KFD Posted June 22, 2013 Report Share Posted June 22, 2013 Alright guys... Instead of polluting the forum with different threads, I'll just make one thread for my car. I found this thing for my buddy Bobby on Craigslist a month or so before our deployment was over last year. We got back stateside, and he bought it. I taught him how to drive stick in it. It started giving him issues. Then the car sat, and sat... He calls me up about a month ago with the words "Hey, do you want to buy this thing?" What would you guys do!? So, $1500 bought me a Z that misfires, has a radio that resets when the brake is applied, and creaks and groans when I turn, or go up driveways. Oh yeah, and it overheats... One of the first things I did was put a thermostat in the car. It didn't have one. It doesn't run as hot. Woo-hoo. Next was a coolant flush, then the weak fan clutch was replaced, and while I was at it, the waterpump, even though it looked fairly recent, was replaced. The overheating issue was tackled. Next up was the charging issue, that radio, and that damn lamp (as in house lamp you plug in the wall) switch. When I was chasing down short-cutted leads on that radio, I found a really nifty lamp switch. Combined with the funny relay-like clicking coming from under the passenger seat, and the car's battery being dead, I started reading on here and Hybrids to figure out what a common current draw issue could be, and why this short-cutted switch was here to begin with, (turn the switch, and the car stops) and my assumption was a fuel-pump cut-off. Made sense to me. I chased the wires down, and it's not even connected to the fuel pump! Turns out, this was a simple kill switch, rigged in series between the coil and ballast resistor. Slick. The relay rattle under the seat? That funny little relay was held on loosely by one screw. Took out the volt meter, and checked that I-just-put-in alternator. It was 15 or 17 volts, don't remember. The battery? 12.3 volts, when the car was running. Damn. Chased down some wires, cleaned connections, nothing. Fixed a ground wire connector at the alternator, still nothing. Ordered a voltage regulator (either doing a ZX Interal Reg or Monaco/Premier Delco conversion) for now, wifey is getting tired of a parepetual battery and battery charger on her porch. Fingers are crossed this will fix the charging issue... The last part, where we are today, is the Fuel Injection. I downloaded the FI Bible, and have been studying this thing like crazy, before you ask... A misfire. It's driving me bonkers! Warm, cold, doesn't matter. It's a pop out of the intake, loss of power, then over 2500 or so, it's back on like Donkey Kong! This thing is also running rich, and getting sub 14 MPG. Unplugged the Thermotine, Coolant Temp and the Cold Start Injector at various times, (you should've seen me go bonkers when I had the Thermotine and CT connectors crossed!) and not much change. Cleaned the AFM, but haven't adjusted it yet. I haven't started on checking ohms/resistance at ECU, but that's next on the list. I just noticed there is a plug on the side of the thermostat housing where the EGR coolant sensor goes, I don't see any electrical connectors to the EGR yet. I am thinking about replacing that coolant temp sensor, but I don't want to haphazardly start replacing parts, especially this L-Jet system. So, instead of asking idiot questions that I can find by searching (and making 23423 threads,) I'll just start this thread. I honestly want to find a pre-smog 240Z shell (I am guessing that pesky creaking is due to body flex, given the less-than stellar shape of the framerails), and ultimately do an LA-Mopar swap. I'm a paint splotch and fendertag numbers guy when it comes to Mopars, and being that Japanese cars are my newest interest, finding a period-correct 340 to throw in a 240 (and make it look like it belonged there originally) would satisfy the Sports Car/Japanese Car/Mopar Muscle love. I eyed a nice four barrel intake on Ebay, considering I don't have smog for another year or so. I think the guy at the smog shop passed me just because it was Z... Later KFD Quote Link to comment
KFD Posted June 24, 2013 Author Report Share Posted June 24, 2013 Okay, so this is what's driving me crazy right now... It's not a turbo. It's erratically having loss of power. 500 RPM if I am lucky at WOT, misfiring through the intake. I'll pull the car over, then a few seconds later, it runs fine. I have a lose connector or ground somewhere... Turns out it's a loose connection somewhere. I'll make a right turn, then about 50 yards down the road, the car has no power. Incidentally, the dash lights peter out if I push the clutch in. Snap the clutch back out, and the motion of the car driving the wheels, and ultimately, the engine turning the alternator turns the dash lights back on, (but the headlights stay on regardless). This car's electrics! It seems nothing works unless the engine is running. I don't know why the constant +12v is wired through the ignition. Is that normal?? This vacuum line tees off the vacuum advance. I am guessing this is going to the diaphragm just out of frame? As you can see, the vacuum connector is broken off. I am pointing to another connector next to the Cold Start valve. I just cleaned that connector, is that operate a sensor/switch that's part of the EGR? This frayed ground wire is a very likely culprit to my issues. I was going to splice a new ground this weekend. The TPS contacts weren't stuck, contacts cleaned... That's the ghetto-rigged kill switch I am pointing to... I have the EFI bible, but between working like a madman and forgetting to grab a multimeter from work, I will get this misfire tackled. It doesn't behave like a timing issue (the car runs normally intermittently, runs rich..). I am not asking for a handout, but any advice would help! Do these nutjob symptoms seem familiar? It seems this damn thing misfires at all temperatures, so I don't think it's a coolant/thermotine issue. In fact, disconnecting these components make no difference.. *AFM *TPS *Cold Start/Termotine/Cold Start Injector *That diaphragm EGR thingy that's next to the CSI. It runs a little better... Flat after 5k. *disconnecting any fuel injector... I think I read injectors are batch-fired, so injector connectors don't have a particular firing order. 1500-3500 misfires, runs rough, much like every other "help my Z runs rough" thread on every other Z forum. Groan. I got a few ideas before I throw a Holley four barrel on it... Quote Link to comment
KFD Posted June 25, 2013 Author Report Share Posted June 25, 2013 Okay, so I figured the sporadic running was a battery connector that came loose after making spirited right turns... Cleaned the bullet connectors from the coolant temp sensor, and wow! Never seen the car run to redline so fast! Still gets stupid (flat spot, loss of power after 2k- ~3500 RPM. I think the AFM is the culprit... New issue... At high RPMs, the underseat relay goes nuts! I have no indication that the car is starving for fuel, but the clicking it makes corresponds with the "brake" and "charge" light flickering, and the voltmeter is spiking like crazy. I'm on the hunt! Quote Link to comment
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