Engine wont start

[Mr. Spool]

after my 91 engine swap into a 96 I am not able to get the engine to fire up. I am getting spark and there is fuel in the rail. I am not sure if the injectors are firing. I have not messed with the timing but I did switch the distributors so I figure I will have to at some point. any help would be greatly apreciated. Thanks.

[Eternal_240Sx]

battery? Starter?

[JustinHallenbeck]

pull you plugs. Crank it over and see if you smell fuel. If you do you know your injectors are working. And i dont mean just a hint of fuel, you should smell it very strong. Also check to make sure your distributor is in right, maybe its 180 degrees out. Make sure piston number one is on TDC on the compression stroke, then put your distributor in at the correct location. It should be almost at/around cyclinder 1.

[Mr. Spool]

I just checked the compression and it came out between 120 and 135 per cylinder. I know this is extreemely low but I would think that it would still fire up. could this cause it or is it something else.

I found out my injectors are working. what would the alternator and battery have to do with this. also if you could please explain the distributor thing I would apreciate it.

Any other sudjestions would be apreciated. Thanks.

[JustinHallenbeck]

I don’t think its a bat or alt problem. You have enough power to fire sparks... The Distributor things...

Take all you sparkplugs out. Take a wrench to you crank pulley and crank it over, with your finger over the spark plug hole (gotta almost seal it) crank it over and see if you fell pressure building up. It their is your on your compression stroke. If you don’t you on your exhaust stoke, turn it 360 degrees and then it will be compression. You can also pull you valve cover off and watch the valves to see when all of them are close on cylinder number one but this is a lot harder.

Now, for the next part you wanna crank it over slowly to bring the piston all the way up to the TDC position.

TDC meaning the connecting rod journal is at the top dead center of its rotation. Think of it like this, you have a circle that the journal follows, " O " now run a vertical like threw the center of that circle and where the top of the circle and the vertical like intersect is where TDC is.

One way to get the piston to TDC is the put a long screw drive in to the spark plug hole and SLOWLY crank it over. The screw driver will start to rise. Watch it and when the piston starts the reach the top it will start to rise slow. Then at the very top it will stop.. at this point you wanna crank it over about 1/64 a turn (a very very little). You can also check your timing marks and it should be lined up. Your piston number one is now at TDC.

Now you wanna take your distributor and open the cap and make sure the rotor is point at the electrode for cylinder number one. Do this by making a mark on the base of the distributor with the cap on. Follow the spark plug that cylinder number one down the side and make a mark. With the cap off point the rotor at the make and slow slide it in to the hole. Making sure that when it meshes with the drive gear that it still points to the mark you made. But the cap back on. And hook your coil and spark plug wires up.

Try cranking it over, it may start.. if it trys to start and stumbles it maybe be one tooth off. Pull the distributor up just a bit and turn it in one direction one tooth and try starting it again... if it gets worse pull it out again and go two teeth in the other direction.

Hope this helps if you have any question just ask.

[Mr. Spool]

I hope I got all of this, I will try it tommorow night. Could any of this affect my compression numbers of is my engine pretty much shot. and you are saying that even with my compression like this I should still be able to get the engine to start.

[idlafie]

You might want to double check your ground wires. Check the grounding point on the engine block above the 02 sensor. Make sure it's grounded to the firewall area to the left of your brake booster. If your engine is not properly grounded, your ECU may not be getting the signals from the engine sensors necessary to start your car. I found this out the hard way 6 months ago when there was a short in my ground connector and my car didn't want to start...no fuel & no spark..but yet the ECU said everything was perfectly fine...No Diagnostic Trouble Codes!!. It took a certified Nissan mechanic a day to figure it out what the problem was.
Anyhow, hope this helps..
ID

[Mr. Spool]

Thanks for the imput, I believe that I am getting spark and fuel. I even tried starting fluid. but still nothing happened. Tonight I will try putting my distributor to top dead center. Any more thoughts or ideas would be greatly apreciated.

[Mr. Spool]

so let me get this streight the valves have to be flush with the walls. and I need to pull the distributor rotor off and then replace it where it needs to be. any other info.

[Mr. Spool]

Thanks for the heads up, I finally got it to start and idle, I retested the compression and know I am getting 170, 170, 170 and 155 what can I surmise from this, does this mean that the car will run rough or should I be okay. Thanks for the imput

[JustinHallenbeck]

Umm did you do a wet and dry compression test? Also what was the problem, how did you get it to start. Also with your compression numbers they look about right, i dont know what spec is but looks ok to me.

[Mr. Spool]

spec is around 180, I just got the car running by getting it to tdc then let it run for several minutes. After that I decided to do check the compression again. I am slightly worried about the difference in the first three cylinders and the last one.

[andrave]

I bet your compression was low before because you had hella fuel in your cylinders, it can leak between the rings and the cyl walls and lower your compression reading.

[JustinHallenbeck]

Other way around andrave... fuel in the cylinders would create higher compression. It would create higher compression numbers for two reasons. One the luquid acts as a seal/lube and makes the piston rings seal better, less blow-by. Also you cant compress a luquid, so if you have fuel taking up some of the volume of the combustion chamber when its a TDC the air is forced into a smaller space. Making a even higher compression.

[JustinHallenbeck]

You should do a dry and wet compression test. Unplug you injectors, and coil and put the throttle to WOT then crank it over. Check your readings for all 4 cylinders. Then do this all over again but spray a little "Brake away" or some type of lub fluid like WD-40 in the spark plug holes. Then compair the numbers. Your wet compression numbers should be a little higher. If the wet compression numbers are with in 10 (pushing it) it should be ok.