quattro

They all work Garry , but the one you have put up is of an unknown quantity, the others are from the Megasquirt manual. I will try it if all else fails, so thank you for posting it There does appear however, to be something wrong with the feed wire from the ECU, so I really have to find out what it is and fix it, as I don't want to bring my car home one day in a box donated by the fire brigade. My problem is that I bought the system from supplier A, who was so difficult to get hold of, and then when I did, didn't have an answer so I found another supplier from another forum to buy a tachfix box. So, supplier B didn't sell the tachfix box and put me onto supplier C who I did a load of testing for, then bought the box, and it didn't work. C then added a wire to the ECU which would gaurantee that the tacho would work - it didn't. Then work and life got in the way and I just the car back on the road with a tacho bouncing about like a demented grasshopper. Now, I have the car off the road again and have contacted C who said, "hmmm that's strange," and now doesn't answer emails. I asked supplier B if he could look at the ECU to check it's connected ok, and he has refused, saying that I should go back to A or C. So, my options are 1/. Keep pestering you chaps 2/. Find supplier D 3/. Go the uni and become an electronics expert 4/. Put up with not having a tacho 5/. Remove the wire myself and make up some fixes and try them all out on at a time - hoping nothing burny happens. 6/. Get a 14CUX and admit defeat

As I already had the wiring for the tachfix, I have made up the board as per Quagmire's diagram. It can be made up to just plug in to the same wiring so much easier and neater then trying to splice into the coil pack wiring. Nothing, tacho doesn't even flicker. As the tachfix doesn't work, and this set up doesn't either, I really do have to suspect the wire added to the ECU. Tapping into the coil packs does work albeit only up to 1,300rpm, but there is something there. Is there anyone on here that can check out the ECU for me? Cheers Richard

D'oh!

So, I removed the Zener and replaced it with a 1K resistor, now it doesn't work at all For complicated reasons I can only make the box of tricks up at home, then go to the car and fit it, making it difficult to actually adjust it when fitting, so I have decided to buy a few bits and pieces in and make up a few different types to try. They're not really expensive and it does give me extra confidence in building these things @Quagmireis it obvious which way to connect that 2N5551?, does it matter what wattage the 1K resistor is, and do I take it that 0V means earth? I have googled the 4 x 1N4004 fix and found that it does indeed have problems, with someone saying his car ran like a bag of nails, some only starting to show RPM at 1,500, and others only showing up to 3,000, etc There are various ways to fix this and I'll be giving them a go as well. When attaching the four coil wires to the -ve side of the coil, does it matter if it's right up close to the coils, or can it be hidden away at the other end of the wire, close to the EDIS? Why is nothing ever easy

Hi Jamie, yes I realise that as I remember you using the relay in your build. I am not good at electronics, in fact this is the first time I have ever soldered anything into a board, so I wasn't confident enough to go into the ECU and add a tach feed wire. I sent it off to get it done from the same person who supplied the tachfix. As this didn't work, I don't know if I can trust the feed wire, so had to take the fourth option and take feeds from the coils. This system obviously works as the tacho is smooth right up the 1,300rpm:) which is 36mph in top, but it just breaks down above that. I have found this on a google search last night so might have a try at it:- ".......... you can try removing the zener and replacing it with a resistor of between 330R and 1K, the zener is not actually there to limit voltage to 18V, it is there to block the 12V present at steady state. Further, the IN4004 diodes will not really conduct well into an open circuit (which you effectively have with the zener there). An alternatve approach would mean adding a resistor of between 1 and 10K after the IN4004 diodes to ground BEFORE the zener, this will allow current to flow through the IN4004's properly and should allow the zener to break down as you expect." What could possibly go wrong ?

I don't have another vehicle, but I do have a 4 cylinder tacho. I tried this on my car with the tachfix and it did exactly the same as the 8 cylinder one, i.e. just bounced around. I haven't tried it yet with my made up box of tricks, but I will do shortly.

Video of tacho behaviour Tacho 1300.mp4

Right, I got one of these, a box to put it in and chopped it to size. Then I purchased 4 x 1N4004 diodes and a 1N5355B Zener Diode and popped them in Soldered them all in And then connected the brown (plus tracer) wires to their respective colours on the wires to the coilpacks. Then the Zener to the tacho. Start the car and the tacho works, sittting there stable pointing ta 800 rpm which according to tunerstudio is correct Slowly increase the revs and the needly rises following tunerstudio, so excellent - UNTIL it reached 1,300 rpm when the needle just drops. So, I have The voltage from the purple/white wire to the tacho is around 7V on tickover, but goes up when the engine is revved, if that's any help? Have I done something wrong here? I have copied the diagram in Quagmire's link exactly

Thanks to both of you I am however not brilliant at electronics. I can follow and make wiring looms, which I have done of course, but really not sure about making up these circuits. If all else fails though, I will try the 4 x 1N4004s in Quagmire's post. As I have a wire fitted to the ECU as a tacho output, a tachfix, and a Tacho which 1/. Worked with the coil set up, and 2/. a spare Tacho I have does the same and jumps, I can only assume that something is wrong with either the output wire or the tachfix. I was hoping that there is something in Tunerstudio was pointing in the wrong direction and that I could just hit a few keys and get it to work - now there's optimism for you Is there any way, with the help of a multi meter that I can check the output wire and the tachfix? I have done some basic testing - does this lot look right? Ignition off, I checked from the wire at one side of the connectors to the wire at the other side, to check for any resistance. None at all for any of them, so connectors are ok. Resistance from yellow wire on Tachfix to back of tacho - 0.04 ohms. Black wire on tachfix to chassis - 0.04 ohms. With the ignition on, all connected: - Red 12.58V Orange 0.81V Tachfix to ECU Yellow 0.04V Tachfix to tacho Black 0V Engine running Orange 0.06 to 0.13V Yellow 13.6 to 14V Richard

Hi all, Most things working now and the car takes off like a scalded cat, drives nicely, starts well, etc. very please with the transformation from the four barrel Two problems still though, 1/. a bit of hunting now and then, which I'm sure I will chase down and sort completely very soon, and 2/. The Tacho - now that is driving me nuts Very long story, but I'll keep it as short as I can. End of 2016 I contacted a company who sells a device called a 'tachfix.' After conducting a few tests, like attaching the IDM to the tacho, where it made the tacho jump a little when engine turned on, and again when it turned off, nothing when running. I then disconnected the orange wire on the EDIS and brushed it against a ground with the ignition on, and the tacho jumped to 500 - 1,00rpm every time I did it. I then connected the SAW to the tacho and that worked but was reading 100rpm low, not a problem, that would do. He gave me two options, the one I chose was to send him the ECU and he fitted a tacho output, which connected up to the Tachfix. It arrived back and I connected it up, red to ignition live, black to earth, orange to new tacho output wire and yellow to tacho. Fired the car up, the tacho burst into life but the needle just bounced up and down. I have uploaded a video of the tacho with the tuner studio one next to it. The only other thing, which may or may not be connected is a strange reading from the "Rear bank O2 voltage," which shows the needle pinned to the end of the gauge, as in the pic attached. The car is ticking over when this is happening. I was just wondering if, somehow the output for the tacho is pointing at the O2 gauge instead? I don't know how or why, just guessing. Any ideas anyone? Richard Tacho.mp4

I do like to complete threads Nothing worse than searching on a forum for an answer to a problem, then reading four pages of thread, to get to the end of it and still not find out if it worked Finished it off this morning and have been driving around Thanks for the help

Sure was - cheers for that Got one of these with two female 1/8 npt, and one male 1/8 npt threads. Got it fitted in just the right place and screwed in a pressure sender Refitted the valve, and a bit of wiring later, just need to refit the gauge pod and dash. And yes, it works Richard

Brilliant, thanks Bowie I'll give that go Cheers Richard

D'oh! Yes, I have the schrader valve, not quite sure how I would connect that up though. What's the usual way of installing a fuel pressure gauge? Richard

This may sound a daft question, but I don't know the answer so thought I should ask Can I just remove the fuel temperature sender, and screw in a fuel pressure sender instead? If so, does anyone know what the thread size is? Richard

Just to finish this off Have sent the ECUo ff to get a tacho pin fitted, and bought a tachfix, but still not working fully. I'll get it one day. no doubt. I did nip it out to John Sleath who apparently knows MS well, as well as 4 barrel webers. He had a little play on the rolling road, but couldn't really improve it much, so very happy with what I managed. I did get what should be a final power run, and I am very happy with that, especially that torque curve. Many thanks for all the help, what a job that was

I googled the part number and somehow found this thread - I must admit that I have it running without altering the idle screw as I didn't realise there was an adjuster under the plug by the throttle body. There is no mention of this anywhere in the tuning manuals, although adjusting the throttle stop is mentioned a few times but I don't appear have one of those. I only found this air bleed while googling something or other about a week ago. Testing was going to happen today, but other things got in the way, so it will be tomorrow. Before doing this, I wanted to get some information about the PWM as I have read that the PWM valve is closed when 3.5V is applied to it. It is open when no voltage is applied and goes to default of fast idle. As open loop applies no voltage to it, it remains at fast idle. Hence my question, which was to clarify what to do about it. I have read that a base idle of 600rpm is good to start, is this about right?

Hi all Car is running quite well now (much better than it was with the weber) although in closed loop it does hunt a bit sometimes. So, I tend to run in Open loop (Warm up only) but I can't find a way of closing the PWM, so only get a fast idle at around 1,100 rpm. I have set the closed(dc) to 25 which should close it, but this is greyed out in open loop mode so it goes back to default and stays open. Data logging shows the idleDC at 0% at idle. Am I missing something here, or do I have to run in closed loop to get an idle at 800rpm? Richard

I am still learning, but my Spark Settings are different to yours. In 'Fixed angle' I have -10, so that it will work from the spark table. Then I used a strobe light to check the timing was correct compared to the reading on tunerstudio, then adjusted the 'Trim' until it matched. I have '1' in the trim angle as it was pretty much correct.

I got it now lads, cheers. I entered it as a PLX 0-5v (10-20:1 AFR) then I'll set the lambda to read 0-4v (10-18:1AFR). I hope I can do that . As they're both linear, they will both read the same up to 18. Then, mysteriously the AFR target table reverted to AFR I haven't tried it yet though.

S'ok - got it

A while ago, prior to fitting EFI, I had a 4 barrel weber, and to help to tune this, I fitted a 'Sack Wideband Lambda' which worked a gauge on the dash. I then fitted the EFI along with the supplied narrowband Lambda and got learning about the tuning side of things. It seems that the Wideband would be better than the Narrowband for tuning purposes so as I had some spare (perhaps too much ) time on my hands, I looked at the wiring of the Stack unit and found it had a blue wire which could go to the ECU or data logger. After a small amount of wiring the WB is now connected to the ECU. In the links above it says to set the switchpoint to 2.5V if using a 0-5V WB and after some googling I am basically told to set the 0-4v one to 2. 14.7 is 1.88v, hence the first question, 1.88 or 2? The links also say that as an option, you can set it to look at a target AFR table 8x8, where it would ignore the switch point. I want it to work from the 8x8 table, but just wanted to set the switchpoint correctly in case I had to revert to it. The AFR table on Tunerstudio is as the first box in the picture above, i.e 3.57 across the top rows (WOT) which is around 18AFR if my maths are correct, then lower rows it goes above the 4v to well over 20AFR. I tried to generate a table and TS did a reasonably good job by the look of it (second box in pic above) but when I clicked 'apply' I got an table with all 5s, and still in volts. Quagmire's link (Ta muchly) directs me to a thread showing me to go into the INI file of Tunerstudio (That's getting a little beyond me) and changing things in there. Is there no way to install the Stack WB without having to delve into the INI files? and how do I generate a proper AFR table for the lambda to work from? Richard

I've been reading this lot http://www.msextra.com/doc/ms1extra/MS_Extra_Software_Manual.htm#lambdaset and http://www.msextra.com/doc/ms1extra/MS_Extra_Tuning_Manual.htm#VESetts So, I'm aware what a wideband will do, but to use it as a narrowband, i.e. setting it at 1.88v at the switch point means I may as well use a narrowband. To use it as a wideband I need to set it to look at the 8x8 VE table 1. But, how do you tell the system what to look for? i.e. my WB will be giving 0 volts at 10 AFR, and 4V at 20 AFR, the ECU doesn't know this and I can't work out how to tell it. The drop down list doesn't have an option for the stack WB, or anything 0-4V. If I do go into the INI file and change things, then I have the next problem of the 8x8 VE table 1 reading in volts, and not AFR. I tried generating my own VE table using TS but when I clicked on "Apply VE targets for VE Table 1" I got all boxes saying 5.0. Anyone know how to load the stack WB, and how to get the target 8x8 table to read in AFR? Richard

hmmm... Thanks for the link. The stack WB isn't listed, and I don't really want to go delving into the INI files, so I think I'll just plug the NB back in for the time being. Also, the AFR targets for VE table 1, is in volts and most of it is above 4V . As 4V on the lambda is an AFR of 20, I can see the ECU trying to get the AFR to about 25! Hoping to get the car back on the road over the weekend.

I take it back, I'm just as confused I thought the 'EGO switch point' just told the ECU where AFR changed from lean to rich .i.e. stoichiometric mixture. Then the ECU (and tuner studio) used that voltage to correct the amount of fuel injected.