces the IAC closes to 2 counts but the plenum vacuum is good at idle speed . With the exhaust appearing rich at the same time, I would expect the IAC to open and allow more air in ?. I can only think i've set it wrong in the first place.

Thanks again for your advice .

regards
Charlie