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Changed the design. You can test and then fit the bung so not taking fuel into cabin.


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@Markbcars
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Discussion Starter · #42 ·
Cheers!

As far as I know the ground is good, I believe the ECU earths to the engine, 2 wires going to the intake manifold.. Ground pin for triggering, would need to know where that is.

Cheers for the info on the gauge, I want something to test while trying to trouble shoot this problem but while researching, I found a company called Radium who make a fuel rail which can have a gauge stuck to one end of it, I like that and happy to keep the gauge in the bay. A lot of money just for a gauge but not really any other options which are as neat.

I'll get round to a compression test this weekend.
 

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layabout
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I want something to test while trying to trouble shoot this problem but while researching, I found a company called Radium who make a fuel rail which can have a gauge stuck to one end of it, I like that and happy to keep the gauge in the bay. A lot of money just for a gauge but not really any other options which are as neat.

or you can get different regulators and fit a gauge to them



Rich.
 

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@Markbcars
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Discussion Starter · #44 ·
Cheers again guys!
Willl look into the permanent gauge.

Compression test earlier, I have compression, all plugs removed, WOT, turned over for 5 sec

slightly varied readings from a stone cold turn over, battery starting to give up
Cylinder 1 - 4

216
183
161
209

not great on 2 and 3

unsure of where to go next here, is 2 and 3 my issue or can I move on to the fuel system?
 

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Happily expanding the To Do list since 1997
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The difference is a worry but none is low enough to prevent running. I recall the minimum spec of 125psi (for the original 1.6) but I can't remember the maximum difference allowed between cylinders. (Pretty sure your 216 and 161 psi results are a fair way outside it though.)
 

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@Markbcars
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Discussion Starter · #46 ·
I would still expect it to start, surprised by the compression numbers but I’m hoping that is down to not being run for a month and tappets in need of pressurising again (it’s always tappety after sitting for a few days) and oil coverage to cylinders etc. I’ll worry about that another time, has been running perfectly up till this.
 

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@Markbcars
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Discussion Starter · #47 ·
New pressure testing kit on order.. so I will plumb that in on the input line to the rail and test pressure while cranking and on key priming.

like the look of these radium fuel rails, they have a bolt on gauge too.


If my fuel pressure is ok, what next?! Pull cam cover and check timing up there?
fuel injector flow test?
 

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This probably isnt it, but as you said the spark looks weak, possibility a failing ignitor. - but im guessing the ignitor is part of the coil packs in a mk1?, and you have replaced them.. And if the ignitor failed you would get no spark at all..
If you are getting fuel, and spark, it must be a timing issue?
If you have checked mechanical timing? Both crank and valves, then it must be ignition timing? - have you checked ignition with a timing light?

I would guess at either cam sensor, crank sensor or ignition timing..

Just trying to be logical lol..
 

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Igniter/ignition amplifier is separate from the coils on a Mk1, it’s on the inner wing, drivers side.
 

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Happily expanding the To Do list since 1997
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Igniter is separate on the original 1.6 but right from the first 1.8 Mk.1s the igniter transistors are built into the coilpacks.
 

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@Markbcars
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Discussion Starter · #52 ·
Cheers again guys, however, got an update..

New NGK 7's plugs, I gapped them to .610 and fitted them over the weekend and that was that, didn't even attempt to turn it over.

Today, my fuel pressure test kit arrived, went out and plumbed it in, turned key and gauge went straight to 40psi.

Cranked over to see pressure during cranking and the thing fired up!! Total surprise and turned it off!
Quickly checked for any leaks in the test kit and went back for another crank and again, fired up and run perfectly, see vid's below. Tappety as expected but idling smooth and running on all 4, happy but confused, the only change has been the plugs between not working and now.

Removed pressure kit and all back to normal, fired up and now it's sounding like a Subaru, misfiring. Great!





Checked for leaks on fuel pipes, pushed in and wiggled all the HT leads, fiddled with wires, no change but then I noticed a mess around the exhaust manifold, WTF!!, switched off. Had a poke around, confused, worried... Logic is just telling me, misfiring on a cylinder so fuel is being blown through and that's what I'm seeing, obviously a shit gasket, not the first!





So, car is running but misfiring, it was running fine to start but it clearly developed, is an injector at fault and washing an injector out, dodgy leads, plugs.. Not sure yet

1 thing which is strange, this is with the previous coilpack and the new, on the metal bracket, 2 and 3 are etched into it, my car is running the plugs opposite to these, 2 etched mark goes to 3 and vice versa. Been like this for years and now across both coilpacks. I did switch the leads and the car still started but ran marginally rougher, longer to start. Switched back.

What now?! Send injectors for testing? I do hear them click when testing but now im worried one could be leaking..

Vids coming...
 

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@Markbcars
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Discussion Starter · #53 ·
Running, this was after starting it again after the first shock start.

continuation of that, running smooth, tapping but normal

The leaks



So maybe I need to run it briefly and then pull the plugs and see which cylinder is fuel ridden.

What is more confusing is why it is firing now! ffs
 

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Very strange.
So injector either stuck open or commanded open by ecu?
Do mtech do a ecu test? In the post or summit.

If the injector is permenantly stuck open then just applying voltage to the fuel pump would see which 1.
Im leaning towards ecu fault...youve been through everything else.

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@Markbcars
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Discussion Starter · #55 ·
I'm really hoping it's not the ECU, I will go crazy if so, a screwup with that before caused me to lose an engine.

I don't think it is however, I think my issue is an injector at the moment.

I plan to nip out and start the car and see if it misfires, if so, I'll shut it off, remove plugs, check if one is obviously wet, if not, I'll trigger to fuel pump to run and try and see if any are spraying. I do have control of each injector and during my tests, I could hear each one clicking, so I assumed they are opening and closing fine but perhaps not.

I do have some 501 bulb holders, I'm half tempted to wire each injector with a bulb and watch what happens during idle..
 

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I'm really hoping it's not the ECU, I will go crazy if so, a screwup with that before caused me to lose an engine.

I don't think it is however, I think my issue is an injector at the moment.

I plan to nip out and start the car and see if it misfires, if so, I'll shut it off, remove plugs, check if one is obviously wet, if not, I'll trigger to fuel pump to run and try and see if any are spraying. I do have control of each injector and during my tests, I could hear each one clicking, so I assumed they are opening and closing fine but perhaps not.

I do have some 501 bulb holders, I'm half tempted to wire each injector with a bulb and watch what happens during idle..
I thought id better just mention, that when i was deciding what ecu to go for (either me221 or ms3mini), i called up my local tuners and spoke to them about what one they prefer to tune or have the most experience with. One of the things that they mentioned (im going back about a year now) was that the me221's were giving them problems with a strange intermmittant misfire. Unfortunately i dont have any more details than that, other than i think it was something to do with the current firmware, so they thought. Maybe worth checking you have the latest firmware version? That was enough to sway me towards the ms3 mini.. They guys are hybrid tune in suffolk, they have a good reputation.. Just a thought...
 

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Good luck. I think youll find the 501 will just glow due to the high frequency of firing.
Should be able to test fire each injector in the meite software?
Seemed like a big leak of fuel too so have hosepipe primed and ready.
Id be inclined to run fuel pump first to check all shut. And if memory correct then fuel inj should be set to inverted in settings. Fingers crossed.

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@Markbcars
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Discussion Starter · #58 ·
I’ve done around 8-10k miles or so over 4 years with this entire setup so I’d hope it’s all solid really, I purposely avoid doing firmware updates to the ECU as that’s what killed my last engine.
ECU had a fault and was exchanged for another but with newer firmware, what I wasn’t told was that the timing table was now additive, so my timing was advancing itself as the revs went up. That led to detonation and kaboom for me. That’s in the past now and took it on the chin.
Unless my ECU has developed a fault over the 2 days it was parked on my drive, I’m trying to avoid pointing the finger at that until I check the injectors over, my gut is with those being the issue atm. The car has literally run perfectly up till now.
 

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@Markbcars
Eunos Turbo
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Discussion Starter · #60 ·
Good luck. I think youll find the 501 will just glow due to the high frequency of firing.
Should be able to test fire each injector in the meite software?
Seemed like a big leak of fuel too so have hosepipe primed and ready.
Id be inclined to run fuel pump first to check all shut. And if memory correct then fuel inj should be set to inverted in settings. Fingers crossed.

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Good point on the bulb and trying fuel pump first, I’ve got some LED’s so I’ll give one a try to see what happens.

cheers
 
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