Need Help! SR Won't Start, Starts, Won't Start, etc.

Simontibb · 08-08-2010, 10:10 PM

I have this in the SE-R section as well but no real replies, it's a 91 SE-R Sentra..SR20DE.

The car has been broken for almost three months now it seems, my girlfriend drove it home from work and it was fine, we got in it to get dinner, it wouldn't start.

So I immediately started trouble shooting the obvious. It gets fuel and spark. I changed the plugs, rotor, cap and some other things. Still no luck, then fried the starter trying.

I recently put on a new starter, MAF, and TPS. It started after charging the battery, ran fine for the few minutes it ran, then I turned it off to clean up and tighten a few things, tried to start again, FAIL. I looked at the ECU and found a ground coming out entirely undone, fixed that up and went home for the night.

Today I charged the battery again, it started, turned it off, still no luck starting it back up a little while later.

Went and bought a new battery as the old one was declared dead.

Still won't start.

What else can I check? IT HAS to run ASAP. I am so lost on what to check! I know it has spark, it's getting fuel, the pressure is unknown but it's flowing, I've cleaned a lot of sensors, NO CEL, no codes, WTF?!!!

nismo chris · 08-08-2010, 10:40 PM

try changein out the ecu and see what happens and make sure the little nut that holds the ecu clip in is all the way tight ive had that come loose and cause this problem

UI8281 · 08-09-2010, 02:00 AM

Have you tested the voltage off the alternator. Just a thought.

Simontibb · 08-09-2010, 08:20 AM

I'll see if I can find an ECU and I'll check the clip. Thanks.

I haven't checked the voltage off the alternator. Am I just checking for consistency?

Simontibb · 08-09-2010, 01:30 PM

So this morning the first thing I did was unplug the coolant temp sensor and the little plug next to it I think for the gauge. I then took the plugs out and cleaned them. I then unplugged the fuel pump fuse. Turned the engine over to blow any fuel out in case it was flooded. Put it back together. It started right up, I thought sweet, the sensor is bad causing it to dump fuel and foul the plugs...wrong. It went back to not starting a few minutes later. WTF?!?! Is there anyway to check the ECU?

Nitelife · 08-09-2010, 01:45 PM

http://www.se-r.net/engine/ecu_codes.html

Simontibb · 08-09-2010, 02:06 PM

Oh darn thanks that may help!

Simontibb · 08-10-2010, 12:59 PM

Checked codes.

I have a consistent code for the CAS...where is this located? In the distributor? Is it replaceable or do I need to get a while distributor?

Does the coolant temp sensor have anything to do with CAS? Can they interfere with each other AT ALL?

Simontibb · 08-10-2010, 04:01 PM

By the way it starts every morning but if you shut it off and let it sit it won't start back up until the next day.

UI8281 · 08-10-2010, 11:51 PM

The CAS is in the distributor I believe. Not sure if it is replaceable on it's own. And I don't think the coolant sensor will interfere with the CAS at all. If you had a faulty coolant temp sensor your fans should be running non stop and the ECU would show that code.

Simontibb · 08-11-2010, 09:11 AM

Quote:

Originally Posted by UI8281

The CAS is in the distributor I believe. Not sure if it is replaceable on it's own. And I don't think the coolant sensor will interfere with the CAS at all. If you had a faulty coolant temp sensor your fans should be running non stop and the ECU would show that code.

Good point there, I unplugged it as I read if it was bad it could prevent the car from starting and when unplugged both fans ran and I got that code, so I will rule that out and focus on messing with the CAS.

Simontibb · 08-11-2010, 09:53 PM

Update, I am still thinking CAS as I am getting the code.

When I first try to start it everyday it starts, but will eventually stall out after a few minutes. While running it runs fine, it has a slight hesitation/miss under load revving but no crazy sounds.

After it died, trying to restart it it sounds like it skips. What would cause it to start then not start back up until hours almost a day later? Could it be the CAS? Or is something else throwing that code? Is there a ground to check around there?

UI8281 · 08-12-2010, 01:50 AM

If the ECU is flashing the CAS code then the CAS isn't working as it should. I just thought about it now that my sisters subaru used to do this exact thing and was really temperamental about starting, to start it the CAS had to be wiggled as it was separate to the distributor, this problem was solved with a replacement sensor. So I say go and get a replacement distributor and see how that goes. As for starting then not starting it could be heat or vibration or even possibly oil seeping in through from the cam. And as for the stalling and missing I'm guessing your CAS will most likely be the culprit as well since it controls the injector timing (I think).