510 L20B EFI conversion - the project is finished!

[LenRobertson]

I don't know if it would help you any, but I have an '81 200SX factory shop manual I can loan you. It goes into detail on how most of the components in the FI system work, good wiring diagrams, troubleshooting guide, testing procedure for the electrical bits, etc. However this is for the system with oxygen sensor, so there may be differences between your non-O sensor setup and what is in this book. The differences may be obvious, but might be wiring color changes or a few minor things to just be really confusing. It shows things like dropping resistors for the injectors, the relays and how they wire together, a bunch of stuff like that that you may need in your system.

 

I have to be in Spokane for a dentist appointment on Thursday, the 24th. I can drop it off at the store if you are working in Airway Heights, or your house, or whatever works.

 

Len

[Unclejesse88]

I'm not sure you two are talking about the same thing. In the picture above, the AIS is simply a fast idle valve for all intents. One side is connected to the intake before the throttle body, and the other is connected after the throttle body. The electrical connection is a heater. When cold, the valve opens and bypasses air around the throttle, raising the rpms. Once the heater warms up the valve, (think electric choke), the valve closes. The vehicle then runs standard idle rpm based on throttle body idle screw and Air Flow Meter idle screw settings.

[Sealik]

I'm not sure you two are talking about the same thing. In the picture above, the AIS is simply a fast idle valve for all intents. One side is connected to the intake before the throttle body, and the other is connected after the throttle body. The electrical connection is a heater. When cold, the valve opens and bypasses air around the throttle, raising the rpms. Once the heater warms up the valve, (think electric choke), the valve closes. The vehicle then runs standard idle rpm based on throttle body idle screw and Air Flow Meter idle screw settings.

 

 

Correct....I was thinking the same thing...sort of :huh: :D ...The pic above was only reference to the air reg/choke.

Here is the stock 200sx AIS.....for idle adjust.

 

 

 

I believe the FICD term (Fast idle control device) is relative and or for the upgraded 240sx EFI version.....not the 200sx....?

Same shit...newer technology ;)

[HRH]

Hmm, well that clears up a few things. I'm thinking it will run just fine the way it is, but it won't have a fast idle for cold startup, which really doesn't bother me. I've driven vehicles without chokes before. Just have to keep on the gas a little until she warms up.

[HRH]

Well today I pretty much worked on mowing the lawn, cleaning up junipers, and went for a bike ride with a friend and the dog. I finally got some motivation to go work on the car after spending 3 hours after the bike ride in the lawn chair bullshitting with Ericka. It was hot today, probably about 86, which was really nice. Sadly, the motivation I got was only enough to make this cheesy bracket to hold the MAF, but at least I got something done on the car! :)

 

[LenRobertson]

Those of us avidly following "Matt's FI Adventure" are happy to see any post on your project! A guy over the the Bluebirds list recently posted he is back working on a long stalled 510 project. He has vowed to work at least 15 minutes a day doing something on it. Finding parts if nothing else. I've been trying to do that myself, although in reality I'm not hitting it every day. And of course the days when several hours can be spent are where the real progress is made. I got home from work yesterday, hot and tired, but amazingly, I didn't park my butt in front of the computer right away. I went out and stuck the lower radiator hose on the 510, and mowed some lawn, things I won't have to do today.

 

I just looked over on your website, and was amazed to see the new paint job. Looks like what I want to do to mine. I need to have Reg straighten out the passenger side pillar so the new door will hang right, and throw a different front fender on. Then I'll have a multicolored car which looks a little tacky, even by my low, low standards. But I'm too cheap to buy a paint job, so rattle cans it'll have to be. I don't mind seeing nice paint on a 510, but I want some Rat in mine. Cheap n sleazy and proud of it.

 

I think that DQ FI article mentioned needing a fuel return line. Any idea if the vent line to the tank from the little valve thingy on the driver's side fender can be somehow used for this? Maybe a return line isn't even needed. I suppose Joe knows about this if you have chance to ask him.

 

Len

[Unclejesse88]

Speaking of MAF's, I just wanted to make a quick point. Mass Air Flow Sensors and Air Flow Meters (AFM is what you have) are two very different animals. As you've already mentioned, the Air Flow Meter uses the flapper door attached to a potentiometer to directly measure air flow. MAFs use either a hot wire or hot grid to (in)directly measure air flow. The hot wire is heated to a certain temperature, then the sensor measures current flow on the hot wire to infer air flow. The more air going over the hot wire, the more current it takes to keep the wire at a certain temperature, therefore it's inferred that more air is flowing into the engine. All of this is done inside the MAF sensor itself, and then sent to the ECU as a voltage. I also wanted to mention there are many places online covering modifications and adjustments(rich/lean) of the air flow meter, if you find that is something you need to do once you get this thing running.

 

(there is also another air sensor, and at least Toyota used it. It is similar to a MAF, but measures the frequency pulses of the incoming air. I think this is the least common style of sensor)

[Sealik]

Speaking of MAF's, I just wanted to make a quick point. Mass Air Flow Sensors and Air Flow Meters (AFM is what you have) are two very different animals. As you've already mentioned, the Air Flow Meter uses the flapper door attached to a potentiometer to directly measure air flow. MAFs use either a hot wire or hot grid to (in)directly measure air flow. The hot wire is heated to a certain temperature, then the sensor measures current flow on the hot wire to infer air flow. The more air going over the hot wire, the more current it takes to keep the wire at a certain temperature, therefore it's inferred that more air is flowing into the engine. All of this is done inside the MAF sensor itself, and then sent to the ECU as a voltage. I also wanted to mention there are many places online covering modifications and adjustments(rich/lean) of the air flow meter, if you find that is something you need to do once you get this thing running.

 

(there is also another air sensor, and at least Toyota used it. It is similar to a MAF, but measures the frequency pulses of the incoming air. I think this is the least common style of sensor)

 

Excellent info....

..

I'm thinking he's using the 81-82 Z20/22 ECU(M)...?.....flapper it is

My AFMs access (door) is bungy corded shut.....on the fly 'clock' spring tension adjust. :w00t:

[HRH]

Good info unclejesse! I hadn't gotten around to thinking about that yet, but it certainly makes sense. And I have some vague recollection of massaging the spring like Sealik has from an article long ago. Think it was when I had the Miata, but I ended up having a MAF instead of the earlier AFM.

 

And tonight I made a hell of a racket with some new 3M cutoff wheels purchased from work. Chopped off some mounting tabs from the 280z leftovers, cut all the tubes off the 200sx rail, and chopped off the ends then sanded them all. Got everything ready to weld. Too late to start doing that tonight. Hopefully I can weld these up fairly easily and not have birdshit all over. Think I'll probably do a couple test sections off that old 280z rail that's all effed up.

 

Oh, and yes Len, you can use the stock return line to the tank since it's fairly low pressure.

 

 

[Farmer Joe]

so what happend with this? any updates?

[HRH]

Still in progress. If you didn't check out the D21 timing rattle thread, I've been sick, finally got over that, and then the truck broke. Got it all fixed yesterday, so the 510 is back in the loop for actually working on it. I'd like to get it done soon, haven't worked on it in two weeks or so.

[Farmer Joe]

ahh, mkay.

 

bein sick really sucks ass...

 

anyways, look forward to some more progress on this!

[HRH]

I'm working on her as we speak!! :) Trying to get the fuel rail mostly done today, and maybe the fuel pump mounted.

[HRH]

Okay, tonight I started work on the 510 again. Dropped off the fuel rail at Joe's, he's working on that. Took a 60mm hole saw to the firewall tonight to fit the gigantic rubber doughnut housing the wires to the ECU, got those all run, haven't mounted the ECU yet, spent a few hours probing connectors with the VOM. Found out where most everything goes and needs to be hooked up.

 

Still have to run the fuel pump somewhere, and need to send new wiring back there. Really want to yank the whole engine and replace the entire harness, but then I'd never finish the 510. I'll save that for another 510 in the future. Probably one that's moar prettier from a bodywork standpoint.

 

Anyway, after the pump, some wiring, relays, etc, it should be just the fuel pump and some lines and then she'll pretty much be ready. Trying to work on her more lately since I've been dragging ass on this project.

[ariascarlos1990]

Any updates? Just read entire thread now I'm needing an update. ;)

[HRH]

Well, not really. I yanked an external pump off a late 280zx and was looking at fitting that in today. Unfortunately, the inlet is 3/8 while the outlet is 1/4 inch. But the fuel tank outlet is 1/4 inch on the 510. So either I need to make an adapter for 1/4 to 3/8, or I need to find a different pump with similar pressure with 1/4 in and out. Think I'll take a look and see what we have at NAPA for a stock 200sx fuel pump. Might have a semi-cheap NAPA fuel pump that will work. I know we have tons of pumps easily fitted to carbed vehicles. Usually don't go looking for external fuel injection pumps. And since I'm doing it on the cheap, I may research at work and then go pull a different pump at pull and save.

 

So no, no progress has been made, this my weekend. But I did haul 4 cubic yards of bark and weed around my tree, put weedcloth down and start filling that in. Fuck those weeds! No more in that section for me I hope. That was kind of what I did today. HL down the street (that's his name, funny how it corresponds to Datsuns!) needed bark too. He got 3 cubic yards, I just needed the 1, but I may need more.

[LenRobertson]

Oh yeah, yard work. You need to put in a big veggy garden, to take up even more of your time. Eating green peas right off the vine is really yummy, but time spent weeding and watering is less Datsun time. At least my wife mows the lawn, when I can keep the riding mower running. I should buy a better, bigger rider, but that money could be spent on Datsun parts. Everything is a trade off.

 

I found the pump from the '81 Z20 200SX I stripped, if there are any measurements you need. I also have the factory shop manual, which may have a GPM spec. But you probably have this info through NAPA sources. I'm curious if you use the stock 200SX ECU, does that limits the GPM you ever need? Until you go to a tunable ECU, do you need a high output pump? But I suppose when you rally, you use full throttle for longer periods of time than street driving.

 

Looking forward to you getting your 510 running. I sit out on the combine thinking about FI vs SUs, trying to decide which way to go. I'm leaning toward SUs, just cause they looks cool. I went to the Brit car show a week ago, and saw a lot of SUs. I'm already thinking I should have bought your SUs, but I knew I couldn't look at them for 2-3 weeks, and didn't want to hold you up. You sure didn't have any trouble selling them. But if your FI project works well, I already have a lot of the parts to go that direction.

 

Len

[HRH]

What's the inlet size on your 200sx pump Len? Is it a gigantic 3/8s? From what I've been able to find, they're mostly a Bosch style pump with a big inlet and small outlet.

[LenRobertson]

What's the inlet size on your 200sx pump Len? Is it a gigantic 3/8s? From what I've been able to find, they're mostly a Bosch style pump with a big inlet and small outlet.

 

Fitting coming straight into end of the pump is almost 1/2". Fitting coming out of side of the other end of pump is about 5/16". This one goes into a 90 degree hose going to what may be a pressure regulator attached to the side of the pump. However, there is a spot of yellow paint on the pump body, so it may be a junk yard replacement pump, hence non-original.

 

As far as making an adapter for different hose sizes, I'm picturing fittings with male thread on one end and hose barb on the other. Two different size barbs, hooked together with a pipe coupler. But I don't know if restricting the inlet to these type pumps is a bad idea or not.

 

Len

[HRH]

That's what I'm thinking. The pump is rated for 70 psi, which is quite a lot. I think that's the reason for the uber-large inlet, hence the fuel tank outlet should probably match. One more thing to do I guess.

[LenRobertson]

I believe the guy who did the DQ FI article used the stock SX pump. It might be worth rereading the article I linked to (1st page of this thread, I think). Since you have the 280 pump already, it might be worth trying it. It may work fine. As far as reducing the size of the supply line and starving the pump, seems that would only happen if you were using max amount from the outlet. Probably won't happen with a 4 cylinder. I'll look up what the factory SX manual gives for a volume and pressure spec.

 

A place to check for an adapter or fittings to make one is Spray Center on Highway 2 just east of Hayford Road. They are back by the Schwann warehouse place, south of Highway 2. They may have a one piece reducer in chem proof plastic, or maybe stainless steel fittings to make something. However, they may not have anything in small sizes like you need. They are nice guys to work with.

 

Len

[HRH]

I went back and looked at one of the DQ articles, mentions he used a 200sx pump. Article seems rather disappointing, especially mentioning "if in doubt cut it off, and let the next guy worry about the missing bits" in regards to the wiring harness. WTF? That's major wrecking yard bad karma, and sloppy to boot. I'm guessing this is a pretty old article though, copyright is 1997. He also says chunky cam won't work but I know of two running examples with high compression and chunky cams that work just fine. It also mentions cutting into the wiring harness. Good grief? I don't get that. I yanked the entire thing and aside from hooking up a few power and ground, there shouldn't be any need for cutting, especially when I'm trying to bypass as much of the original 510 wiring as possible.

 

Anyway, my whole point was I didn't see any discrepancy on the inlet size of the pump. Sooo.. Yeah. Going to go fart around in the garage. Joe says he's going to try and have my fuel rail done today. And I get to have two cavities filled at 12:30 at the dentist. Fun fun!

[INDY510]

You probably know this,,,, , but my KA24DE is spliced into the stock datsun wiring.......... because the ECU needs to know when you are cranking the starter

 

 

I think it cuts power to the fuel pump when the starter is turning to prevent a fire or something

 

The S13 Orange wire goes to ECU to cut power during cranking......... the 200sx must have a starter signal wire

 

 

Off the ignition switch:

 

Blk/wht wire tells the ECU when the key is in the "ON" posistion........... it seems like this wire is the main power source for the whole system

[HRH]

Yeah, the Chilton's manual I have for the 200sx does a decent job of wiring schematics. So far looks like there are only one or two wires that need power and a few grounds, that's it. The KA is a lot more advanced than the 200sx system. My original Datsun wiring is pretty crappy, so I've bypassed it to an aux. fusebox for anything important. I'd actually like to yank the whole harness and rebuild it, but I'd rather find a good donor car with a harness I can do that to. That way I won't have to worry about more downtime than I already have.

 

As far as I know the 200sx doesn't have a fuel cut for the fuel pump, or if it does it's done with relays. Either way I'll be wiring the pump separate of the ECU so I can turn it off for safety and troubleshooting should the need arise.

 

My right cheek is still all numb, I can't eat my Snickers bar. :( And f me, I hate going to the dentist. Damn two cavities cost me $140, and I'm damn lucky I have insurance. Total bill was about $582.

[INDY510]

Nevermind......... it looks like the blk/ylw wire doesn't go to the ECU at all

 

 

Icehouse's S13 diagram shows a orange wire to the ECU for a starter signal

 

 

The 200sx must have a starter signal wire to cut the fuel pump while cranking the starter