Help buying a new ECU

So after a long and trying time with getting my 2001 Nissan Sentra fixed, all I need to do now is replace the computer. I’m wanting to save money by getting it online.

Thing is, I looked it up on Google, and one result I found recommended going as far as to get the car’s VIN and call Nissan to get the exact ID number of the ECU that I should get. I went to and found that there are many different kinds of ECUs for the same make, model, and even year of a car.

I do have my old ECU’s serial numbers, which are actually totally different from it’s ID number. Can I get just any 2001 Nissan Sentra ECU, do I have to go as far as to call Nissan with my VIN, or is the truth somewhere in between? Thanks.

Yes, the VIN contains code numbers which need to be decoded by the car’s manufacturer. The firmware in the ECU is often updated during a model year as problems arise or adjustments are necessary or changes in other components are introduced. There’s a lot of information in that little 17 place alpha-numeric code.

Might I recommend that you just have your Nissan dealer replace the ECU? From what I am led to believe, a new ECU has to be activated by a PC or test set on cars with OBD systems. Here again, the dealer has the codes that must be put in. Plus, when connecting the ECU into the cars electrical system, you may stand a chance of causing a voltage spike and there goes the new ECU.

I’m not trying to make money for your dealer, just trying to save you possible grief and heartache.

Good luck.

Well, the whole problem with the old ECU was that I originally gave the car to the dealer to fix something else and they did a terrible hack job that, among other things, fried the ECU because they wired it backwards. This has taken weeks to undo. So I really wouldn’t trust them to get within a 400-foot radius of my car ever again. Note that I live in American Samoa, where different levels of competence are to be expected.

My other option is to buy a $300 ECU from a local independent mechanic who says that he has the right one. I believe he also has the computer equipment necessary to put the codes in. Should I just get it from him? It would cost a bit more. If I buy it from him, would it be necessary to double-check with Nissan?

Do you live on Tutuila? (the main island in the group, a 5 by 10 mile flyspeck in the South Pacific)…Why do you need a car?

Yes, I live on Tutuila, but I think you’ve been given some bad info about the size of the island. As you can see, it’s really more about 20 miles wide. Most of the roads run right next to the shore of the oddly-shaped island with lots of curves. It takes about 30 minutes just to get to work in the center of the harbor from my home halfway to the western tip of the island. Nearly every family here has a car.

Anyway, back to getting my new ECU…

If the dealer caused all these problems why aren’t they fixing them FREE! Regardless of how you feel about this particular dealer I would go up the Nissan corporate chain until this got fixed at no cost to me. They could keep the car for as long as it took.

My other option is to buy a $300 ECU from a local independent mechanic who says that he has the right one. I believe he also has the computer equipment necessary to put the codes in. Should I just get it from him? It would cost a bit more.

Sounds like a bargain to me if you think the guy can do the job. You probably don’t know, but are the Nissan’s sold in Samoa configured the same as those sold in the states? If they are Australian or East Asian versions allowed in the territory under some quirk of the law, and if your local Nissan dealer is as questionably competent as you fear, the fact that the VIN identifies the configuration may not be as much help as you might wish.

If I buy it from him, would it be necessary to double-check with Nissan?*

Hmm. what exactly do you expect Nissan to say?


BTW, are you sure the old ECU is dead? Was it the same dealer that you don’t trust who pronounced it dead? ECUs are pretty sturdy. Has the local guy verified its demise?

My instinct is that it’s probably a US-style Nissan, since this is a US territory. Since it didn’t come with a manual, all I can really say with 100% certainty in regards to what country it was made for is that it can’t be for Australia because it’s made for driving on the righthand side of the road.

What I mean about checking with Nissan is asking if I should call corporate-level Nissan with my VIN and ask them for the exact ID # of the ECU that I should be looking for.

I’m pretty sure the ECU is dead (well, not dead, but with enough important circuits damaged that it needs to be replaced). Both independent guys have verified that. They were recently able to determine that the dealer rewired it in such a way that it forced 12 volts into a circuit that was meant to carry 1/2 a volt in the opposite direction, overwhelming a diode.

Because of this post and some advice that I’ve gotten IRL, I think I’m going to buy the one that the local guy is selling. Thanks.

If it’s a US-spec car, it’ll have a sticker under the hood that says something to the effect of “complies with all federal and state emissions regulations for model year 2001” on it.

Thanks. I talked to the mechanic working on it, and he found the sticker saying that it complies with California emissions standards, so it’s a US-style car for sure.

Here’s a small concern: I used an online automatic VIN decoder (leaving out the car’s serial number, of course) and it said that it had an invalid check digit, a sign that it may have been copied down wrong by the mechanic or myself. But then we double-checked, and it was correct, so I don’t know what that means. Should I be concerned at all/will this effect my ability to get the new ECU, since I likely need the VIN to get the exact correct ECU?

Anyhow, it turns out that there was a misunderstanding and that the second independent mechanic will actually be ordering it, so it will be at least a week before I have a working car again.

Get a cheap golf cart. I could ride a bicycle from one end of that island to the other and back in a day. Why have a car at all?

But, it seems you would likely find that the dealer would be the best source and getting the Nissan factory Representative involved is my recommendation, also.

I guess even paradise has its problems.

I was hoping to avoid telling the whole story, but here goes:

Back in March I was having some moderate problems with my car. I took it to the dealer, got it back a few days later and they were still there. I took it back, insisting that I shouldn’t have to pay again for the work they had previously not done. They decided that they would fix it for no additional charge other than the cost of parts. A few more days later I got it back in a horrifying state. The whole thing shook horribly when idiling and the “Check Engine” light went from being on to flashing. The whole thing seemed ready to explode. They wanted $125 for a single new starter coil, which I later learned could be purchased on eBay for $25. Thus far I’ve managed to get out of paying that. I showed it to two new mechanics and it the wiring job made them both take a step back with shock. Among other things, the wiring changes had fried my ECU.

A few weeks later, while the car was still being fixed by the new guy, I got a bill from the dealer for $260, even though they knew by this time that I was not exactly satisfied with the work they had done. I don’t know where they got most of those new costs, but only about $2 of it was interest. I called them up and explained why I wasn’t going to be paying it. They said they’d wave the bill for me. Somehow I doubt that’s happened.

To really complicate things, the dealer is a major sponsor of the tiny radio/TV station that I work for, so I need to keep halfway-decent relations with them. Going over their heads and complaining about them to Nissan would probably mess that up.

So, in short, I’m not doing that because I don’t want them to ever get within a 200-foot radius of my car ever again, but I have to keep at least semi-decent relations with them. Plus if I went there they’d probably (wrongly) tell me that I owed them money that would have to be paid before they could do any work. I feel like asking for any more free things from them, even things that they owe me, would be pressing my luck.

EDIT: I forgot one of the more obvious reasons: Since I’ve had someone else working on it, the dealer will probably claim that the damage to the ECU was the other guy’s doing. Although I know for sure that it was their fault, I’m unable to prove anything. They already attempted to pull the same stunt when I told them I wasn’t about to pay them for their “work” that damaged my car.

Like I said before, the island may be small as the crow flies, but the random shape of the island, its mountainous terrain and its extremely curvy roads make it hard to get around. If the roads were stretched out straight, you would have a much easier time understanding how far my commute actually is. What you see on the map above is almost all of the roads on the island, and the roads are much curvier than they appear. It takes about 30 minutes to drive from my apartment near the Star Mound site to my workplace in Pago Pago. I once walked from the same workplace to Utulei and it took three hours. If you look at the map closely, you’ll see that Pago Pago to Fagatogo is a mile in and of itself.

I don’t think anyone here sells golf carts anyhow. Plus they couldn’t hold up to the poorly-maintained roads.

See above for why I’m avoiding the dealer, but I’m now beginning to consider them as a last resort again b/c of the advice here.