Nissan noob question - thinking of selling due to problems

[RexSiChic]

I'll be as brief as I can here. I purchased a 90 240 w/a 93 KA24DE in it a few months back. The previous owner had just rebuilt it, was building it for the 1/4 mile, and was focused on removing emissions and weight reduction. In doing so, he deleted a LOT of things off the harness, including having nothing plugged into the TPS. The car ran pretty good at first, but slowly ran worse and worse, as if it were missing out and had a lack of power. 1 day while driving for a few hours, it started running really bad, backfiring, and the temperature eventually went completely cold. Once shut off, it wouldn't start, until we replaced plugs & wires. It had dumped fuel into cylinder #3. It ran as good as I can expect from her for awhile, but then did the #3 cylinder nonsense again, but no change in temp. I replaced plugs 2 more times, ran fine for 1 day, now it won't even stay running without giving it gas. Moral of the story is, idle sucks, backfiring, it's no longer dumping fuel, now the plugs show it's running lean...and I'm ready to get rid of it just due to all the hassle. I've been wondering if it's a timing issue, is it due to all this stuff deleted off the harness, bad MAF...I just don't want to sink a lot of money into it at this point. Any help is appreciated!!!

[carmo]

Wow! Sounds like you got your hands full. It almost seems that the number 3 injector was getting stuck open. You should try replacing the engine harness if its all cut up. You have got to have some kind of TPS input to the ECU. If the guy just clipped all the connectors he didn't use then some of the bare copper could be touching causing issues and possibly smoke testing the ECM. Is there even a check engine light bulb in the dash? If there is its probly burned out by now. Unfortunately you may need to fillet the harness open and see what dumbass did. Goodluck

[RexSiChic]

check engine light DOES work, as it comes on briefly at start up, but it hasn't thrown any codes. This is my first Nissan, I've been doing Honda's for sometime now. Is there any chance Nissan's do the same on the ecu with the flashing red light? Im hoping to check the timing this weekend, although at this point, the only person I have willing to help me out with it doesn't know Nissans either. I was trying to locate a write up somewhere of basic timing checks & adjustments, but couldnt

[mmaxeyjr]

http://www.240sxtech.com/

[RexSiChic]

Thank you. That's 1 webpage I didn't locate in my search. However, can I follow normal timing instructions since there is nothing on my harness to even attach to the TPS?

[carmo]

Maybe theres something out there I don't know about but you have got to have your TPS plugged in. Try to locate the cut wires, get yourself a connector from a junk yard and splice that bad boy in. TPS Throttle Position Sensor tells the computer how far the throttle plate is open and how fast it got that far open. This is vital information for the computer to tune fuel and ignition timing. I say start there and then move on to the next issue. You also need a Mass air flow sensor unless the car has been converted to speed density/ MAP sensor.

[RexSiChic]

Over the weekend, found the TPS is hardwired from the previous owner who did this rebuild. The timing had been advanced as far as possible on the distributer, so we got it timed and it was running perfect until we turned it off, then restarted it and it was back to the way it was before. I know the previous owner had planned on turbo, so now Im wondering if it has bigger injectors in it because of that??? I also changed out the fuel filter & the gas that came out of it was filthy. Next step is changing injectors if I can find some cheap, stock ones. Once trying to figure this problem out becomes pricey, Im giving up and selling it.

[carmo]

Hang in there. When runs like poopy, is it dumping black smoke out the tail pipe? Does the ECU look like its been messed with, like someone tuned it. Any goofy wires at the ECU harness? Check all your vital sensors/ ECU inputs. MAF sensor, coolant temp sensor, TPS. I've seen bad distributors work off and on and cause some crazy drivability issues.

[RexSiChic]

TPS is hardwired, there's a LOT of stuff deleted off this harness under the hood, unfortunately. I have a new MAF, injectors & fuel rail coming, so we will see if any of them help. Thanks for all the input everyone!!!