All right long story short, old motor had rod knock so I bought a new one from Soko. Installed it got her running but turned her off to finish some stuff up. Next day I tried to start it and wouldn’t start. Steve (nismo91) came over to help and we came the conclusion that it was weak spark. (As it turns over and starts to catch but not fully to start, also vacuum was blocked. It started with the vacuum hoses blocked and open.) So I bought a distributor and installed it. The first time I tried it after the distributor was in, it wouldn't start. So I tried again the next day and bam she started. Ran and idled for about 20 minutes and I turned her off after I moved into the garage. The next day I hooked up some more things. (Brakes, transmission) Started it (right up), drove it out of the garage and parked because I still had to put on the hood and I forgot to put a hanger on the exhaust. Put those things back on went to start the car and crank crank crank :mad: Will not turn over. So I just figured that I would try to unplug them and start it (it did before). But nothing, only cranking again. Please help! This is driving me crazy. :confused:

EDIT: The car is a 1998 Sentra Se. It went from lowport to lowport. Used the intake manifold and everything else off the US motor.

Hmmm....
Check the grounds, battery to block, one on the intake mani, one on the tranny.
Since both motors were lowports why did you have to use your old intake manifold?

Have you pulled the injectors to see how they look?

Have you checked the TPS and MAF voltages with the ignition on?

When you got it running, how was the idle? high, bouncing, perfect? Did you get a change to adjust the timing and idle?

Ok. Grounds were redone and all attached.

I had to use the intake mani because the motor was JDM and it does not have the emission stuff.

The injectors were off the other car and working fine. Looked good when installed.

I have not tested the TPS and MAF. Where should i test those at? At the connector or what?

When i had it running the last time it would sit at 1500 and than bounce a little 1200-1800 than go back to 1500. I did not get a chance to do the timing either. It is set by eye.

maybe swap in a known good coil prior to all that other stuff.

quick. easy.

It's unusual, but coils do go bad.

I just bought another coil. I checked and i have spark

i know when i put in my jdm (highport) i forgot to plug up a harness underneith the battery tray and had similar problems. check all you harnesses. i

Yea when Steve was over we checked it all. Its the weird thing that it HAS started but seems to decide when it wants to start again. So like mostly everything is hooked up because it ran fine. But than just decides to shut off and not run again.

well start with the basic's, what is your fp? you have spark, so you know that, did you use new plugs with the motor? is your tank full? what are the plugs gapped to? how close are you on your timing? did it run good when it did run or did you just let it idle? what temps outside are we dealing with? check tps & maf voltage & all vacuum lines. is the tps bolted on well?, maybe it was loose and moved out of calibration. , ecu plugged in nice & tight also, you sure the dist is tight also and isn't jumpin around. just a few things to think about to start.

OK..
Just curious, can you up plug the injectors without having to unbolt anything else? I did not know that there were JDM motors built as lowports, I am curious if I am wrong or if you actually have a highport.

I previously asked you to check the injectors but actually I was thinking about the spark plugs. If you pulled the injectors out of the rail, now the seals may be leaking so you would be running really rich. do you smell a lot of gas when you were cranking it? If your spark plugs are all black on the ends there is a good chance that you are running rich. this could be because or leaky injector seals or maybe you plugged in the injectors 1-2-3-4 instead of 4-3-2-1.

Do you have a repair manual for the car? It spells out how to check the Maf and TPS.

The idle seems too high but it should still be starting for you this is probably not the main problem.

Well i swapped over the intake mani. Its a lowport, i cannot get to the injectors. I did not get new seals though on the injectors. I never took them out of the rail though. They did come out of the intake manifold. When i pulled the plugs the contacts had gas on them. I belaive that cylinder 4 is leaking because when i crack it with no spark plugs in gas SHOOTS out of the cylinder. The spark plug ends are not black. I just bought new ones to make sure they were good. It goes to start. Like it cranks starts to carch and goes to 300 rpm and than just dies back to cranking. Also on the intake tube after the maf and before the throttle body there is a whole in the bottom. Where does the house attach to that is supossed to go into that hole? I can take pictures tomarrow. I also found 1 loose connector and i do not know where it goes.

yeah that will cause your problem, a huge vacuum leak after the maf will let unmetered air in and cause big problems, gas will shoot out of the cyllinder if you pull the plug out and keep the fuse for the fp hooked up, where else is it going to go? if you take the plug out it will come out the plug hole. have someone take a look at it near you, see if they can help you out.

The hole in the intake track is for the idle hose. You probably did not connect the idle hose so your car wont read the that should be going through the maf when you are trying to start it. That sounds like you found the problem, just connect the hose on there. I am not sure if that made any sense...

Have you seen how secure your battery terminals are on the posts?

Sounds basic, but it happens *all* the time, and can cause starts-up-now-and-then symptoms.

Well I have the problem of i cannot find the hose :confused: Where does it attach to besides the intake? Also one more question. On the intake manifold in the back and below there are 3 vacuum attachments and than 3 below that. I have an Haynes manual but it does not have the vacuum hook up for those. That’s why they are blocked off right now. Can anyone tell me where they go.

Thanks for all the help so far guys. I Really appreciate it.

I think the haynes manual has the picture for routing the vaccum lines. It will be too confusing to try to expalin. If you see the picture it is much easier. The idle hose comes out of the manifold about 3 inches away from the throtle body at about 5-o'clock if you are looking at it from the driver side fender (highport). It should be similar on a lowport.
Hope that helps, if you can't find it let me know I will check on my car or I can take a pic.

http://www.sr20forum.com/img/data/500/11102starting.mpg Short video inside the car of the tach. (yes i know i need a starter) If you could take a picture that would be very helpful.