510 L20B EFI conversion - the project is finished!

[LenRobertson]

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.

Great news! Wonder if something in all the 30 year old components was sticky or tarnished and finally decided to come back to life. I'm with motavated on wanting FI, but wondering what sort of nightmare it might be for me. I think I'd have given up way before you did. I'm not sure I remember a thread where someone had so much trouble, but kept on going. Very inspiring! Years from now, old Ratsuners will be telling young ones about HRH who wouldn't give up on a seemingly unsolvable problem.

 

Was your visit to the judge yesterday, or a week away? I wondered yesterday if you were over there in Davenport. I did think of a good excuse to tell the judge - "My hemorrhoids were just killing me, and I was hurrying to get home and treat em." Odds are the judge has the same problem, from years of sitting all day, and will be sympathetic.

 

Len

[HRH]

You know, I did mention to the judge I had hemorrhoids; I asked if he minded if I stood due to that fact! He reduced my ticket by 88 bucks which was worth driving there. My mitigating circumstances was I was trying to get back home a little quicker to attend to Molly who would have been neurotic after spending the whole day by herself.

 

As for the car, I wish I had a better idea. I haven't tried starting it this morning yet after it's bone cold. Probably will just for shits and giggles. Can't help thinking it had something to do with the aux. pos wire that's attached to the battery cable that goes to my fusebox for all the EFI and shit. But that doesn't hold water because it's attached to the battery cable, and the other harness is attached to the alternator wire, etc. Think I'm going to double check that fusible link to the alternator. Maybe take it out and wire in a blade fuse.

 

Next up is a quieter muffler. I'm done with the loudness. Sounds cool, but it's just too loud.

 

And no Todd, I did not know Steel Panther was playing Seattle! Ha, that's awesome!

 

Thanks to all who helped and provided pictures for this thread. I'll continue giving updates once I fully test the car and make sure driveability is what I think it is.

[LenRobertson]

Good to hear you were somewhat successful in court. I've heard if the officer who wrote the ticket fails to appear, the judge has to throw it out. Maybe an urban legend, but if true, it would be worth appearing in court on a large $ ticket, just in case.

 

When I first got my 200SX running, I had misc. electrical weirdness. Tach and other gauges would come and go. I finally traced it to one of the two fusible links having a break in it. Sometimes it would pass current, and then decide not to. The outer insulation showed no sign of melting, like it is supposed to do when the link burns out. I grabbed another fusible at Pull n Save and installed it. Worked fine since. It is a cheap and easy fix for a suspected problem. I've seen a link on wiring in new fusible link wire, but a blade fuse might be even better. I don't know if a fusible works as a sort of slow blow fuse - only a dead short will cause it to burn out. If there is a problem with the blade type, you can always go back to fusible.

 

Len

[HRH]

Ah hah, and the other shoe drops! Went out and tried to start it this morning. Sputter pop, won't run unless I make a big vacuum leak, and even then won't run worth two shits. Ran just like it had the night before. Tried clamping the positive cable, made no difference.

 

This tells me something though, it's probably heat related. Other question, should it matter which side of the air regulator goes to either end? I can't imagine it does as you can blow through it, just curious.

 

I think the next thing I'm going to look at it the temp sensor wire and see if there's high resistance in that. After that, not sure. I might go take a blow drier to various parts and see if that makes a difference. I'm pretty sure it's a wiring issue now though.

 

Oh, and I can rule out the ECU, I know that's not the problem since we tested all of them in Joe's truck and they all operated fine. Has to be a harness/sensor issue.

[Sealik]

Ah hah, and the other shoe drops! Went out and tried to start it this morning. Sputter pop, won't run unless I make a big vacuum leak, and even then won't run worth two shits. Ran just like it had the night before. Tried clamping the positive cable, made no difference.

 

This tells me something though, it's probably heat related. Other question, should it matter which side of the air regulator goes to either end? I can't imagine it does as you can blow through it, just curious.

 

I think the next thing I'm going to look at it the temp sensor wire and see if there's high resistance in that. After that, not sure. I might go take a blow drier to various parts and see if that makes a difference. I'm pretty sure it's a wiring issue now though.

 

Oh, and I can rule out the ECU, I know that's not the problem since we tested all of them in Joe's truck and they all operated fine. Has to be a harness/sensor issue.

 

 

Interesting.....any pics on your air reg setup?

Temp sender will shorten or lengthen injector pulse time.....relative to engine temp

[bilzbobaggins]

damn...was reading and thought it went right for you.....good luck on finding it....i just got a 80 200sx factory service manual off ebay today....ill hunt my scanner down if you need something scaned up.....good luck

 

jeff

[I'm BLUE]

how are the hemi's ? :lol:

[LenRobertson]

Other question, should it matter which side of the air regulator goes to either end? I can't imagine it does as you can blow through it, just curious.

 

Pic in the FSM shows the air regulator Inlet is the end away from the electrical thingie, and the Outlet is on the same end as the electrical. I suspect the airflow to the bimetal unit is different if it is installed backward. Air regulator test - ohmmeter + to pin 21, - lead to body ground. Meter should read 25 to 90 ohms. Then with meter leads hooked the same, switch to voltmeter: 1.Disconnect starter motor "S" terminal. 2.Connect battery ground cable. 3.Ignition "Start". Should read battery voltage. It looks like the stock wiring for the regulator is from the fuel pump wire and relay, so testing for voltage may not be quite the same for your system.

Good to see bilzbobaggins may be able to scan pages from the manual. Seeing some of the FSM pics and diagrams will be a lot clearer than my translation of the book.

 

Len

[HRH]

No, I've appreciated all the regurgitated info Len! Question, does the book list what resistance the water temp sensor should be at when cold vs. hot?

 

I'm actually happy. I know roughly where the problem is now. Even though it went away, the saying I have keep popping up in my mind. That is: "Problems that go away by themselves will come back by themselves."

[LenRobertson]

No, I've appreciated all the regurgitated info Len! Question, does the book list what resistance the water temp sensor should be at when cold vs. hot?

 

I'm actually happy. I know roughly where the problem is now. Even though it went away, the saying I have keep popping up in my mind. That is: "Problems that go away by themselves will come back by themselves."

What the FSM calls "Cylinder Head Temperature Sensor Test": Ohmmeter + lead to pin 14, minus lead to body ground. 68 degrees F or above should read below 2.9k ohms. Below 68 F 2.1k ohms. The book shows sticking the tip of the removed sensor in water and taking ohm readings as the temp rises, with a graph of values. If you want to try that, I can give some values from the graph. But it says if the test through the harness pin is okay, you don't need to do the hot water test.

 

How about "Air Temp Sensor Test"? + lead to 25, minus lead to 34. Intake air temp 68F or above should read below 2.9k ohms. Temp below 68F 2.1k or above.

Then "Insulation Resistance": + lead to 25, minus lead to body ground should read infinite ohms.

 

Len

[Sealik]

Pic in the FSM shows the air regulator Inlet is the end away from the electrical thingie, and the Outlet is on the same end as the electrical. I suspect the airflow to the bimetal unit is different if it is installed backward. Air regulator test - ohmmeter + to pin 21, - lead to body ground. Meter should read 25 to 90 ohms. Then with meter leads hooked the same, switch to voltmeter: 1.Disconnect starter motor "S" terminal. 2.Connect battery ground cable. 3.Ignition "Start". Should read battery voltage. It looks like the stock wiring for the regulator is from the fuel pump wire and relay, so testing for voltage may not be quite the same for your system.

Good to see bilzbobaggins may be able to scan pages from the manual. Seeing some of the FSM pics and diagrams will be a lot clearer than my translation of the book.

 

Len

 

 

You can see the stock air reg placement on a previous pic I posted

[datzenmike]

how are the hemi's ? :lol:

 

Keep your hemis clean as possible. Use baby wipes. Dry thoroughly.

 

Avoid foods that cause constipation and eat lots of fruit and veggys. Add oat or wheat bran to your diet. Avoid straining when going.

 

Avoid prolonged standing if possible.

 

Avoid lifting heavy objects.

 

Relax as much as possible, reduce stress, hot baths instead of showers.

 

Use preparation H

[HRH]

Actually, I've found Preparation H doesn't do shit Mike! :) Literally and figuratively! And I can't keep them clean, they're up about 3 or 4 inches. The steroid suppositories are doing their job I think though. It's starting to feel better. The epsom salt baths and using as a laxative works quite well. That's been the best option so far.

 

And let me tell you, the thing they stick in your butt to guide the camera up is like a small cock. It's HUGE! Like 3 inches long, and about an 1" diameter. Then after that's crammed up there, then the camera goes up. That's a whole new sensation I'd rather not care to have. Then after that, the finger goes up to inspect! Holy shit, thought I was going to die the other day. At least it feels better now, thanks for asking DTP! :D

 

On to the car:

 

The air temp sensor that you mentioned Len, I don't think that's on my harness, just the head temp sensor. I may go after that first seeing as I did extend the head temp sensor wires due to a broken plug. And it seems to be okay once the temperature warms up, so that's as good a place to start as any. I also just remembered I don't think I've checked the fluid in the radiator after I removed the thermostat housing. I'm wondering if there's not much water reaching the temp sensor. Not sure that would affect things to the sensor though. If anything it should cause it to think it was hot. Not sure, I'll check on Sunday.

 

I'm pretty sure from the description that I have the air regulator hooked up correctly.

[LenRobertson]

The air temp sensor that you mentioned Len, I don't think that's on my harness, just the head temp sensor. I may go after that first seeing as I did extend the head temp sensor wires due to a broken plug. And it seems to be okay once the temperature warms up, so that's as good a place to start as any. I also just remembered I don't think I've checked the fluid in the radiator after I removed the thermostat housing. I'm wondering if there's not much water reaching the temp sensor. Not sure that would affect things to the sensor though. If anything it should cause it to think it was hot. Not sure, I'll check on Sunday.

 

Maybe the '80, non-O2 system didn't use an air temp sender. Bilzobaggins, since you have an '80 book, could you look that up? At the start of the "Engine Fuel" section in the '81 manual is a diagram of the fuel system and components. Probably something similar in the '80 book.

Matt - The air temp sensor is built into the air flow meter. Does your AFM have a plug with no wires going to it? The book says the air temp sensor "...transmits a signal for the fuel enrichment to change the pulse duration." Also "The temperature sensing unit employs a thermistor which is very sensitive in the low temperature range." If your ECU is "looking for" a signal from an air temp sender and not getting it, I don't know what happens, but maybe screws the pulse duration. In the trouble shooting chart for "Running Rich", checking the air temp sensor was one of the things mentioned. Maybe find out if Joe is running air temp on his systems. Also, check your harness for snipped off wires that may have gone to the sensor. I can look on my '81 harness and see where the wires come out of the harness, but it will be hard to describe. Any chance NAPA sells this sensor, or air flow meter? You could see if '80 and '81 use the same part number.

Could this be "The Answer" to your running rich problems? Nah, probably not, but it is another think to check on.

[Sealik]

Maybe the '80, non-O2 system didn't use an air temp sender. Bilzobaggins, since you have an '80 book, could you look that up? At the start of the "Engine Fuel" section in the '81 manual is a diagram of the fuel system and components. Probably something similar in the '80 book.

Matt - The air temp sensor is built into the air flow meter. Does your AFM have a plug with no wires going to it? The book says the air temp sensor "...transmits a signal for the fuel enrichment to change the pulse duration." Also "The temperature sensing unit employs a thermistor which is very sensitive in the low temperature range." If your ECU is "looking for" a signal from an air temp sender and not getting it, I don't know what happens, but maybe screws the pulse duration. In the trouble shooting chart for "Running Rich", checking the air temp sensor was one of the things mentioned. Maybe find out if Joe is running air temp on his systems. Also, check your harness for snipped off wires that may have gone to the sensor. I can look on my '81 harness and see where the wires come out of the harness, but it will be hard to describe. Any chance NAPA sells this sensor, or air flow meter? You could see if '80 and '81 use the same part number.

Could this be "The Answer" to your running rich problems? Nah, probably not, but it is another think to check on.

 

 

That 'air temp sensor' in the AFM is different than the water temp sensor(1980) and the head temp sensor (1981).

It's just little plastic knob sticking out in front(?) of the flap.

I believe that one in the AFM just measures the temp of the air going into the engine.

I think all of the AFMs have them....?

No extra plugs or wires/plugs on the AFM for this.

 

The O2 engines still had the air reg.......basically a choke.

Edited October 30, 2010 by Sealik

[LenRobertson]

That 'air temp sensor' in the AFM is different than the water temp sensor(1980) and the head temp sensor (1981).

It's just little plastic knob sticking out in front(?) of the flap.

I believe that one in the AFM just measures the temp of the air going into the engine.

I think all of the AFMs have them....?

No extra plugs or wires/plugs on the AFM for this.

 

The O2 engines still had the air reg.......basically a choke.

Thanks for clearing this up. I never thought of the air temp sensor being wired through the AFM plug. Pretty obvious now that I finally went over and got my '81 AFM (I'm tempted to bring the entire Z20e into the house by the computer, just to follow this thread. But I do have a wife, so that might not be the best idea}. Looking at the '81 AFM, it has a plugin with 5 blades, numbered 34, 35, 33, 32, 25. From the test procedure in the FSM, these all correspond to the tests for AFM and air temp sender.

 

You also cleared up my confusion on the different engine temp senders. I didn't realize the two different year engines measured head temp in different ways. So the test I posted for "Cylinder Head Temp Sensor Test" may not be valid for the '80 water temp sender. Another thing someone with an '80 shop manual can check.

 

Len

[Sealik]

Matt............I'm somewhat having non oic anxiety issues...... :D

I need a fix.. :frantics: ....... :)

[bilzbobaggins]

ill look it up when i get home...im at work and jfc, these are some dead lanes....

 

jeff

[bilzbobaggins]

Yes. The diagram shows a Air Temp. Sensor in the AFM.

 

I cant get the gd scanner out of the closet due to sleeping bear, er wife...

 

Ill have to get it out tommarow afternoon.

 

Let me know if you want anything else scanned.

 

jeff

[HRH]

Sorry guys, didn't get a chance to work on it this Sunday. Trying for Thursday.

[Sealik]

Yes. The diagram shows a Air Temp. Sensor in the AFM.

 

I cant get the gd scanner out of the closet due to sleeping bear, er wife...

 

Ill have to get it out tommarow afternoon.

 

Let me know if you want anything else scanned.

 

jeff

 

The AFM was tested....so.....would assume air temp was also in that 'loop'?

I doubt it's that......I'm leaning towards vacuum/head temp sensor/IAS/AirReg...etc. :)

Combination of a few things...........Maybe :rolleyes:

No oics....?

Hmmmmmm.............how about a quick pencil sketch.....rendering? :D

Crap....never mind....would still need a camera :lol:

[bilzbobaggins]

sob...my scanner is too old..its a scanjet 5200cse and there are no drivers for windows 7....fuck

 

 

jeff

 

still trying

[motavated]

WTF is a ScanJEt?

 

Yep its old.... LOL!

[bilzbobaggins]

its an hp, but old.....explains why the father in law was more than happy to give it to us....cant get a picture worth a damn...

 

still trying

 

jeff

[LenRobertson]

jeff - I've seen pretty good results copying pages by shooting them with a digicam, but you need one with somewhat of a closeup range. Even without pics of the '80 manual, you can look up specs for the various bits n pieces. I'm really curious what your book says about the head temp sensor, or maybe it was called a water temp sensor in '80. Can you look at my post #335 on page 17 of this thread, and see if the '80 spec is the same? Maybe it is the same, even though the sensor is located in a different place. You might also be sure the pin number on the harness connector is the same as what I found in the '81 book. I'm really close to buying an '80 manual myself, just so I can see the differences between the two years. But that would just put me closer to following Matt down the FI path, and I'm not wanting to do that yet. Not until he wins this fight anyway.

 

Len