MatMan Posted June 11, 2008 Share Posted June 11, 2008 First of all, if this thread should have been posted to the Announcement board, by all means, please move it. Now, the sad part. A good friend of mine is rightfully upset. His 86 N/A 300ZX could not pass smog, has lapsed on registration (it's payed, but DMV won't release stickers until proof of smog is shown) and yesterday his apartment complex informed him that they will have his car towed on Friday if he doesn't fix the situation. So, without further ado: http://sacramento.craigslist.org/car/715624547.html It's going cheap. Quote Link to comment Share on other sites More sharing options...
JMortensen Posted June 11, 2008 Share Posted June 11, 2008 Does he realize that in CA he's responsible for getting it to pass smog to transfer the title to the new owner? Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 11, 2008 Author Share Posted June 11, 2008 Yup. I believe he is hoping (sp?) someone would take pity on him and buy it to part it out, not for a street legal car. Quote Link to comment Share on other sites More sharing options...
Pete84 Posted June 12, 2008 Share Posted June 12, 2008 What happened to the ECM and sensors? Sounds kinda serious. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 12, 2008 Author Share Posted June 12, 2008 What happened to the ECM and sensors? Sounds kinda serious. I am not sure the EXACT story, I have heard bits and pieces of the saga for the last 3 months. This is what I have pieced together: The car began to run a little rough, but not so rough that it degraded the performance too badly. The registration was up a couple of months ago, and when the car was smogged, it failed. They (my friend and his wife) have been going back and forth about weather or not to try to get it so it would pass smog since then. The shop they took it to (I do not know which one, but since this couple are not really "car" people, I would have to assume it wasn't one with a super high Datsun/Nissan talent [read:the cheaper the better]) began with simple diagnoses: alternator (thought the internal regulator was faulty), fuel pump (thought that was not steady), cat, and now the shop thinks it must be the ECM. I want to tell them that they need a second opinion, but they really can't afford it. They were hoping for the "oh, it's this one part, and then it will work" fix. IF (I know, if is the biggest word in the English language) my wife would let me, I'd throw them a couple Benjamins and part the thing out at my place. She'd really like that!!! [edit] I have an 82 N/A ZX parts car, but I don't think the ECM would swap in...am I right?[/edit] Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 12, 2008 Author Share Posted June 12, 2008 Update - He is asking $1000, but HIGHLY motivated and willing to negotiate. This car is clean, inside and out. Quote Link to comment Share on other sites More sharing options...
Gollum Posted June 12, 2008 Share Posted June 12, 2008 [edit] I have an 82 N/A ZX parts car, but I don't think the ECM would swap in...am I right?[/edit] Correct, they're different. That said, I see Z31 cars around here all the time. I can pick them up a ECU (I always call it a ECU, but I think that's the ECM on the Z31) if they want me to. I think PNP only charges like $30 for a ECU. I'd suggest he finds someone's place to store it for the time being. I'd also suggest they find a place that's a "pass or don't pay" or a "pass or next test is free" type of a place. That way they can see if the work done is actually having an effect on the problem. If I saw the test results I might be able to give some good tips on how to get it to pass. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 14, 2008 Author Share Posted June 14, 2008 Thanks, Gollum! I have forwarded them your post, and I believe I will be scanning the test next week. Right now, the car is safe and sound on my property. At least they will have some peace of mind and not get hassled about getting towed. Might just pull her apart and replace the timing belt, water pump and tensioner while there, it's got about 215K on it, but I was told that it may have been rebuilt around 100K. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 18, 2008 Author Share Posted June 18, 2008 To all who replied, thanks for your help. Here is the smog results for the ZX. I hope this sheds some light. It looks (to my untrained eye) that the NO was the culprit at low speed. at high speed it was fine. ZX smog.pdf Quote Link to comment Share on other sites More sharing options...
Phantom Posted June 18, 2008 Share Posted June 18, 2008 Isn't NO primarily controlled by the catalytic converter? With 215K on the engine the converter could be all cruded up and non-functional. That would certaily be an easy fix. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 18, 2008 Author Share Posted June 18, 2008 I would agree. BUT the cat is new. I was thinking more along the lines of timing. 18* BTDC, and the mechanic said the ECU was faulty. We're going to find an ECU and swap that out and see where it goes from there. Quote Link to comment Share on other sites More sharing options...
Gollum Posted June 18, 2008 Share Posted June 18, 2008 CAT's DO affect NOx, but they weren't designed to. In fact when studying the subject with a SMOG REF the group concluded that there's in fact zero reason a cat should ever reduce NOX emissions, but in testing cars with and without it obviously does. So it's a side effect of cleaning the air that it happens to lower NOx. NOx. or NO on the test, is combustion heat. A high compression motor will fail on this easily. Majority of the time when cars are failing from NOx it's due to carbon build up in the chambers. Best thing I could recommend would be to run the tank nearly dry and then put about $15 worth of fuel injector cleaner in the tank. Then proceed to drive hard on the engine for an extended period of time. You want that engine to get hot and burn as much crap as possible off the inside, and the fuel you just added almost guarantees no knock issues. Anyone know any safe ways to clean the chamber out without removing the head? Maybe pouring something into the spark plug hole? Doesn't sound safe, but maybe someone's got some experience in this regard. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 19, 2008 Author Share Posted June 19, 2008 You think Sea Foam will work? http://forums.hybridz.org/showthread.php?t=135057&highlight=sea+foam Quote Link to comment Share on other sites More sharing options...
Gollum Posted June 19, 2008 Share Posted June 19, 2008 Yes, the sea foam stuff would be a great option to clean out the engine. Just make sure to put plenty of miles on the car afterwards as that stuff can take a while to get out. Quote Link to comment Share on other sites More sharing options...
woldson Posted June 19, 2008 Share Posted June 19, 2008 GROSS POLLUTER. In Washington state they just say pass and fail. Wonder who wrote that software?! Quote Link to comment Share on other sites More sharing options...
BillZ260 Posted June 19, 2008 Share Posted June 19, 2008 First off, I have a hard time with this story being all that SAD. It sounds more like LIFE to me. But anyway... Failed Smog Check? Financial assistance may be available... http://WWW.SMOGCHECK.CA.GOV 1-800-952-5210 Has your friend checked in to this? Could help pay for part of the repair bill? Quote Link to comment Share on other sites More sharing options...
Careless Posted June 20, 2008 Share Posted June 20, 2008 Yes, the sea foam stuff would be a great option to clean out the engine. Just make sure to put plenty of miles on the car afterwards as that stuff can take a while to get out. my car is still spewin some of that stuff. combined with some oil that i KNOW it stripped off the intake plenum walls because i see it coming out of the tailpipe, and there is no more oil in the plenum (stuck open pcv valve, DAMN YOU!) Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 30, 2008 Author Share Posted June 30, 2008 Here is a PDF of the retest took on Saturday. Failed again, BUT the NO went down almost 1000! HCs are up slightly. One of our more helpful members has gratiously pledged his time to look for an ECU for an 86 N/A 300ZX. Thanks Gollum!!! John, the owner of the car, tells me that the car hasn't run this well for over 5 years, so I am stepping in the right direction. I wish there was a "silver bullet" that would kill the problem. I know better. Besides the new stuff the "mechanic" changed out (CAT, alternator, FP), here is what I have done: Cleaned out AIV unit, replaced the vacuum dashppot on top of the AIV, Seafoam treatment in the fuel, oil and intake manifold and new NGK (as specified by NAPA) sparkplugs. The only things that I think are not new to the system are the EGR valve (which passed functionality test), the TPS, The O2 sensor and the ECU. When one changes the CAT, does one need to also swap out the O2 sensor? We'll see. ZX smog II.pdf Quote Link to comment Share on other sites More sharing options...
Gollum Posted June 30, 2008 Share Posted June 30, 2008 You don't NEED to change an O2 and a CAT at the same time, they're completely independant of eachother. But O2 sensors are recommended changing ever 30k miles, so that's about every other year for most people. They tend to be able to go a bit longer, but more than 50k is pushing it. Notice how the 25mph test passes is flying colors? Something is happening between 15mph and there. It might be the ECU going into closed loop and correcting the fuel mixture and activating the EGR. You're on the brink of solving it. I don't think it's going to be the ECU, but I'll still see if I can find one anyways. Quote Link to comment Share on other sites More sharing options...
MatMan Posted June 30, 2008 Author Share Posted June 30, 2008 I am almost POSITIVE the O2 hasn't been changed in 100K. I was thinking the same thing on the slow speed vs high speed readings. Well then, would that point to the TPS? As I understand them, the TPS has three settings: idle, partial throttle and full trottle. It gives the ECU different voltages for each setting, and the ECU them detrrmines mixture. Hmm. Quote Link to comment Share on other sites More sharing options...
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