240ADAM Posted September 5, 2009 Report Share Posted September 5, 2009 So I have L28 turbo with Z31 computer and a ka throttle body. Its run pretty rich since the get go when I rebuilt it and dropped it in my S30. I put a new 02 sensor on and its still puffin some major black smoke, shitty gas milage too. Any way to lean it out? Ideas? Quote Link to comment
MAG58 Posted September 6, 2009 Report Share Posted September 6, 2009 When Did this start? Has anyone touched the AFM, and does it do it only at certain RPMs, or throughout the rev range? Stock Injectors, I'm assuming? I didn't know they flowed enough to make the Z smoke... Quote Link to comment
240ADAM Posted September 6, 2009 Author Report Share Posted September 6, 2009 Well I have a MAS on it from the Z31 and yes stock injectors. It really blows black in the morning, but thats probly cause its cold. When I pull up to a light or something I see a cloud of black smoke go past me and while driving i just smell the richness. I also dont have any extras on my intake manifold I stripped it bare. Quote Link to comment
Cuts metal like mad Posted September 6, 2009 Report Share Posted September 6, 2009 I would suspect that the injectors for a vg30et are larger than those for a L28et, SO if the computer thinks it is running the larger injectors and triggering them at the duty cycle appropriate for the larger injectors when running a smaller injector, you'd have a very rich condition. :D Make sense? Quote Link to comment
240ADAM Posted September 6, 2009 Author Report Share Posted September 6, 2009 Yes I do have Z31 injectors in, but from what I understand they are the same size as L28ET. Quote Link to comment
DRIVEN Posted September 6, 2009 Report Share Posted September 6, 2009 I'm by no means a Nissan expert but with any EFI application that has a continuous rich-run condition I usually start by verifying that the coolant temp sensor is within range. Also check your ECM and engine grounds. Quote Link to comment
MAG58 Posted September 6, 2009 Report Share Posted September 6, 2009 I would suspect that the injectors for a vg30et are larger than those for a L28et, SO if the computer thinks it is running the larger injectors and triggering them at the duty cycle appropriate for the larger injectors when running a smaller injector, you'd have a very rich condition. :D Make sense? I don't think it makes sense. If a car needs x grams of fuel/cyl to maintain stoic, it would throw out a duty cycle of xx to do that with it's stock injectors. However, when you move to a smaller injector your duty cycle would go up, however it would still be firing the duty cycle for the larger injectors, giving it a lean run condition? Quote Link to comment
hughdogz Posted September 6, 2009 Report Share Posted September 6, 2009 (edited) ^^^ I was going to say the same thing :rolleyes: As already mentioned, I'd check the coolant temp sensor (or cylinder head temp sensor). Fuel enrichment also reads the air temp sensor. What is your fuel pressure at idle? Is it higher than 36 psi with the vacuum reference unplugged? Dirty connections causing extra resistance at the MAF(MAS? I'm not too familiar with the Z31) Is the throttle position sensor set correctly? You probably already checked for a dirty air filter...that's all I can think of right now. [Edit: Plus, you'd think that using an ECU (& injectors) for a 3 liter in a 2.8 would make it run ~7% richer, but that's not much] Edited September 7, 2009 by hughdogz Quote Link to comment
Cuts metal like mad Posted September 6, 2009 Report Share Posted September 6, 2009 DOH! Well I knew that, but I guess my brain sharted last night... :blink: Oh well, can't get them all. Quote Link to comment
Bleach Posted September 7, 2009 Report Share Posted September 7, 2009 You could look up what makes a Z31 run rich. I think they always talk about the CHTS going bad but I don't hear that on the 280ZX so much. Check the plug and clean it good on the Cylinder Head Temp Sensor. Also, those MAS sensors don't always work good. I have two actually. I'm not looking to sell them but maybe I can stop by with them sometime and we can plug them in just to see if you notice an immediate results. Quote Link to comment
Icehouse Posted September 7, 2009 Report Share Posted September 7, 2009 Have you checked the ECU to see if it's flashing any error codes? It's worth a shot. I like the faulty MAF idea, the temp sensor would also cause a rich condition if it was bad. Quote Link to comment
DRIVEN Posted September 16, 2009 Report Share Posted September 16, 2009 Update? Quote Link to comment
nismopu Posted September 16, 2009 Report Share Posted September 16, 2009 (edited) Clean the MAF and run the coolant temp sensor for the 92-95 nissan pathfinder. Its the correct OHM rating for the factory CHTS that the 84-87 ECU's look for. Any of the later ECU's could care less about the CHTS. Also, if you haven't already; try using the blow through setup by putting the MAF after the turbo for a much better and responsive setup. peace. Edited September 16, 2009 by nismopu Quote Link to comment
datzenmike Posted September 16, 2009 Report Share Posted September 16, 2009 Is this the MAS that has the flap door? Quote Link to comment
nismopu Posted September 16, 2009 Report Share Posted September 16, 2009 Should be a MAF non trap door style, I am positive you have to run the z31 MAF for this efi system to work. Quote Link to comment
lynchfourtwenty Posted September 16, 2009 Report Share Posted September 16, 2009 you also need to use the little disc thing thats in the z31 distributor.. didnt see anything about u using it so ya.. put one in an try it out.. Quote Link to comment
240ADAM Posted September 16, 2009 Author Report Share Posted September 16, 2009 I haven't fix it yet it still runs rich, and yes I do have the chopper wheel in it. The MAS does not have a door on it, its the type with the sensor in the middle. I'm going to take the MAS off and clean it. Hope it helps. Quote Link to comment
datzenmike Posted September 16, 2009 Report Share Posted September 16, 2009 Pull the plugs... is one cylinder running rich and causing all the smoke? Quote Link to comment
240ADAM Posted September 17, 2009 Author Report Share Posted September 17, 2009 That's a good idea, ill check that out today. Quote Link to comment
zedman Posted September 17, 2009 Report Share Posted September 17, 2009 Hey, do you have a write up on your L28ET swap into your S30 ? I'm going to be doing the same thing this winter, have all the bits, ECU, etc, just wondering about some of the wiring ? Cheers Quote Link to comment
72240z Posted September 17, 2009 Report Share Posted September 17, 2009 There's write ups on hbz and zcar Quote Link to comment
zedman Posted September 17, 2009 Report Share Posted September 17, 2009 Hey thanks very much, my search skills are the sh*ts, I've searched hybridz, etc, never came up with anything ! I know it's off topic, but thanks for the info ! Cheers Quote Link to comment
Skib Posted September 17, 2009 Report Share Posted September 17, 2009 Hey thanks very much, my search skills are the sh*ts, I've searched hybridz, etc, never came up with anything !I know it's off topic, but thanks for the info ! Cheers really? its like the most covered/common S30 swap..... like, ever :mellow: Quote Link to comment
hughdogz Posted September 17, 2009 Report Share Posted September 17, 2009 Isn't it a sticky on in the turbo section of HBZ? No searching necessary... Quote Link to comment
Skib Posted September 17, 2009 Report Share Posted September 17, 2009 Isn't it a sticky on in the turbo section of HBZ? No searching necessary... theres even a thread on page 1 of the FAQ Quote Link to comment
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