Hey guys,
So me and my dad finally started to fiddle with the car today after it has been sitting for 7 years in the garage. We drained the tank of the old gas and filled it up with fresh gas,then we put a new battery in it and changed the oil and filter along with the plugs. We cranked the engine over and to our surprise it started right up but it was running really rich and blowing black smoke it then would die as soon as a little throttle was applied then we would try to start it up again and it wouldn't even fire it and we could smell that it was flooding. We pulled the plugs and they were soaking wet We then checked for spark and it seemed that the spark was yellow. We put the plugs back in and it will not fire we then let it sit overnight and if fired right up again but it died again when the throttle was applied. We are stumped could it be sticking injectors? or the fuel pressure regulator? and for the bad spark maybe the coil is shot?
Please help us!!!!
Andrew

 

welcome, and im sure someone will be able to help you out here, but my two cents are start with basics air fuel and spark, but i advise to start off by getting the user manual and checking timing on the car then start cleaning connectors and make sure you do a proper tune up, meaning if you need new spark plugs, distributor rotor, gas filter and such do so. but to me it might be your Air Flow Meter that is not right and or the air regulator then again its hard to say with out more info on the car and further explanation on the issues. good luck and download the service manual, or look for more info using the search tab on the site. good luck bro and im sure people here would not mind helping out

 

If you had it running, I would think its the injectors.

 

Im starting to think its the injectors too or the cold start valve? its literally dumping gas into the cylinders so i thinking it could be the fuel pressure reg along with the injectors maybe. I have no clue though

 

There is no cold start valve on the turbo motor. I suggest checking your CHTS and connection.

 

[QUOTE=NismoPick;305453]There is no cold start valve on the turbo motor. I suggest checking your CHTS and connection.[/QUOT

Yes thats right i got mixed up. Anyway me and my dad were working on the car today and we decided to pull the fuel rail along with the injectors. The injectors were very dirty and gumed up so we decided to test them out off the manifold. We turned the ignition to on to prime the rail to check for leaking injectors there were none. We then cranked the engine over and the spray pattern was so heavy! it was shooting fuel out like crazy definitely way too much. The injectors are going out tomorrow to an injector shop and they will flow bench them and clean them up. If this does not work im sure you will be hearing from me.

 

Ok so we got the injectors back and we installed them and fired her up. She runs a lot better but we are still having major problems. When it was still cold it will rev up nice but then we let it warm up some more and if we hit the gas it would try to stall we don't have the airbox connected so I put my hand over the intake were the little flap is (airflow meter) and then it would rev up but if I take my hand away it will stall when we try to rev it. It then did stall and then it would not start again it flooded right away. Any ideas?
Andrew

 

Bump Please help!!

 

update had the injectors flow benched and cleaned car starts instantly when cold will not or even fire after it has been warmed up even though there is spark, just noticed by removing the vacuum hose to the fuel pressure regulator it smoothed out the idle a little but still rough, if you put your finger over the vacuum nipple on the manifold it returns to running rough. Also note even the slightest touch of the throttle will cause the engine to stall and not start back up until it sits overnight. Also we disconnected the water temp sensor and the small head temp sensor? above it did not change the way it was running at all. Here is a link for a video of what it sounds like running.
Please help us!!!
Andrew

http://www.youtube.com/watch?v=z-LyQ...1&feature=plcp

 

Merged w/ your previous thread on the same issue, so we don't have to play the guessing game.

 

Thanks Nismo any ideas?

 

The chts like nismo said and O2 sensors can cause q rich state. Go through and clean all major electrical contacts. Also there should be ways to test each sensor in the fsm.

 

Ok thanks! i will check out the chts after doing some research i am pretty confident this is the issue.

 

Pretty good idea, since I said that about a month ago.

If there is spark, then there is no fuel... gotta find the sensor that's making the ecu not spray the injectors... AFM and CHTS are the two main sensors for that.

 

also very common is loose connector leads on the ECU plugs. typically though that doesn't prevent the car from starting, just makes it run horribly. When my turbo 260Z had a CHTS issue, it would run good but rich so when hot if it idled to long it would die, then no restart until after sitting for at least 10 mins. New CHTS and cleaned the plug and never had a flooding issue again.

 

OK so i tested the CHTS from the ecu pin and to body ground and it was showing open with no continuity so i look under the hood and to me and my dads surprise the plug that is supposed to go to the CHTS was just hanging there not connected so we start looking for the CHTS and its not there.... we then saw the threaded hole were it is supposed to be so we figure that 15 years ago when my dad sent the head out to be ported and polished he either removed it or the shop did and it never go put back. Another thing that concerned me is that i thought there should be coolant coming from that hole? Maybe someone can tell me. so we are ordering the new CHTS and hopefully that will be then end of the flooding issues.

 

Double check the thermostat housing to see if the CHTS is located there (maybe someone swapped in the pre-81 efi?).

But no, no coolant will come out of the CHTS port. It's closed off.

 

ok great and i dont think it could have been swapped because my dad bought it new in 82 and never touched it. Btw i am having trouble on the phone with nissan trying to get the CHTS they say they dont have a listing for a cylinder head temp sensor. Is it called something else?
thanks

 

Yeah, Nissan has two names for it, and now-a-days only uses "Coolant temp sensor". You can probably get it cheaper at Autozone.

http://nissan4u.com/parts/280zx/us_s...llustration_1/

http://www.courtesyparts.com/cyl-temp-p-280056.html

#16:

 

Thanks Nismo for all your help.
Andrew

 

Ok we just replaced the CHTS and and it started to idle really low at about 300 rpm and it would stall and backfire through the intake but the only difference is it would restart after it would stall were as before it would flood right away. with it running we disconnected the CHTS and the revs would pick up and it would run rich like it did before we noticed that the distributor bolts were very loose and we thought maybe it had been moved a bit throughing the timing off.I heard that maybe the ecu needs to be reset and the timing needs to be re done according to ThaPimpShrimp in his video below.
Please help!

http://www.youtube.com/watch?v=m5F5Q...endscreen&NR=1

 

Did you check all the wires for continuity to the ECU from the CHTS? I've found problems in the little harness from the sensor to the main harness.

 

Yes i checked the continuity from the harness were it connects to the ecu and to were it connects the the CHTS.BUT this is were it gets weird the fsm says check pin 23 at the harness and body ground and it says the resistance should be 2.1k ohm and im getting an open but when i check the continuity from the wire that goes into the ecu and the clip were it connects to the chts it shows continuity im stumped bad ground?

 

It's possible you got a bad sensor. Have you checked the fuel pressure? If for some reason the pressure is high it will run rich too.

 

Its weird because i got a resistance spec when i measured the resistance from the sensor and then i made sure that the wire from the the ecu harness to the chts was good which it was but with it connected i could not get a reading but the fsm say i should get a resistance spec.