510 L20B EFI conversion - the project is finished!

[datzenmike]

http://cgi.ebay.com/...=item19bc39a2b2 ...... '80 5 speed

 

 

http://cgi.ebay.com/...=item51843ea7c2...... '81 5 speed California (02 sensor)

 

 

http://cgi.ebay.com/...=item518f280212 ..... '81 5 speed

 

 

http://cgi.ebay.com/...=item19bc780a42..... '80 automatic '80 automatic

 

 

http://cgi.ebay.com/...=item4aa12d9f30..... '81 5 speed California (02 sensor)

 

 

http://cgi.ebay.com/...=item27aa63d6ff..... '80 5 speed California (02 sensor)

 

 

http://cgi.ebay.com/...=item29fff24537 .....'80 automatic California (02 sensor)

 

 

http://cgi.ebay.com/...=item19b3e7ad86 .....Unknown, the number posted doesn't even match the label on the ECU. Looks like A11 631 741?

[LenRobertson]

I looked in the service manual, but don't see any ECU numbers. I Googled for a number list, but couldn't find anything on the early '80s models. Of course, my search skills are lousy, so someone else may be able to find a list and post the link. You are welcome to borrow my ECU, wiring harness, whatever I have, but it is all from an '81 that I know had an O2 sensor. I'm still puzzled (if I understood correctly) that Joe seems to be running an ECU that needs an O2 sensor, only he doesn't use the sensor. But maybe the O2 sensor isn't that important, it just sounds like it must be important. Maybe Joe can explain this one when you talk to him next. Actually, I suspect Joe is a wizard of some sort with magic powers. Things automotive will work for him that won't for the rest of us.

 

But I don't know when I'll get to Spokane next. Maybe a day this week, maybe not. Maybe Saturday, maybe not. Depends on work mostly. If it is worth the 50 mile drive to you, you are welcome to come and pick up whatever you need. I really think the factory manual will help find your problem when you have time to study it. I'm here today if you feel like a drive in the country.

 

Len

[LenRobertson]

My '81 ECU A11-626 575 is from an auto trans. SX. I can't remember if Calif. or not.

 

Len

[datzenmike]

My '81 ECU A11-626 575 is from an auto trans. SX. I can't remember if Calif. or not.

 

Len

 

 

'81 ECU A11-626 575 is Non California automatic.

[HRH]

Tested all the ECUs on Joe's truck, they all work fine. I did find I was screwing up the air regulator by having it open to atmosphere. Need to have it recirced past the AFM. Which would explain why it worked with a thumb halfway over the open hole. Also found out Katherine's car doesn't use an air regulator, but also has a stock cam, which would be why it can idle without, just the throttle plate is adjusted up a little. Also got an adjustable fuel pressure regulator from Joe.

 

So tomorrow before work I'll try and get the regulator up and running, which should solve one problem. The adjustable regulator should hopefully solve the other.

[Unclejesse88]

With the air regulator open to the atmosphere, you are getting "unmetered air". Meaning, air is going into the engine, but the ecu doesn't know about it because the afm isn't seeing it. This is essentially a vacuum leak. Note, some manufacturers run their pcv systems as unmetered air. Presumably, the ecu just assumes "x" amount of air is flowing from the pcv. Either way, this is why it is important to know how the factory intended the systems to operate. I see way too many cars with the little K&N filter on the valve cover breather. Most systems were not intended for the pcv to be unmetered. The only way these people get away with it is the ecu is usually advanced enough to compensate for it. In your case, the ecu is so basic it has no idea that the air regulator is letting in unmetered air.

[Sealik]

With the air regulator open to the atmosphere, you are getting "unmetered air". Meaning, air is going into the engine, but the ecu doesn't know about it because the afm isn't seeing it. This is essentially a vacuum leak. Note, some manufacturers run their pcv systems as unmetered air. Presumably, the ecu just assumes "x" amount of air is flowing from the pcv. Either way, this is why it is important to know how the factory intended the systems to operate. I see way too many cars with the little K&N filter on the valve cover breather. Most systems were not intended for the pcv to be unmetered. The only way these people get away with it is the ecu is usually advanced enough to compensate for it. In your case, the ecu is so basic it has no idea that the air regulator is letting in unmetered air.

 

 

That's why there was no fluctuation in RPM when the flap was moved by hand....?

Correct?

[HRH]

Yeah, the funny thing was I was thinking air regulator=unmetered metered air leak. Where really it's a metered air leak. I don't think that's why there was no fluctuation when the flap was moved by hand. I had the vacuum leaks taped off and untaped, and I've dicked with it so much I can't remember exactly which was where when I played with the flap. Also, I don't know that it would be noticeable at idle with all the cam overlap.

 

My curiosity is if it sucks from the intake tube behind the AFM, then goes up into the manifold, it would seem like it's still a leak, but also that the same amount of air goes in either way. It's a rather hard concept for me to grasp. I likened it to water, in which case the additional suction from the manifold will suck some off the main volume. Still not sure. What I do know is if I hook it up correctly, things should get better. If they don't then I'll know something else is afoot.

 

I've taken a break for tonight. I soaked my hemorrhoidal ass in the tub with some Epsom salts. If you've never had one, try not to get them. It's like someone is stabbing you in the asshole with a red-hot poker every time you shit. :D Sorry for the visual, but I feel like sharing my pain tonight. I do feel better after the hot bath though.

 

By the way, how do you have the PCV routed Sealik? Anyone know how the stock 200sx system was? As Unclejesse mentioned, I'll try and set that up as original too. Right now I have a breather on the crankcase vent and the valve cover going to the pcv on top of the manifold. I think that will work but not 100% if you all have some input.

[Sealik]

Yeah, the funny thing was I was thinking air regulator=unmetered metered air leak. Where really it's a metered air leak. I don't think that's why there was no fluctuation when the flap was moved by hand. I had the vacuum leaks taped off and untaped, and I've dicked with it so much I can't remember exactly which was where when I played with the flap. Also, I don't know that it would be noticeable at idle with all the cam overlap.

 

My curiosity is if it sucks from the intake tube behind the AFM, then goes up into the manifold, it would seem like it's still a leak, but also that the same amount of air goes in either way. It's a rather hard concept for me to grasp. I likened it to water, in which case the additional suction from the manifold will suck some off the main volume. Still not sure. What I do know is if I hook it up correctly, things should get better. If they don't then I'll know something else is afoot.

 

I've taken a break for tonight. I soaked my hemorrhoidal ass in the tub with some Epsom salts. If you've never had one, try not to get them. It's like someone is stabbing you in the asshole with a red-hot poker every time you shit. :D Sorry for the visual, but I feel like sharing my pain tonight. I do feel better after the hot bath though.

 

By the way, how do you have the PCV routed Sealik? Anyone know how the stock 200sx system was? As Unclejesse mentioned, I'll try and set that up as original too. Right now I have a breather on the crankcase vent and the valve cover going to the pcv on top of the manifold. I think that will work but not 100% if you all have some input.

 

You do realize that you'll have to get that lanced..... :lol:

I'll post some pics on the PCV etc.

[HRH]

Actually I talked to Greg over at Joe's shop and his advice was have them cut it out. You'll bleed for 5 days, but the pain will go away instantaneously and it's better than suffering for two weeks. He had a few, one when he got married? Hmmm. :) Fortunately I seem to be getting better quickly. The last one took a week to go away. I'd like it if it wasn't too painful at work tomorrow.

[I'm BLUE]

More Fiber in diet ,,, don't push HARD when pooping <--- part of the cause from what I understand ? ( something about veins growing ? IDK ),,,, ( if you need ohhhhh shit handles on the thrown your in deep shit pushing too hard :lol: ) ,,,,

[Icehouse]

Well I did it. I re-read pretty much everything! Dude I would be very frustrated as well. Shit I've had problems but damn! first the EFI then your ass.... Fuck.

 

Well I had a few ideas but I don't really understand that old ass ECU. I can't believe that the TPS is a two stage switch, are you sure? Do you have two plugs that go into the TPS? Are you hooking the TPS wires into the black cube on the TPS? If it's on the KA or VG TPS those are for automatics only. Sucks your so far away. I would like to check it out for fun. Does anyone have the wiring diagram for the engine? Like one they could send me. Or even better a copy of the FSM. I would expect a slightly rich idle since it's a non hemi head, single cam KA's idle kinda rich to IMO. How does it compare to your truck. I know when I walk behind mine it about kills me when it's cold. I will keep thinking..

[Sealik]

From top of pic....on plenum

1-'PCV' connection for air reg.

2-IAS connection

3-Connection for the fuel regulator. This tees off a larger fitting for the other air reg connection.

Lower end of air reg is attached to air pipe

 

 

 

 

 

 

 

 

 

 

 

 

[Sealik]

Yeah, the funny thing was I was thinking air regulator=unmetered metered air leak. Where really it's a metered air leak. I don't think that's why there was no fluctuation when the flap was moved by hand. I had the vacuum leaks taped off and untaped, and I've dicked with it so much I can't remember exactly which was where when I played with the flap. Also, I don't know that it would be noticeable at idle with all the cam overlap.

 

My curiosity is if it sucks from the intake tube behind the AFM, then goes up into the manifold, it would seem like it's still a leak, but also that the same amount of air goes in either way. It's a rather hard concept for me to grasp. I likened it to water, in which case the additional suction from the manifold will suck some off the main volume. Still not sure. What I do know is if I hook it up correctly, things should get better. If they don't then I'll know something else is afoot.

 

I've taken a break for tonight. I soaked my hemorrhoidal ass in the tub with some Epsom salts. If you've never had one, try not to get them. It's like someone is stabbing you in the asshole with a red-hot poker every time you shit. :D Sorry for the visual, but I feel like sharing my pain tonight. I do feel better after the hot bath though.

 

By the way, how do you have the PCV routed Sealik? Anyone know how the stock 200sx system was? As Unclejesse mentioned, I'll try and set that up as original too. Right now I have a breather on the crankcase vent and the valve cover going to the pcv on top of the manifold. I think that will work but not 100% if you all have some input.

 

Need some updated pics

[LenRobertson]

By the way, how do you have the PCV routed Sealik? Anyone know how the stock 200sx system was? As Unclejesse mentioned, I'll try and set that up as original too. Right now I have a breather on the crankcase vent and the valve cover going to the pcv on top of the manifold. I think that will work but not 100% if you all have some input.

 

Drawing in the '81 FSM in the section "Crankcase Emission Control System" shows a tube from the side of the crankcase, to the PCV valve which is shown directly on the bottom of the intake manifold. The book shows a butterfly labeled "Throttle Chamber". So the PCV valve is between the throttle butterfly and the intake valves. However, the drawing shows a tube from the valve cover to the other side of the butterfly (air filter side of the butterfly). It sounds to me like you have both going into intake manifold, but whether that matters or not I don't know. There is a second tube from the intake manifold to the outboard side of the butterfly, with an "Idle adjusting screw unit" in it.

 

As to Icehouse's TPC question, the wiring diagram shows 3 wires going to the "Throttle Valve Switch". #29 goes to the side of the switch labeled "Idle". #24 goes to the side of the switch labeled "Full". #30 goes to what looks a solid black line connecting 29 and 30. I suspect this line represents a moving part of the switch, but don't know. All three wires go directly to the ECU. Nothing else connects to them. I think I posted the test for the Throttle Valve Switch. If not, I can.

 

It is too bad my computer skills are so lame, and I can't scan and post from the manual. My wife unloaded Photoshop Elements from my computer, and now it won't reload, or at least my Dell from Hell can't find it if it is loaded. My wife has the skills to scan and post, but she is Very Busy with projects she thinks are more important than Datsuns. Unbelievable, huh?

 

Len

[Sealik]

Here's the PCV tube from crankcase connected to plenum

 

 

[LenRobertson]

Sealik - On your system, does the breather tube from the valve cover enter the system between the throttle body and the air flow meter?

 

Len

[Sealik]

Sealik - On your system, does the breather tube from the valve cover enter the system between the throttle body and the air flow meter?

 

Len

 

Negative.

Just have a short hose and filter on it.

 

[HRH]

Sorry, haven't gotten a chance to fix my air regulator yet, will probably get around to it on Thursday. Have that off so I can go to my court date for the speeding ticket. Len, you want to be a character witness on my behalf? :) j/k.

[LenRobertson]

Right now I have a breather on the crankcase vent and the valve cover going to the pcv on top of the manifold. I think that will work but not 100% if you all have some input.

If I'm understanding your setup, this is not the way the original system is rigged. Pipe from crankcase to PCV into manifold, yes. Hose from valve cover vent also into the PCV, no. Factory for that line is into the air intake ahead of the throttle valve, but Sealik indicates just a filter on it works fine. It seems to me this is pretty much the same as a factory carb setup, where the valve cover vent goes to the air cleaner. Maybe it doesn't matter if it goes to the PCV, but if you are trying to get things closer to factory, to eliminate unknown variables, this would be an easy one to fix.

 

Good luck on the court appearance. If I showed up as a character witness, and started mouthing off to the judge, they would probably jail me, or maybe both of us. All of Ratsun would have to come to Davenport WA to picket the jail. Some things you don't want my help with! But I do want to know how it works out for you. I hope you get the fine reduced enough to be worth going to court. Maybe we should start a new topic on "What I told the judge. (and he believed)."

 

Len

[Creepy Cruiser]

 

Good luck on the court appearance. If I showed up as a character witness, and started mouthing off to the judge, they would probably jail me, or maybe both of us. All of Ratsun would have to come to Davenport WA to picket the jail. Some things you don't want my help with! But I do want to know how it works out for you. I hope you get the fine reduced enough to be worth going to court. Maybe we should start a new topic on "What I told the judge. (and he believed)."

 

Len

 

Lol, that's funny

[HRH]

Are you ready for weird shit number 998?

 

So I hook up the air regulator correctly, try and start the car. Runs like shit, missing, still black rich smoke. So say f it and unhook the air regulator, make an air leak, start the car, starts right up. Cover it halfway with my thumb, thing idles. Shut it off, looking around, see my positive battery cable and decide since it's broken (on the list to replace) I'll put a pair of vise grips on it to secure the connection.

 

Then I put the air regulator back on, start the car, reattach the fpr to manifold vacuum, not the vacuum pump. Start the car and it runs great!? WTF?

 

Then I adjusted the idle screw up until the thing idles at 900-1000 rpm. Runs fine, no more black smoke except on WOT. Seems to hold steady throttle, still oscillating a little but I think it's because I don't have the exhaust fully hooked up and since the tach is staying steady I'm guessing reattaching the muffler and pipe would be a good idea. I wonder if I'm getting the sound of the stock header and it's not being smoothed out by a muffler of sorts. Like I said it never ran perfectly even when going down the freeway. Close, but not like a stock newer car.

 

Back to the battery positive terminal deal. So I call dad and his first thing is that doesn't make sense since the car had enough juice to start, shouldn't need to be connected. (Which I know, but why did it work?) So I take the clamp off. Still runs fine. Started it up a second ago with Buddy as my witness, yanked off the positive cable while it was running, still ran fine.

 

So I don't know if it had some fart in the harness, ecu, or what. But it runs now, and fairly decently! Restarted it a few times, hasn't let me down yet. Exceptionally happy, just wish I knew exactly why it got better.

 

Oh, and the doc says I only have a few hemorrhoids, but they're in a circle, so I have suppositories now. They're really not too fun, but my butt should be better in a few days. :D

 

Here's a video to celebrate!

 

[motavated]

FUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUKKKKKKKKKKKKKKYYYYYYYYYYYYYYYYYYYYYYYYEEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHH!

 

I want to go this route. But since you were having a hard time. I was rethinking this... GLAD MAN!

[jovial_cynic]

Congrats!

[Creepy Cruiser]

Rock on!!!

 

Hey Matt, did you know that Steel Panther is actually playing on Halloween night in Seattle?