18th Aug 2007, 14:22

My Sentra Spec V runs like a champ when it wants to, or it sometimes doesn't want to go over 10mph and the engine will only rev to 1500rpm. It is very random; this problem comes and goes. It could run great for 1 day or 1 week or even 1 month, but I never know when my car decides to go really slow on the freeway

I want my 79 Caprice back. I can't believe I traded in my restored classic for this car with a mind of its own. Yes it is hard to start too.

I have a new engine, 2 new cats, and all the problems still.

25th Oct 2007, 22:39

Wow I can't believe all the negativity toward Nissan here. The problems I have locally are not necessarily with Nissan it is the Ford/Nissan dealer. I over heard an employee say I don't give a sXXt about Nissan and this is customer service! At least fake it people. I do admit my earlier days with Nissan before the merger where much smoother. It is best if you can find a dealership that is Nissan only. There are also private shops that are certified to do warranty work; these guys are less likely to side with Nissan or any other large corporation, and will be a lot more firm with the factory.

As for Sentra problems, I have a few fixes if any one is interested. Here we go:

There are a few crank angle sensor problems out there; mine was one. Have the factory do this; it is under warranty.

There is also a piece of foam around the ECU that can attract moisture in high humid climates and short out the ECU. Have only a Nissan tech do this; a Ford tech did mine and killed my ECU and wiring harness. Ooops! You have to disconnect the battery first!

The early fuel pumps do not have a check valve in them, so if you park your car up hill it won't start in the morning. I am in the process of purchasing a 05 fuel pump out of a wrecked car. A cheaper method would be a manual inline check valve. In the mean time park on either a flat surface or nose pointed down hill with ebrake on so as not to jam the tranny. Remember to move the key to the acc position for approximately 3 seconds before turning over the car; you will hear a high pitched whine, which is the fuel pump priming the system. If you do not do this the car will not start reliably. If you get to the point where it won't start at all, hold the pedal to the floor like a carb muscle car. I know it is throttle by wire, but it has got me out of a jam in the past. Be prepared for the revs to come up quickly and the car to run very rich for 5 minutes.

A good electronic stabilization system is good to purchase as well from a company like Apexi; this makes sure there is no excessive static buildup in your car and will eliminate a lot of "ghost" issues.

If you live in a hot environment you will notice that your car will not want to restart even though you have been driving it for hours; this is from electronic saturation. Again the voltage stabilizer will relieve this static buildup from the vehicle and will start much better.

Best mod ever is to remove what is called the pre cat convertor. It robs mileage and when the hot exhaust gases hit the cat it returns into the exhaust port, causing the dreaded oil consumption problem. This mod produces great HP numbers; remember to relocate the O2 sensor behind the primary cat so as to pass emissions and not throw the check engine light.

Some engine hesitation has been attributed to early knock sensors as well; use an 05 version. The purpose of a knock sensor to to "listen" to the pinging of detonation and retard the timing so as to not harm the engine. The knock sensor specked out is over aggressive and is the reason why your spec some days feels on crack, and some days feels sick.

If your car won't drive over 10mph it is in either safe mode or the mass airflow meter is dead, meaning the computer is confused why you have the accelerator pushed to the floor when there is "no" air flowing into the engine. Be sure to lock tight the butterfly screws on the intake otherwise they will fall into the head and #1 failure.

Last thing I can think of is the head and block, although both aluminum, are controlled at 2 different temps which will cause the head gasket to eventually fail (can anyone say LT-1) There is a T junction that regulates how much flow goes to the block and how much cools the head; simply eliminate the flap to have equal flow. This could make your car run a little cold in the winter.

Now that you know a few tricks, don't get discouraged. These are modifications that I have done on other vehicles as well. If you are like me, I was expecting a car finished from the factory, but you don't always get that. That is why these boards are here. Remember, out engineer the engineer, and you will live a happy life. Best of luck all.

P.S. - 2.5 coming out VQ35de swap going in.

20th Jan 2010, 23:22

I bought one of the very 1st SER 2.5 on 12/19/2001. Needless to say, it had a few problems.

First oil consumption was the first motor, and the second one that I had to pay out of my own pocket due to expired guarantee 3 years later.

Before that, the ECU had to be replaced; it was done free by Nissan.

The last motor I put on it was from a 03 Nissan Altima 2.5. Ever since, the car's runs like a champ. I put 2nd stage cams, headers with no cat, and a cold air intake. It dynos at 208hp at the wheel.

21st Apr 2010, 13:08

Guy from Jan 20, 2010 2322. Does your car pass inspection after eliminating the precat by adding a stock exhaust, and does your new header have O2 sensors on it?