himself

Good to know and less work for me, thx.

I didn't test whether or not the old water sensor was grounded to the block, seeing as the block is aluminum the ground would not be that effective and no other parts are grounded to the engine itself. Instead I took my therm housing to a friend who owns a drag shop and had him tap out a new hole for the GM sensor. Got a new gasket for the housing and will install it today. Thanks for all the info. In regards to the IAT, I had an unused factory-tapped hole on the 4th tube of my intake that the IAT fit perfectly into with no modifications so I put it there.

I saw in another post that the new LC-1 widebands do not need the resistor. How do I know which LC-1 I have? Mine came in a blue/black box with an orange horizontal lightning graphic on the cover.

I did not know that the water sensor could be gronded through the block. I'll check and find out, thx for the info.

I only have 2 tapped holes in the therm housing and 2 untapped ones. I plan to take it to a machinist tommorow and tap one of the larger untapped holes and fit the new sensor there. I'l plug one of the others with the old sensor but not hook it up and the third has my thermal sensor for my heat gauge so it will stay put. Just thought maybe there was a water temp sensor that fit perfectly that I missed or whatnot, guess they don't make 'em that small anymore.

I bought a new water temperature sensor to install in place of the old one since the old one had only 1 wire and I need 2 wires for the MS. The one I pulled out has smaller threads than the new one and is a bit shorter. Did I get the wrong one or am I going to have to drill out the original hole to make room for the new one?

Sac was more of a reference as to where I am since no one know where Latrobe is. I'm halfway between Sac and Placerville, Modesto is a very long drive for me but thank you for offering. Can you post some pictures of your engine though? Location o sensors and where you ran the wires would be great to see. ZR8ED I'm not sure which year engine you have but I did find on the '82 zxt I have there is a vacuum control sensor located in the 4rth intake tube from the front of the engine. You will have to use a metal saw or grinder to cut off the top of the sensor to get to the bolt so you can unscrew it but the IAT sensor fits in its place perfectly. That way you don't have to drill a new hole.

Thx Matt, that was what I needed to know. I will remove the old transistor and run the coil directly to MS.

I have read that post, printed it even and know which wires go to the MS and the 12v. The only difference is that my coil does not run by itself, it has a stock power transistor as mentioned in the wiring schems of the manual. If take the transistor out the spark is not powerful enough to start the engine. Here is the wiring schem from the manual for the coil. What I would like to know is do I run a negative lead from the coil to the MS unit or from the transistor to the MS unit? Or do I not even need the transistor anymore b/c of MS? Sorry for being counterproductive there Naviathan, I thought you were talking about using MSnS which I do not have the code for, I have just a standard MS 3.0.

Back to the IAT sensor, at the top of the manifold there is a vacuum controller that looks about the same thread type and size of the IAT, can i remove it and put the IAT in its place?

Thx for the reply, that IAT sensor part was very helpful. I got a 240sx tps switch as advised by the DIY guys and it has the standard 3 pole plug in the top but also another 3 wires coming out of the witch to another plug. Took a couple hours but after research found out that they both do essentially the same thing but one is far more precise than the other and used that one. I was able to reuse the 280zx TB and rig up a way to mount the 240sx tps so that I do not have to replace the manifold intake or adapt the 240sx TB onto the manfold. Was rather simple, just wish I'd had the idea cross my mind 6 hours ago. Does the map sensor have a spot already setup to plug in or will I have to make one like the IAT sensor? Now that I think about it did I get a map sensor with the MS or did the car already have one? I do not remember seeing it in the packaging.

Actual I was wrong, i am connecting ms to the distributor, so it will control my spark. I originally had to add the power transistior because the 82 turbo distributor would not send spark to the plugs. i am afraid to connect he MS to the transistor, should go ahead and connect pin 36 from MS to neg side of the coil anyway?

No the timing will not be controlled by the MS. I had to add the transisitor just to get the coil to spark, it was so weak without it the motor would not run.

This MS system has me frustrated, nothing is making sense with the wiring. Why did I have to buy a 6 wire tps switch and it only tells me to use 3 wires? Now that my ecu is out what controls my gauges, my starter, and other things the MS doesn't, where does the air intake sensor go? What else has to be removed to get the rest of this stuff in place besides the old TB, all the vaccuum lines, the air regulator, and how to do plug it all up? I know this thing isn't plug and play but the hardware modifications to the engine alone are going to take me weeks to complete, custom manifold, TB adapter, custom air intake line, plugging vaccuum lines, plugging coolant lines and all this before I can get to the wiring. This is the MS system I purchased: MS130-C $330 Assembled Megasquirt-I with V3.0 PCB MOD_130IGBT1: Single Ignition Output through IGBT (VB921) $20 MSHarness $65 12' wiring harness IATwPiggy $21 IAT Sensor 38NPT-Bung_S $8 Bung for mounting IAT sensor (steel weld on, or JB-Weld on) TuneCable $6 6' DB9 tuning cable USB-2920 $20 (Only needed if your laptop doesn’t have a true DB9 port) WB-LC1-3769 $199 Innovate LC-1 system I have a 1975 280z with a completely stock '82 280zx turbo motor. I started this project only to get rid of the AFM since I go through one AFM every year. They burn out way to fast to keep replacing them. There must be something I'm either not seeing or doing wrong because this is taking far, far longer than anyone else has done it in and I haven't plugged a single wire in yet. Would it have been best just to get the SDS system since with all these new modifications I've spent more on the MS than the SDS system would've cost me in both time and money? Is there anyone in the Sacramento area who can take a quick look one weekend or another and point out where to start and go from there?

I have a power transistor hooked up to my coil (page EL 32 of the 1982 manual) and am not sure how to hook up the MS unit through it. Anyone done this before?

I've hit another wall as well. I had asked before if the MS unit replaces the ECU and was told it does but my gauges all run through the ECU where as on the MS diagram they have no wires going to the gauges. Am I going to have to use both the MS and the ECU units?

Thank you for the explanations. Another question though, I was notified I would need a new tps switch and that a new model nissan 240sx' switch would be interchangable for the 280zx's and cost less from a junkyard. I got the switch and it slides in place but the mounting bracket on the 240sx is smaller than the 280zx's bracket. For those that did this mod, how did you mount it? 280zx on the left, 240sx on the right. Notice the width of the mounting plate.

Thx for the pm spacecase70, just noticed it. If I get into a real bind I may give you a call. Another question about the wiring though; on the diagram it has listed that the IAC has 4 wires and the dizzy only 2 but upon pulling the old harness off the car the dizzy has 4 and looks a lot like the IAC in the diagram. Any help here?

found the relays, though not made by bosch, they have the required numbers.

Ah ok, I did not know they worked that way, thank you. I did find out what the rekays they mention are expect that they are no longer in production. So do the bosch replacements also have the same set of 4 numbers listed on each connection to match what the schems say? Have a part number to go with them as well?

I've already read this one which was not much help. I do not have a relay board, am not using any GM parts and do not have the MSnS version. On the wiring schematics I have been shipped they have 2 wires controlling all 6 injectors which makes no sense to me; how can each wire tell which injector to fire if it is talking to 3 at the same time? I've figured that the numbers on ther relays are actually embossed on the relay itself where the connections are made but they do not tell me what type and manufacturer the relays are. Mine do not correspond to their schems, anyone know which they are talking about? Ignore the arrows question, it is supposed to mean adding more injectors. It is a one type fits all schematic which sux.

I'm sure someone has posted the info but I cannot find it about what this wiring schematic I got with the megasquirt means. I've got a '75 280z with an '82 zxt motor in it and just bought the ms1 with the lc-1 and 12' wiring harness from diyautotune.com but the wiring schematic they give with the kit is not like any schematic I've ever seen. Can anyone explain it it detail? Where do the last 2 injectors hook up? what do the numbers on the relays mean? where do the arrows on the injector wires go to? Anyone have a really good link for installing the ms on 82 zxt stock engines?

I did search the forums as mentioned above but I was unable to find any links as useful as Warren's reply. Thx Warren.

I just got a 240sx throttle body w/tps switch to add to my 82 zxt b/c it was much cheaper than getting a tps switch for the stock zxt tb. The 240sx tb is slightly larger than the inlet for the zxt and I know a lot of guys have done this modification but I cannot find the info here of where to get an adapter to make the tb fit correctly. I searched around for a while and found a lot of info about the sx tb but nothing about installing it on zxt engines.

ahh, sry. Saw 90mm and accociated it with the wrong one. thx for the correction.