2001 Cranks But Doesn't Start, Possible ECM Problem

[Andrew1234]

Today while I was driving my 2001 Nissan Sentra GXE I lost power, all the dashboard lights came on, and power steering and brakes were gone. After coasting to safety, I found that the engine cranked but wouldn't start.

I had it towed to a nearby service station to be fixed. After a few hours they called me saying it "seems" to be the computer and it will cost $1000+ to put in a new one. Also, they said that after installing the new ECU the car would need to be towed to a Nissan dealership to be reprogrammed (seems strange - I don't have a security or key immobilization system). I said I would tell them what to do tomorrow. Anyway the issues they have found are:
-No communication with scan tool
-Injector pulse but no spark

I have seem some others with similar problems, particularly this thread, where it turned out to be corroded or broken wiring. I'm planning to tell them to check for this before doing anything else. However, since the dashboard lights (check engine, oil, and e-brake for sure) came on when the problem occurred, I'm worried that this may not be it (doesn't that mean the ECU is alive?). I haven't checked whether they still come on when the ignition is turned on.

Anyway, I have seen that there are many knowledgeable people on this forum so I was hoping for some good advice. Thanks.

[mike_s]

My 03 SE-R has been notorious for hard starts and the occasional no start from time to time. I purchased it used in 06 with 18,000 miles on it. Within the first 6 months I had starting issues and I finally had to have it towed in for service. It's been a few years now, but I believe they said it was the "throttle chamber" that needed to be replaced and they also replaced the ECU at that time. I was fortunate that it was covered under warranty. One of the techs here may correct me, but I think the ECU was replaced for the foam issue.

That sovled the bulk of my problems for a while, but last year I encountered starting issues again and the car behaving erractically. This time I tracked it down to the infamous cam and crank shaft sensors. Replaced both myself and was on my way. Next up was the car having hard starts and going into limp mode with no warning. After a little more research and a changing the plugs I tracked it down to bad ignition coil. Swapped that out and everything went back to normal.

Do you have a CEL on and have you checked any codes? If it is the cam or crank sensors, they should throw a code for you. When my ignition coil went bad, I got a misfire code for the cylinder that was having problems. I'm far from a mechanic, but I've found that digging around on this forum and a little elbow grease has saved me a lot of $. I don't think you can completely rule out the ECU, but their solution to fix it there, then tow it to Nissan sounds suspicious. If it has to be towed in to a dealership, why not have them do all the work. They should know the car better than anyone else. Just my $.02 and past history with a Sentra that doesn't always fire on the 1st crank. (funny/strange note, my car has always started better when using my remote start, than when putting the key in the ignition. no idea why that is.)

[Andrew1234]

As far as I know this is not a problem with hard starts - it won't start, period.

As I said, they hooked up their code scanner to the car but got no response from the computer.

I did have the foam-related recall work done a few years back.

I called the Nissan dealer and they said they would have to do their own diagnosis, but if it turned out to need a new ECU it would probably cost about $2000-$2500, which is outrageous.

[mike_s]

$2000 - $2500 for a computer on a 10 year old car is ridiculous. I wish could be of more help. Best of luck getting it sorted out, maybe someone more knowledgable than myself in these matters will reply. Where are you located, maybe there is tech on here that you can at least bring it to their dealership/shop locally? They go out of their way to spend time helping people like us on this forum and I would seek one of them out if possible.

[Andrew1234]

Update: The mechanics in the shop were well aware of the wiring issues but have ruled them out and are confident that the ECU itself needs replacement. I'm looking to get a used part shipped in to keep the cost under control.

[tooch420]

hey guys, got one for you too...I got a 03 GXE and it seems to start when it feels like it. Most of the time it starts fine, but once in a while it will crank and no start. If i wait a sec and try again it turns over. Sometimes, it cranks and cranks and no go, like it did before x-mas, but i went to try it couple days later and it started up fine and has been ever since. The only code i am getting which no one can figure out was a cooling temp code, which supposedly was the thermostat..changed it and code wont go away. I dont think its related, but cant get rid of it...and no other codes present.

[Andrew1234]

Final update in case anyone else is reading this thread. My car was in a couple of different shops for nearly 3 months before they got it running again. I ended up having to take it to the dealership.

The problem was... wait for it... the wiring. However, even the dealership didn't discover this until they installed a brand new ECU and tried to start it up, at which point a small fire started under the hood. They were then able to trace the root cause to a short in the wiring harness, which had fried the original ECU and also took out a crank shaft sensor. So they had to order a new wiring harness from Japan, which took forever.

Anyway it's working now and I'm not quite bankrupt, so it's time to move on.

[mike_s]

Thanks for the update. Never fun tracking down issues in wiring. These little Sentras can be a PITA sometimes.

[JudoJohn]

They didn't try to make you pay for their mistake, did they? I would fight that, THEY missed the wiring short the first time. That should be on them, not you!