96 nissan CG10 hot start flooding

pdc1, Jul 28, 11:34am
Running otherwise not too bad, it has suddenly developed hard hot starts. It appears to be flooding.
I've never had anything to do with petrol injectors, but I suspect maybe they are not seating and leaking!
What's the normal way of checking for this, would an injector cleaner additive work, what are the solutions otherwise, replace, recondition or.
Where is the normal place you would go to get the injectors serviced!
Cheers

the-lada-dude, Jul 28, 9:08pm
i suspectyour suppostion is suspect !highly unlikely.1st port of call is sparking plugs and doggy h / t leads or electronic component in the ignition system that fails when heat soakedI E :stopped when engine is hot and the excess heat invades the faulty component.OOORRRRR it could be something totally different, in which case i'll claim ignorance, and mental instability!good luck .

pdc1, Jul 28, 10:05pm
thanks, I like the heat soak theory, but it also does it when it is slightly warm. There is no other symptoms of a failing ignition once the engine clears, usually within about 5 seconds after start up, the engine runs sweet again, and there is no missing or anything.
The exhaust smoke on start up is black, and it stinks of unburnt fuel.
If it is a heat sink problem causing an component failure, would the item cool within 5 seconds to allow the engine to run again normally!

carmedic, Jul 28, 10:28pm
They're a bit prone to flooding when the plugs get worn, check the plugs and gaps first.

pdc1, Jul 28, 10:51pm
Thanks car medic, will do. haven't started to check anything yet. Just seems an odd problem to me with the problem, starting suddenly.
Yesterday I thought I would check the fault codes, and they came up clear, but the car was super flooded after. It took about 15 seconds of winding to fire up c.f. to about 5 seconds that it has developed this week. It has always started on the first compression always over the last 10 years.
The reason I started to think about injectors was that while checking the fault codes (they were 55 - clear) the key/ignition was on for a minute or 2. Is this a coincidence that it flooded worse then, or is injector leak a possible/impossible reason! I notice that the intake manifold sweeps down before the injectors which would allow the fuel to pool in the bottom of the manifold I guess. Just don't want to go pulling things apart unnecessary to check if I'm off base.

bigfatmat1, Jul 28, 11:32pm
slow cranking speeds from various causes and worn plugs are the biggest causes on nissans for flooding.

the-lada-dude, Jul 29, 12:48am
do the easy stuff 1st sonny.

pdc1, Jul 31, 7:28am
Ok, it cranks quickly. Changed spark plugs etc. Ended up removing the fuel rail with injectors in it, and have found one injector is dripping when you turn the key on, so I think this is the problem.
I went to the wreckers and got a complete set with fuel rail. They look exceptionally clean, and the wrecker said they were off a known running low mileage engine.
I put it all back together but it won't go. I swapped my original injectors into the new fuel rail one by one, and found that the engine would run, but only on the original injectors. e.g. if I had 3 old ones and 1 replacement, it will run on the 3 cylinders but not on the replacement injector cylinder if you get what i mean.
The injectors look the same, same color, size, plug etc - they are A46-H02 injectors. Old ones have 4 stamped into them. New ones have 5 stamped.
I haven't got a multimeter to test resistance.
What things do I have to check/know why these replacement injectors won't work!

pdc1, Jul 31, 8:22am
I now know that the resistance across the injector coil is the same as the original (11.3)

bigfatmat1, Jul 31, 8:46am
Well you have proved the injectors that you got from the wreckers don't work or incorrect so you need to get the correct ones.

bigfatmat1, Jul 31, 8:48am
still personally do not see one dripping injector causing the problem you describe, I have been wrong before however. Stranger things have also occured. Good luck

mugenb20b, Jul 31, 8:55am
Coolant temp. sensor faulty!

pdc1, Jul 31, 10:17am
In the weekend I checked the coolant temp sensor, and got a reading of 2500 ohms cold, and 300 ohms hot, so I think this is ok!
Just got me beat why the other injectors don't work in my engine. They look and measure identical, and the general clean newish look of them makes it hard to believe that they all don't work.

llortmt, Jul 31, 10:35am
They have a different part number, measuring resistance and comparing it will tell you nothing about their fuel delivery capabilities. One leaking injector wont cause no starting, it will cause a misfire and low compression on that cylinder.

pdc1, Jul 31, 11:16am
ok I have pretty much come to the same conclusion that the part no is obviously highly critical. What I hadn't expected was not being able to get the cylinder with the replacement injector(s) to fire at all. I've put my old injectors back in for now. The thing runs fine. It's just the starts that is the issue.

In my case if the injector leaks after you turn it off, the fuel will drain to the bottom of the intake manifold. It doesn't drain into the head inlet port by its design. However I have taken it on board that this is not likely the problem.
Cheers

motorboy2011, Jul 31, 10:16pm
please explain how it will cause low comp.

pdc1, Jul 31, 10:46pm
It washes the oil from the bores and rings, and then the rings aren't as effective doing their job

pdc1, Aug 2, 2:31am
Update - all sorted now. Replacement injectors had stuck needles in them. Compressed air in the nozzle end and tapping the injector until they started to hiss out the inlet has solved the problem.
I've replaced only the leaking injector at this stage. I'll do the rest later, but it has fixed my starting issue.
Thanks for everyones help. Cheers