onesexZcar78

oky doky thanks for your help we'll try again tonight hopefully we'll get it figured out...two and a half weeks without my z is driving me nuts! If we have no luck I'll be back

haha another stupid question...what does FSM stand for I've seen it a lot on here but am not familiar with the meaning. Thanks a bunch I won't try the other ECU no need to fry it.

Can you use an ECU from a 1980 280zx in a 1978 280z? I think my ECU is the base of a problem we're having with my car but I really don't want to have to buy a new one to find that mine is ok. So, we also have a 280zx that runs great and I was hoping we could plug that one in to see if it fixes the problem. Then I'd buy a new one. If not is there a way of testing an ECU to see if it is bad? We have access to all the tools a mechanic could ever ask for so if theres a tool or a way to test them or if they are interchangeable in those years please help me out! Just trying to eliminate things so anything is helpful thanks

We figured out what was wrong! Thank you to all who replied. It ended up being a bad AFM, a bad cold start valve, and a bad thermistor. Thanks again ~Kat

I have another question/concern that Joe was talking about yesterday when we were working on my car...he said that it had 12v on both sides of the injector plugs but it was supposed to drop some on one side. Does it drop after it starts or should we not have 12v on both sides? If we are not supposed to have 12v on both sides what may cause this? I read in another forum I was reading that it could be caused by a bad ECU? is this true?:surprised

I will also verify that we did get the correct gasket although I believe he checked it against the one we pulled off which was working just fine minus the exhaust leak which is why we decided to replace it.

Thank you very much for all your suggestions. We do have good/correct compression and fuel pressure. My fiance is a mechanic and has all the correct tools to check things like fuel pressure. There are however quite a few suggestions you gave me that we can try so again thank you very much. I will pass these ideas on to Joe(fiance) and with fingers crossed maybe one of them will be the problem. As far as electrical connectors I know we've replaced a few of them including the one to the coolant temp sensor and all the parts we did put on my car were not thrown on in hopes of fixing it they were parts that were not working properly and were replaced. If anyone else can add to Bo's list of things to check it's very much appreciated although we do have quite a list of new ideas to try now thanks to Bo.

We do have compression and everything is hooked up nice and tight. We also replaced the fuel pressure regulator for the specific intake we put on it. unfortunately I can't remember what year zx those parts came off of because we go them at a u-pull-it yard. What I was getting at with the idle adjustment screw was that it seems almost like it's idle is to low to start. Sounds wierd because how can it be too low to start but that's what it seems like to me.

Ok I just talked with Joe (fiance) and he put my '78 tps on the newer throttle body. He also said that the only difference between the two AFM is that the one from my 78 has a air temp sensor in it which he took out and put into the newer one...So, would all this end up working together? I also forgot to mention we have spark and fuel we've checked the plugs and wires both good and the new coolant temp sensor is for my 78. Any ideas on other things we can check? Could a coil cause this or maybe something in the ignition system? ~KatROFL:paranoid:

Thank you for your input. So, you said that the AMF isn't compatable with the 78 ECU? Is the tps also not compatable with the ECU? And out of curiosity if the intake matches up to the head just fine what problems would it cause being from a zx? I don't know enough about the specific parts I just know that the L28 was in both the 280z and the zx so other than different sensors I'm not sure what's different about the intake itself. Again thank you for any help you can provide us! :stupid:

Hello all, I own a 1978 280z with the stock L28...my fiance has replaced some parts recently and it seems to be getting worse...doesn't make sense to me. Don't get my wrong my fiance knows Z cars like the back of his hand but he's been kinda puzzled and very cold as we have no garage to work on it in. So here's what we did...had an oil leak and replaced the valve cover gasket, had an exhaust leak and replaced the intake/exhaust gasket. It also sounded like a subaru before we started...had a miss and replaced the #5 injector but we put this and all other injectors which are not even a year old into a different intake that we had wanted to try which is from a 280zx. With the new intake we also put the throttle body that came with it but left my mass airflow sensor. We got it all put back together and it started but idled around 1500-2000rpm! We realized that my MAFS was bad anyway so we replaced that with the one that came with the intake...fixed the idle and now it has a bad miss...so we replaced the injector plugs because they were old and crusty and coming apart...now it misses worse! So he thought about it and some how came up with coolant temp sensor? Replaced that and now it wont start at all. It turns over and fires every so often but no start. If you take the idle adjustment screw out it fires more but still no start??? Any ideas? Please help! Thanks, Kat

I know I'm new here and don't have very much knowledge to the indepth parts of my Z but I own a 78 280z and I've had the brake light stick on before...I have reason to belive it is associated with being a check engine light as well as a brake warning light. So, with that said is there anything else going on with your car? Just another idea to think about.:nervous: