# only one cyl firing on 240



## djandy (Aug 18, 2005)

Usually it starts on all 4, revs up then revs down and the cylinders start dying one by one, we changed the rotor cap and spark plugs but it didnt make much difference. When we take out the spark plugs of the cylinders that dont work they're full of gas so im guessing theres gas that gets to the engine.

What else can we check?


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## Panda Rox Ur Face (Dec 19, 2004)

djandy said:


> Usually it starts on all 4, revs up then revs down and the cylinders start dying one by one, we changed the rotor cap and spark plugs but it didnt make much difference. When we take out the spark plugs of the cylinders that dont work they're full of gas so im guessing theres gas that gets to the engine.
> 
> What else can we check?


This is interesting, I have never heard of something like this, although I had something similar, but nothing like this.

My problem was all traced back to a SMJ (Super Multi Junction - something Nissan came up with, sounds sweet, huh?) It was not connected completly, I unplugged it, then plugged it back, and BAM! Fuel pump came on, spark was had on ALL cylinders, and the car ran great since then. The connecter was on the passanger side, near the battery.

But your problem seems a little akward. I would make sure your coil is good, check your wires. Do you have a Digital Multi Meter? If so, you can check your wires. Put the Multi Meter on Ohms, and put one lead on one side of the plug wire and the other lead on the other side of the plug wire. There should be about .2 ohms of resistance. If more, or you get OFL, then the wires are bad. 
You can also check the resistance in your coil. Put one lead one the positive side of the coil, and the other lead on the negative, there should be VERY LITTLE resistance. Now put one lead on the power side, and the other lead to the output side (where the plug wire goes) and there should be A LOT OF RESISTANCE, due to the step up resister in the coil. 

When your testing for spark, do you have all the spark plugs out and grounded on the motor? If not, check that. Just take each spark plug out, connect the plug wires to them, set them on top of the motor and watch them while someone tries to crank the engine. See if all of them are getting the same spark.

Just respond back with any progress you make or any other questions you have.


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## djandy (Aug 18, 2005)

Yep, its seriously weird. We got the car free and well, its not in great shape but it's not so bad either, the engine probably hasn't run in a year or so. We checked the wire resistence a few days ago and if I remember correctly it was arround .5 or so for each wire, but the thing is, I tried each wire on that first cylinder and it worked with each wire. Im gonna check the coil, but the sparks seem to be fine on the coil, and we checked the sparks on the plugs aswel and the SEEM to be fine, I can't tell this is pretty much my first experience at this.

We did however, umm screw arround with the fuel system, we had to modify a pump from a different car to fit correctly in our tank(it was the pump we found installed(VERY BADLY) in the tank when we got the car, it wasn't sealed it had a shirt wrapped arround the edges as a gasket) but we're getting lots of pressure in the system and we fixed a leak too.

Im pretty doubtful that its because of a compression problem since it starts at times. Tomorrow morning we're going to try to take apart the fuel rail and look at the injectors, check to see if they're clogged or something, seeing as how we couldn't find the repair manual ANYWHERE in town, we have to order it off the internet and it's probably going to take up to 2 weeks to get. And we're starting school next week....

Is there anything we should know before going intoo the fuel rail/injectors?

any help appreciated..
andy
and cris...


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## ZooYork (Jun 23, 2004)

u got that gas in there cauz ure plugs arent fireing, lookinto why the plugs arent fireing first.

does it idle at all?


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## djandy (Aug 18, 2005)

Ok well, we're pretty sure we need new wires because some of them have over 1k ohms and the coil-distributor wire has arround 13k, what's the normal resistance on these? 

We took off the fuel rail & injectors and we're cleaning them, on the part connected to the rail on the injector there was, well, it was clogged with a mixture or rust and gas or I don't know wtf it was. I think it's gonna work way better after we reinstall it and get new wires..

Any thoughts?


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## Panda Rox Ur Face (Dec 19, 2004)

djandy said:


> Ok well, we're pretty sure we need new wires because some of them have over 1k ohms and the coil-distributor wire has arround 13k, what's the normal resistance on these?
> 
> We took off the fuel rail & injectors and we're cleaning them, on the part connected to the rail on the injector there was, well, it was clogged with a mixture or rust and gas or I don't know wtf it was. I think it's gonna work way better after we reinstall it and get new wires..
> 
> Any thoughts?


while you have the plugs and rail out, disable the fuel system, (unplug the fuel pump from inside the trunk) and crank the engine a bunch of times. You want to do this to make sure you don't flood the engine! If you try cranking a whole bunch of times, the injectors fire really rich to help ignite. Well, if your cylinders get filled with enough fuel, then your cylinders will not fire (you can compress air, but you CANNOT compress a liquid). So make sure your cylinders are nice and dry.

Do you have a friend with a 240? If so, have him/her come by and trade out parts that you have think are bad (coil, wires, if you have a timing gun, then maybe even the distributer, but make sure you KNOW what your doing). This may help you out a bunch, I know it helped me out of a tight spot once or twice!

Good luck


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## Zen31ZR (Mar 24, 2004)

If your cylinders get full of gas, you'll have a lot more problems than them just not firing. It's called _hydrolock_ and is pretty much guaranteed to bend rods and blow headgaskets.


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## djandy (Aug 18, 2005)

Now we're finally getting somewhere... We reinstalled the injectors after cleaning them and the car finally runs in all 4 nicely. There's a ticking noise, its probably one of the valves that isnt getting oil for some reason, we'll check that out soon... But then there's this other problem, when I rev it really high, it starts to give out smoke, what causes this? dead piston rings? 

I know the oil is REALLY REALLY old black and crappy, we're gonna change it first thing in the morning probably...


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## Hydrolock (Feb 18, 2005)

Zen31ZR said:


> If your cylinders get full of gas, you'll have a lot more problems than them just not firing. It's called _hydrolock_ and is pretty much guaranteed to bend rods and blow headgaskets.


If your cylinders are filled with gas than that car would not be running and your not going to bend much of anything trying to turn the car over. Either way it would wash the cylinder and it would end up in your oil pan.


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## dkdeleon (Jul 28, 2005)

the smoke you are seeing is from the gas in your oil from the cylinders,
change the oil and clean the pan.
as for the ticking noise ,is it ticking when you rev or all the time???
if it is ticking when you rev you need to change your rod bearings,
its a real simple job just take the pan off and you will see the rod end
caps remove caps and bearings and replace with new ones. do each rod one at a time.


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## djandy (Aug 18, 2005)

Okay, no more ticking, no more smoking. 

The rev seems to cut off at 4k though, maybe its because of my crappy wires and distributor cap. How do I tell if it's a ignition cut or a fuel cut?

Also, the fan seems to be direct with the engine, shouldn't i have some sort of clutch so it doesn't go so fast and... loud? My engine sounds like a freakin muscle car with that fan.


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## Hydrolock (Feb 18, 2005)

djandy said:


> Okay, no more ticking, no more smoking.
> 
> The rev seems to cut off at 4k though, maybe its because of my crappy wires and distributor cap. How do I tell if it's a ignition cut or a fuel cut?
> 
> Also, the fan seems to be direct with the engine, shouldn't i have some sort of clutch so it doesn't go so fast and... loud? My engine sounds like a freakin muscle car with that fan.


Put a fuel pressure gauge on it. Or get ghetto and rev it to where the problem first starts, and try to correct the problem with some propane gas. Crack the valve on a blowtorch and let the gas flow into the throttle body. If the car picks up your having a fuel related if it does nothing, you need to look for other causes. Propane has a very similar burn rate as gas.


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## djandy (Aug 18, 2005)

Hydrolock said:


> Put a fuel pressure gauge on it. Or get ghetto and rev it to where the problem first starts, and try to correct the problem with some propane gas. Crack the valve on a blowtorch and let the gas flow into the throttle body. If the car picks up your having a fuel related if it does nothing, you need to look for other causes. Propane has a very similar burn rate as gas.


Are you serious?? Is there another way to find out if its a electric of fuel problem?

What should the fuel pressure be at?


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## rogoman (Dec 16, 2004)

djandy said:


> Are you serious?? Is there another way to find out if its a electric of fuel problem?
> 
> What should the fuel pressure be at?


An easy way to test the fuel pump and filter is to disconnect the fuel hose from the top of the fuel filter and insert a long length of spare hose into the top of the fuel filter with the other end draped over the fender going into a catch can placed on the ground. Now turn the ignition key to the run position but DO NOT START THE ENGINE. You should see fuel going into the can at a good rate for several seconds.

The fuel pressure is 34 psi with the vacuum hose connected to the pressure regulator; 43 psi with the vacuum hose disconnected.


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## Hydrolock (Feb 18, 2005)

rogoman said:


> An easy way to test the fuel pump and filter is to disconnect the fuel hose from the top of the fuel filter and insert a long length of spare hose into the top of the fuel filter with the other end draped over the fender going into a catch can placed on the ground. Now turn the ignition key to the run position but DO NOT START THE ENGINE. You should see fuel going into the can at a good rate for several seconds.
> 
> The fuel pressure is 34 psi with the vacuum hose connected to the pressure regulator; 43 psi with the vacuum hose disconnected.


 Thats not going to show you much. The prime pulse pressure, and the system pressure while it is running are two entirly different things and one can happen independent of the other.
See if you can borrow a fuel pressure gauge from someone and a set a noid lights and start there. Letting 43 psi of fuel spray out isnt a very good idea as it will probably go everywhere. You could probably shoot it halfway across the shop.
If you do get a fuel pressure gauge you should see 43 psi with just the key on (you may have to cycle the key a few times to get it there) system pressure is going to be 33 psi. If you suspect that the fuel pump is on the way out block the return line and start the car the fuel pressure should come up quite a bit, at least double itself. DO THIS ONLY LONG ENOUGH TO READ THE PRESSURE, DOING THIS FOR A PERIOD OF TIME LONGER THAN 5-10 SECS WILL DAMAGE THE FUEL PUMP. That will tell you the max output of your pump, and also show you if the pump got some spunk in it or on it's way out. So yeah borrow a fuel pressure gauge if fuel is what you suspect.


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## djandy (Aug 18, 2005)

Mh... It was ACTUALLY a cylinder that wasn't getting gas because the injector was clogged with gunk again. I guess there was crap left over. Should the filter be on the return or the send? It's on the return but the pump has a little crappy filter on the send. 

Now it works, revvs... at arround 7k it sort of backfires with a little puff of smoke in the back... Still might be crappy sparks or something else?


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