I am sort of leaning towards a bad coil or possibly a vacuum leak on my 97 SE 5 speed. It stumbles/misses/hesitates... I'm not sure how to correctly diagnose it, but those words come to mind. It's not horrible, and it's not backfiring or misfiring, but something just isn't right. The problem is intermittent and more noticable at different engine speeds. It is also really not noticable if you're on an open road and the car is just cruising. But, shift gears, lug the car out of a corner in a higher gear, or put it on the floor going up a steep mountain and it hesitates like there is no tomorrow. I'm afraid to take it to the Nissan dealership or a mechanic because I don't want to spend alot of $$on it. I just put almost $600 in it for a fuel pump, a CEL reset, an evaporator something or other, filters, and plugs. I really could use some advice.

Thanks in advance!

 

sounds like a faulty coil pack. They run about $70 each!! Finding tha bad coil pack is the hard part

Ant

 

This sounds like it could be a coil/injector. Slowly unplug each coil pack one at a time. when you pull off or unplug the harnass from one of coil packs you will notice the engine rpms drop and the engine will idle shakey. When you hit a bad coil pack you will notice that the rpms will not change. This is a good test to see if it is coil pack/ injector... be sure to test both injector or coil pack at that point to see which is faulty. I did this test on my 95 and found a bad injector to be the problem. I had similar symptoms also so be sure to check out both..

be sure to plug harness back into coil pack before going to next coil..

 

You can pull the coil pack and measure the resistance between two of the terminals to determine if it's faulty.

 

Yes the resistance level should be at a certain level for both the coil and the injector. You will need a volt meter for this to measure.

 

Can you elaborate on measuring the resistance. I've never done it, but I'm pretty handy and do have a multimeter. I just don't know exactly what you mean. What do I set it on and when level should I look for. Also, do I do the same for the injector? I appreciate the help.

 

Sure.. you need to switch you volt meter to ohms... Then put each needle on the contact points within the coil so that you can determine the resistance value. If you give me a sec I will try to find the correct resistance vaules...

 

lance if you send me your email I will send you some pics and values for this...

 

I just had my 1995 in for what sounds like the exact same symptoms. Turned out to be the injector on the #6 cylinder. After that everything was running smoothly. Cost was $205 part/labor.

 

i have about 8 spare coil packs left....i know one of them doesnt work so let me know if you want me to send you a few to try out.

 

Injectors and Coils are pretty easy to do... I did my #1 and #6 it cost me a little over $200 to do both of them. I did them within 1.5 hours. You just need to be sure to get the intake gasket and o rings for injectors..

 

You really do not need to know the correct resistance. Test them all and the one that is different is the bad one.

 

It could also be your knock sensor. I know when I had gotten some bad gas my car was doing everything you are saying...once I got it up to speed, everything was fine but if I wanted to accelerate or do anything it would hesitate and slowly go...wasn't fun. Anyway if it is just the knock sensor sometimes it doesn't trip the CEL. So, you can pull the code to find out. Just look in the FAQ on how to do that. If the code comes up for a knock sensor then you know it is a bad knock sensor. Just another you can check.

-John

 

My car has been throwing knock sensor codes for the last few months. I dropped by the dealership yesterday and it had the code again, but no CEL. I've been told in the past that it is a ghost code and doesn't mean anything. Is that true? Would a bad knock sensor cause these symptoms and if so, how much will it cost to have taken care of? Thanks for all the help on this post. I'm ready to run this car into a tree!

 

Go buy a vacuum guage. I suggest MityVac ($30) because you can bleed you brakes with it too. Disconnect the vacuum line to the fuel pressure regulator and check the vacuum. Vacuum should be STEADY with 21-17 Hg. If you open the throttle quickly, the vacuum should drop quickly and then bouce back up when you let off the throttle. Spend another $17 on a Chilton's service manual and they'll tell you how to check nearly all the electrical components on your car with a multimeter. You can even check the knock sensor. There are WAY too many people blaming the knock sensor for their problems even though they have no codes and they're too lazy to by a $10 multimeter to check the $120+ sensor. I guess some guys have more money than sense.


Dave

 

Your car will spit a knock sensor code if you have to much engine knock from a faulty injector. My 95 spit out that code and once i replaced my injector it no longer gives me code. I am sure that your knock sensor is fine. I am willing to bet you have a bad injector.