DC871F

Hmm. Will a test unit determine a bad ECU, OB codes? I have talked to a couple different diagnostic shops, and they say its almost impossible to extract "relevant" information from a test unit for this vintage. I'm pretty sure the TVS is good. I have a new distributor on the way since I need a new VA can, plus maybe a little troubleshooting with a new ignition module. I really hate throwing part at problems, but it does serve a little purpose just to get the vacuum system back in shape. I was reading on a thread back a couple years ago, that someone had a cylinder dropping off, and after a bunch of troubleshooting, a new ignition module cured the problem. I admit, I am more of a venturi and float kind of guy, so at this point, I am doing OJT on this engine, but after reading that thread, I feel a little compelled to go ahead and invest a distributor and module. I do feel its dropping a cylinder, which make no sense, but I have been through most things twice at this point. ECU? Maybe a diagnostic code search is in order. Is that worth my time or should that be under the category of remove and replace?

I took AFM off the car, inspected under the cover, clean as a whistle. I also looked at the vane movement, felt nice and smooth, no hangups, not dirty inside the airflow side. It bogs in all gears, I was just giving an example. Deficiencies in communicating in this manner definitely rears its ugly head doesn't it? In 5th gear doing 65 MPH, you can stab the gas peddle to the floor, and notice the car being "held back", but if you do the aforementioned "throttling" of the gas peddle, sure enough you'll find the sweet spot and its off to the races. I really hate to go back through the fuel injection, but maybe theres something up there. But I dont want to muddy the watter quite yet.

ZCardepot resistor. I assumed it was 10 ohms, but reading it actually doesnt say. When I get back to it I'll measure it.

Man, another great idea, thanks. I got mine up on the front of the fuel rail. I really dont think the resistor is going to fix my problem. I tried it 10 different setting from high to low. Its the ZCarDepot resistor. I'm waiting for a distributor to arrive to hopefully find a cure. Accelerating through the gears, by the time you are up towards halfway through 3rd, it just stops accelerating, foot buried. But if you modulate your foot, you can find the sweet spot and it will go. I swear its dropping a cylinder. Timing is correct.

Mic check 1,2..

Installed resistor. Any offerings on how to set it? Trial and error? I set it mid-way and saw no change. Back it off a little, then went towards the other direction, still no change. There is definitely a sweet spot to where the car does accelerate cleanly, flooring it acts as if a cylinder is dropping off. Re-checked vacuum, found a small leak, but didnt change anything appreciable.

Just checked RockAuto, they have it in stock. A-1 CARDONE 19B156 {#44001F5490RE, 44001P7290RE} Reman.; Includes: Caliper, Hardware, and Bracket (Sweepstakes Entry!) Info Rear Right; with Metal Piston

Fuel pressure checks ok, Not quite 30 at idle, but a solid 37 at acceleration. I'm a PSI off, but may be the gauge.

Hey you're right. I was stuck in the frame of trying to read ground.

I did the test with it on the car. It just showed an open on all three terminals, not "0", or a large resistance reading. The ground I used was good. Re-installed TVS, took car out and drove it about 90 miles. There is definitely a "sweet" spot on the accelerator peddle, about 75-80% full throttle to where the car will accelerate smoothly. Also, I think the fuel consumption is way high, but that will have to wait till tomorrow to confirm how much gas it used, it may be the fuel sender lying to me. I will go out tomorrow and do the insulator test through the ECU plug, since last time I did all 3 tests with the TVS disconnected.

TVS clean, no defects I could see. Filed the contacts, cleaned, reinstalled. Still cant get it to pass the insulator test on p.82, whatever that test means. Maybe theres a short in the 3 prong plug, but it looks intact. Just for future reference for anybody else. You have to drill the 2 small pop rivets to get the cover off.

I did that about 25 years ago with a TurboZX, that was a huge mistake. And I was at work when I did it, it was a long herky jerky ride home, LOL.

It will be the first place I go this morning, after it warms up a little. Could have got 4 240Z's working in the time this ZX is taking.

Yeah, disregard, had the TVS disconnected, so....... Its 25 degrees tonight in N.FLA, been back and forth between fire place and garage, forgot to hook the TVS back up. So at least I dont have to chase wires tonight. So if the TVS does not pass the insulation test, I'll at least need to replace. Would this cause my issue?

Did the procedure on p.82. For some reason its not testing through the ECU plug. Testing the TVS directly I get continuity on the idle and full open throttle. I do not get a good test on the insulation test. When testing through the ECU plug, do you need a ground jumper? Thanks.

Yes, have wait till I get a gauge, until then I'll look other places. Aftermarket pump installed with the rest of the fuel system components.

Forgot to add, I couldnt get a the TPS insulator check to pass either out on the TPS sensor. So I guess the TPS is bad. AFM is clean and shinny like its 1982.

I replaced the EGR with a new one. Kept the old one, so I'll give it a go.

Only under load. I have not looked under the AFM cap, might go out now and do that. When I mentioned AFM before in my last post, I meant FSM. I use AFM at work, so I just flowed out. The AFM is under constant motion right, always making corrections. I was thinking it was something that was consistent, no what I mean?

Did the clamp trick, no change. I got the resister in from ZDepot, but will hold off an that until I do more testing.

I went through fuel system, but it could be that something dislodged. Car sat for many years, and fuel system was completely taken apart. Only thing original are the fuel lines under the car, which I blew out pretty good with air and gas.

Testing TPS. Continuity checks good at the TPS, Idle and full throttle. but at the ECU plug test as set forth by AFM, I get nothing. PIN's are PIN's correct, I dont need a year specific test for the 82 do I? Tried the clamp method on the return fuel line, no change. Did notice if I moderate the gas pedal (wiggle my foot) up towards full throttle, it does "seem" like it wants to accelerate smooth, but it may be my imagination. This was done without the clamp. All this done with the advance plugged.

Plugged advance inlet, cleaned TPS connection. No change. I go back through the fuel system and I'll start looking at the FSM for testing components. Thanks guys.

OK, so I read Zeds post about when the VA operates, and I hear what your saying. So lets talk about what the car is doing in a little more detail then. Starting from a red light, you accelerate normally until about high 2000's RPM an then a hesitation sets in running through each gear at around this RPM range. In 3rd, 4th gear, you can stand on the gas peddle and the car just acts as if you are disconnecting a plug wire or two, or grounding out, and will do this until you let off the gas, with anemic acceleration. New plug wires, plugs, and they are routed as to not ground out on anything, because at first thats what I thought it was. I guess I was hoping for an easy fix. If you get on the highway, 70 MPH for example, it cruises fine. New gas tank (NOS) from a donor car, fuel pump, filter, lines (engine bay only), fuel rail, injectors. New EGR(manual transmission), 02 sensor, PCV, cap, rotor. New battery, Hitachi alternator (overhauled), New belts. I have been through the wiring harness at all the plugs around the engine hoping for some corrosion, but nothing really notable. About 25 years ago, I had an 81NA, and it did this sort of thing but 10 times worse, and it was the AFM. I have not done anything with this car regarding the AFM. Thanks for all the replies. Added a few pics, just for SAG's. Driver seat is the only thing really bad with interior, everything else was nice. A tiny hairline crack in dash, thats it.

At work, I work overseas, so nothing new to add. My advance doesn't move period, its like sucking on a soda straw, just air. I'll plug it at first chance to see if there's a change. Resistor will be here next week. May be able to get to the car Thursday, maybe.....