1979 280 ZX troubling fuel? / air problem...... HELP PLEASE

[Guest dpiatkin]

problem on my 1979 280zx..... just installed a new stereo and in the process I shorted out the alternator(arc'ed across some stuff or some such thing). Anyway, replaced the alternator and starter solenoid(got that too)ran fine till belt on alternator came off due to wear and overtightening( my bad).... anyways replaced all of the belts and properly tensioned etc.. started engine and now it runs like cr#p !!!

It now idles at around 550 rpms and is running very rich and wants to stall. Also very hard too rev without bogging engine,but once up in the rpm range revs very well...... It has no power when placed in gear... Also blowing black particulate exhaust out the tail pipe !!

Help, is this a bad or stuck air flow meter or a blown head gasket or WHAT ?????? Please help folks !!

[Cruez]

Sounds like something electrical is fried... or a fuse..

 

Could have done something to the AFM or the computer...

 

Check all your fuses and fuse links.. That one may be hard to diagnose..

[Guest dpiatkin]

well the electrical seems fine now that the new starter and alternator are in. The headlights work well and do not sloww the engine RPMs... all of the gauges and lights on the interior work as well.... the car starts Right away, virtualy no starter cranking before it catches and starts running...

It would seem only the RPMs and exhaust are affected ??? maybe a stuck valve ????? not real sure

could be the computer, but I dont think that a 1979 has one ...??? Only a ICU unit on the distributor ( I think ??) no real ECU.....

I really hope that it is not my whole electrical system !!!!

does anyone know how to check a air flow meter ?? my cr#ppy chilton manual, is a "POS"... and does not give any testing or trouble shooting for the Air Flow Meter........

THANKYOU FOR YOUR RESPONSE AND HELP !!! PLEASE SEND MORE......

Seriously, thanks for your help and insight !

[Cruez]

What is it doing now?

 

75 and up Z's have a computer..its behind the panel at your feet in front of your door.

[Guest dpiatkin]

well it seems that the black sooty exhaust has 90 % stopped and now it is just running very rich !!!! the AFM is okay, and I cannot find any O2 sensor on my ehaust or manifold.........

It has very little power in the low RPM''s but picks up just about to normal around 3500 on up to red line... After a few minutes of driving it starts to die at low RPM's even with the clutch engaged. After it dies it becomes increasingly harder to get it to start or move in gear....

PLEASE HELP US ??!!!! I dont have the cash for a 302 swap right now ! LOL

[datsunlover]

Well, my 75 280z did the same thing.... you say the Air Flow Meter is fine? Are you sure? I have the Datsun factory shop manual and it gives a detailed list of checks to run on the air flow meter. Resistance readings and such. Also, if the flap inside has been bent (from the backfiring) it will not read properly and confuse the computer. I have talked to an older Nissan guy (used to be a mechanic when these cars were 3-5 years old) and he says that 90% of these type of problems are caused by a faulty/damaged Air flow meter. And your car may not have an O2 sensor (mine doesnt) so if you cant find it, don't be too alarmed! If you cant find the factory repair book, I think I have one somewhere that I could scan.. let me know.

[Guest dpiatkin]

that would be fantastic if you could scan those pages concerning the AFM... I have a cr#ppy chiltons manuel for the Z and it covers very little on the AFM( also very little on the computer or IC unit on the distributor, or anything else for that matter...) but I will double check the OHMs etc. concerning the AFM. Maybe you have better information for testing than I do ( wouldnt be hard).

Anyway, thanks for the post and the offer for scanning me those sheets!! I really appreciate it. If you could e-mail them to me it would be very helpful !!

Dang engine swap for a 302 sounds better all the time !! ZOOM ! lol

[datsunlover]

Ok, well I'll look for the pages. They are kinda hard to find/read, cause it's translated (BADLY) from Japanese, but it does have the required Ohm's readings and such. Keep in mind mine is a 75, but like I said (as far as I know) the only major difference is the two pins my car needs for the fuel cut-off switch. I checked the unit I am using righ now (80-83 ZX AFM) and the resistance readings were very close to what my book (75' Z) said they should be. I'll try to get them off to you this week sometime. Hang in there man!

[Guest dpiatkin]

I'll be waiting...... THANKYOU !!

[datsunlover]

ok man, check your mail.. if have sent you some info. (I think!) just wanted to make sure you got it. Let me know.