Good Nissan general mechanic
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Good Nissan general mechanic
I was looking for opinions on a good Nissan general mechanic that doesn't freak out because I have some mods done. My last mechanic has retired and I really do not want to use the dealerships. I would prefer someone on the northeast side of st Pete or around hills and memorial. I would rather go to someone recommended here versus picking someone based on a guess.
I've got some issues I can't seem to resolve and don't have the fundage to start throwing money at parts hoping it will fix it.
Thanks in advance for your input!
I've got some issues I can't seem to resolve and don't have the fundage to start throwing money at parts hoping it will fix it.
Thanks in advance for your input!
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There's always Z-Fever.
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You know, somebody actually complimented me on my driving today. They left a little note on the windshield, it said 'Parking Fine.'
You know, somebody actually complimented me on my driving today. They left a little note on the windshield, it said 'Parking Fine.'
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It starts deccelerating while driving. If you try to give it more throttle, you can hear the intake sucking in, but there is no acceleration. It continues deccelerating and the rpms do not raise. It's not like the clutch is slipping, where rpms raise and you gain no forward movement. After a few seconds, it starts speeding up again. Sometimes if I let off the gas for a second or two, it will accelerate again. It doesn't happen every time and it seems sporadic, but more and more frequent Dover the last two weeks. It makes no difference if I am light on the throttle or standing on it.
When the car is cold from sitting overnight or during the work day, it bogs as well. If I turn it on when cold and give it gas, it bogs down, even holding the gas down. Once it runs for a couple of minutes, I can give it gas and rpms will rise.
So far I have changed plugs, cap, wires and rotor and it made no difference. Also cleaned the MAF and filter with no improvement. I also put the stock intake back on to rule out an air leak after the MAF. Again, no improvement. I have not changed crank sensor. At this point I am leaning toward fuel delivery or spark. Maybe the pump or distributor/cam sensor. Cam sensor is integrated in the distributor for my year and is not a servicable part. Exhaust smell seems strong, but not really super rich. It could possibly be an o2 sensor or egr valve also. Too many possibilities for me to just start throwing parts at it.
Hope this answers your question, empire.
KRUKED,
Z fever is not conveniently located for me. I cannot really take the time off to sit and wait for the car to be checked out and repaired. It is not close enough to my job to ask a coworker for a ride from and to z fever.
Thanks again.
When the car is cold from sitting overnight or during the work day, it bogs as well. If I turn it on when cold and give it gas, it bogs down, even holding the gas down. Once it runs for a couple of minutes, I can give it gas and rpms will rise.
So far I have changed plugs, cap, wires and rotor and it made no difference. Also cleaned the MAF and filter with no improvement. I also put the stock intake back on to rule out an air leak after the MAF. Again, no improvement. I have not changed crank sensor. At this point I am leaning toward fuel delivery or spark. Maybe the pump or distributor/cam sensor. Cam sensor is integrated in the distributor for my year and is not a servicable part. Exhaust smell seems strong, but not really super rich. It could possibly be an o2 sensor or egr valve also. Too many possibilities for me to just start throwing parts at it.
Hope this answers your question, empire.
KRUKED,
Z fever is not conveniently located for me. I cannot really take the time off to sit and wait for the car to be checked out and repaired. It is not close enough to my job to ask a coworker for a ride from and to z fever.
Thanks again.
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The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
Last edited by 2000SE; 02-05-2012 at 03:16 AM.
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good job for getting some of the basics out of the way.
seems like people skip all of that and still want someone to diagnose their problems.
What kind of car is it?
bogging down like that can be caused by a few different things.
I would start with the coolant temp sensor. When that sensor goes, the ECU will do all kinds of stupid stuff.
From there, I would want to know what the fuel pressure is. If the fuel pump is stock and has a ton of miles on it, then it is possible that it is taking a crap on you, not getting enough fuel to the rail and the ECU is pulling crazy timing trying to keep itself alive until the fuel can catch up.
It doesn't sound like you are loosing spark because that would be far more rough. And it would be very rare for it to be all cylinders at the same time. If it was the coil, the coil would get hot, the resistance would get too high, and it would drop spark all together until it cooled off. But since you say it eventually catches up with itself, I wouldn't think it is a spark issue.
As for the cam position sensor, those do go bad. But again, that is one of those things that is pretty much good, or not. They do the same thing as the coil. Once they get too hot, they stop working, and the ECU kills the engine and it won't start until it feels like it.
When the EGR is the issue, it is typically at highway speeds. Or cruising with really light load, and it is usually just a vacuum leak when the valve opens. Or it gets stuck open and it can make it tough to start and run like balls because the ECU doesn't know it is open so it just sees a massive vacuum leak.
I would start at the coolant temp sensor. Then Fuel pressure. I would also want to know that the injectors are in good shape. An Ohm test can tell you if they are good or not. I personally would want to pull the fuel rail and actually see the injectors spraying to see how the fuel comes out. Can also help tell you if any of them are leaking or anything like that. I would also check the throttle position sensor to make sure it is reading correctly. (pretty much all of this can be tested with a multi-meter)
somewhere in there, you should uncover your issue.
If not, then I would start thinking about taking it to a shop.
I just wouldn't want to pay a shop 75 buck (or more) an hour to do stuff that I could do myself in an afternoon.
seems like people skip all of that and still want someone to diagnose their problems.
What kind of car is it?
bogging down like that can be caused by a few different things.
I would start with the coolant temp sensor. When that sensor goes, the ECU will do all kinds of stupid stuff.
From there, I would want to know what the fuel pressure is. If the fuel pump is stock and has a ton of miles on it, then it is possible that it is taking a crap on you, not getting enough fuel to the rail and the ECU is pulling crazy timing trying to keep itself alive until the fuel can catch up.
It doesn't sound like you are loosing spark because that would be far more rough. And it would be very rare for it to be all cylinders at the same time. If it was the coil, the coil would get hot, the resistance would get too high, and it would drop spark all together until it cooled off. But since you say it eventually catches up with itself, I wouldn't think it is a spark issue.
As for the cam position sensor, those do go bad. But again, that is one of those things that is pretty much good, or not. They do the same thing as the coil. Once they get too hot, they stop working, and the ECU kills the engine and it won't start until it feels like it.
When the EGR is the issue, it is typically at highway speeds. Or cruising with really light load, and it is usually just a vacuum leak when the valve opens. Or it gets stuck open and it can make it tough to start and run like balls because the ECU doesn't know it is open so it just sees a massive vacuum leak.
I would start at the coolant temp sensor. Then Fuel pressure. I would also want to know that the injectors are in good shape. An Ohm test can tell you if they are good or not. I personally would want to pull the fuel rail and actually see the injectors spraying to see how the fuel comes out. Can also help tell you if any of them are leaking or anything like that. I would also check the throttle position sensor to make sure it is reading correctly. (pretty much all of this can be tested with a multi-meter)
somewhere in there, you should uncover your issue.
If not, then I would start thinking about taking it to a shop.
I just wouldn't want to pay a shop 75 buck (or more) an hour to do stuff that I could do myself in an afternoon.
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That was one hell of a fantastic reply, empire. I appreciate you taking the time to go into such detail.
As for the car, it is a 2000 Sentra SE. It's the roller rocker sr20. It has the original oem fuel system with 160k on the clock.
It really almost does seem like a vacuum leak or fuel delivery/cut issue. I always thought the file pump was a works or not part, but from what you say it could just be wearing out and reaching its end of life. I've wanted to install an electronic fuel pressure gauge for Some time. If that is the case, might as well replace it with a walboro.
Is the egr a serviceable part or just replacement? A few months ago, I noticed the egr tube was hacked off and looked like someone had crimped it with a pair of plyers... And not very well. I used a mechanic who was recommended by a family member and that is the only person, other than myself, who has touched my car. It was probably 2 months (when I changed my oil the next time) that I noticed that butchery. It was doing the decelerate thing even then, but not as bad as now. It has progressively gotten worse. so I ordered a new egr tube, put it on and hoped it would solve the problem. It obviously did not. Maybe from driving it with an essentially open egr system put some crap in it and the valve is having a hard time closing.
Thanks again for the advice. I will check these other things out and see what I find.
As for the car, it is a 2000 Sentra SE. It's the roller rocker sr20. It has the original oem fuel system with 160k on the clock.
It really almost does seem like a vacuum leak or fuel delivery/cut issue. I always thought the file pump was a works or not part, but from what you say it could just be wearing out and reaching its end of life. I've wanted to install an electronic fuel pressure gauge for Some time. If that is the case, might as well replace it with a walboro.
Is the egr a serviceable part or just replacement? A few months ago, I noticed the egr tube was hacked off and looked like someone had crimped it with a pair of plyers... And not very well. I used a mechanic who was recommended by a family member and that is the only person, other than myself, who has touched my car. It was probably 2 months (when I changed my oil the next time) that I noticed that butchery. It was doing the decelerate thing even then, but not as bad as now. It has progressively gotten worse. so I ordered a new egr tube, put it on and hoped it would solve the problem. It obviously did not. Maybe from driving it with an essentially open egr system put some crap in it and the valve is having a hard time closing.
Thanks again for the advice. I will check these other things out and see what I find.
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The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
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if it has been getting worse and worse, then i would really look to the fuel pump being the issue.
just a cheap, inline fuel pressure gauge on the incoming fuel line would be enough to tell you if there is a fuel pressure issue, but with 160k on the clock, I would bet that the fuel pump is on its way out.
the walboro is the cheap replacement option. Just remember, there is a difference between cheap and inexpensive, and the walboro is cheap. Some people have lots of luck. Others end up replacing it almost once a year, and others get bad apples right out of the box. I personally have experienced all 3 at various times with various cars.
Don't forget the fuel filters too. i've seen too many people kill brand new fuel pumps because they forgot to change their clogged up fuel filter.
I would start there and see where i'm at once I know for sure that I am getting ample consistent fuel pressure.
As for the "good or not" that is sort of true. It is true that with fuel injection systems, the pressure has to be right, or it won't work. However, there is still a range it will work in, it is just much more narrow than say that of a carburetor set up. Also, even stock, the fuel pressure is typically a bit higher than it absolutely needs to be. This is done to help with the whole longevity issue. Think of it this way. If the requirement is no less than 40psi. And you loose 2% a year, every year. Then what would be smarter? To start off with 42psi, or 48 psi?
The fuel pump is essentially, just an electric motor. As with all electric motors, as they start to go bad, they draw more voltage. The problem with that is, the wires don't get any larger, so the added voltage heats up the wiring more. As heat goes up, resistance goes up. Eventually, it hits the breaking point where the wire builds up so much resistance that it simply cannot pass any more voltage through. This is when the motor starts to slow down. See, as long as it can continue to pull more voltage, it will do a decent job at maintaining the proper speed. But once the voltage reaches its cap, the motor will slow down. In a fuel pump application, this is when fuel pressure starts to drop. Remember that 42psi vs 48 psi example? Say you are at 48 psi and you need at least 40, well, the pump can slow down, and the pressure can drop down quite a bit before there is a noticeable drop in performance. But once it finally drops to 39 psi, the engine will bog down. Now, applying this to your situation, (and also why it makes sense that it is the fuel pump) when the engine bogs down, the load on the fuel pump drops. It doesn't need to pump as much fuel because the engine is slowing down. This allows the voltage to drop back down. Remember, more voltage = more heat. Therefore, the drop in voltage allows a drop in heat. This allows everything to cool off. Cooling off drops the resistance down, which in turn allows more voltage. The pump can then draw the higher level of voltage again and the engine speeds back up. See how that cycle fits your symptoms?
It is a good fit. Not a guarantee. It could be something totally different and the ECU is just compensating for it by pulling the timing crazy retarded and doing everything it can to keep itself alive until things settle out and then it goes back to normal. but because it is a good fit, it is where I would start.
just a cheap, inline fuel pressure gauge on the incoming fuel line would be enough to tell you if there is a fuel pressure issue, but with 160k on the clock, I would bet that the fuel pump is on its way out.
the walboro is the cheap replacement option. Just remember, there is a difference between cheap and inexpensive, and the walboro is cheap. Some people have lots of luck. Others end up replacing it almost once a year, and others get bad apples right out of the box. I personally have experienced all 3 at various times with various cars.
Don't forget the fuel filters too. i've seen too many people kill brand new fuel pumps because they forgot to change their clogged up fuel filter.
I would start there and see where i'm at once I know for sure that I am getting ample consistent fuel pressure.
As for the "good or not" that is sort of true. It is true that with fuel injection systems, the pressure has to be right, or it won't work. However, there is still a range it will work in, it is just much more narrow than say that of a carburetor set up. Also, even stock, the fuel pressure is typically a bit higher than it absolutely needs to be. This is done to help with the whole longevity issue. Think of it this way. If the requirement is no less than 40psi. And you loose 2% a year, every year. Then what would be smarter? To start off with 42psi, or 48 psi?
The fuel pump is essentially, just an electric motor. As with all electric motors, as they start to go bad, they draw more voltage. The problem with that is, the wires don't get any larger, so the added voltage heats up the wiring more. As heat goes up, resistance goes up. Eventually, it hits the breaking point where the wire builds up so much resistance that it simply cannot pass any more voltage through. This is when the motor starts to slow down. See, as long as it can continue to pull more voltage, it will do a decent job at maintaining the proper speed. But once the voltage reaches its cap, the motor will slow down. In a fuel pump application, this is when fuel pressure starts to drop. Remember that 42psi vs 48 psi example? Say you are at 48 psi and you need at least 40, well, the pump can slow down, and the pressure can drop down quite a bit before there is a noticeable drop in performance. But once it finally drops to 39 psi, the engine will bog down. Now, applying this to your situation, (and also why it makes sense that it is the fuel pump) when the engine bogs down, the load on the fuel pump drops. It doesn't need to pump as much fuel because the engine is slowing down. This allows the voltage to drop back down. Remember, more voltage = more heat. Therefore, the drop in voltage allows a drop in heat. This allows everything to cool off. Cooling off drops the resistance down, which in turn allows more voltage. The pump can then draw the higher level of voltage again and the engine speeds back up. See how that cycle fits your symptoms?
It is a good fit. Not a guarantee. It could be something totally different and the ECU is just compensating for it by pulling the timing crazy retarded and doing everything it can to keep itself alive until things settle out and then it goes back to normal. but because it is a good fit, it is where I would start.
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Again, thank you for the logical reply. That makes a lot of practical sense.
I remember about two years in to ownership, I started looking for the fuel filter for my car. It turns out there isn't one, in the traditional sense. Apparently it only has a sock type at the pump. Always thought it odd. I traced the fuel line all the way to the fuel rail and sure enough... No filter. I may take a look at a 98 or 99 and see if I can integrate theirs, just as a precautionary measure. If not a sentra, maybe an Altima or 240.
That was a revelation on the walboro. I thought that is what all the turbo guys went with. Because it was reliable. I agree with you regarding cheap vs inexpensive. I may just get one from a local dealership or courtesy in TX. If the oem one lasted me 12 years, it would be safe to assume I would get at least 6 from another unit. I'm pretty sure I have an extra egr around here, so I will swap that out as well for good measure, after testing the fuel pressure.
I will report back after the weekend and let you know what the test results are. Thanks for all of your advice so far!
I remember about two years in to ownership, I started looking for the fuel filter for my car. It turns out there isn't one, in the traditional sense. Apparently it only has a sock type at the pump. Always thought it odd. I traced the fuel line all the way to the fuel rail and sure enough... No filter. I may take a look at a 98 or 99 and see if I can integrate theirs, just as a precautionary measure. If not a sentra, maybe an Altima or 240.
That was a revelation on the walboro. I thought that is what all the turbo guys went with. Because it was reliable. I agree with you regarding cheap vs inexpensive. I may just get one from a local dealership or courtesy in TX. If the oem one lasted me 12 years, it would be safe to assume I would get at least 6 from another unit. I'm pretty sure I have an extra egr around here, so I will swap that out as well for good measure, after testing the fuel pressure.
I will report back after the weekend and let you know what the test results are. Thanks for all of your advice so far!
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The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
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That was a revelation on the walboro. I thought that is what all the turbo guys went with. Because it was reliable. I agree with you regarding cheap vs inexpensive. I may just get one from a local dealership or courtesy in TX. If the oem one lasted me 12 years, it would be safe to assume I would get at least 6 from another unit. I'm pretty sure I have an extra egr around here, so I will swap that out as well for good measure, after testing the fuel pressure.
the better pumps, like the 300zx pump aren't more popular because they can cost $300 bucks. Whereas a walboro costs under 100 bucks.
good idea to test the fuel pressure first.
good luck
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Follow up
I have unfortunately been working for 28 days straight with no day off until today. (before i strarted this thread even!) The joys of being an overworked/underpaid employee. Luckily the car is still running, albeit badly, and getting me to and from. Today is my first day off and I have quite a bit of catching up to do.
I am shooting for tomorrow to at least test the fuel pressure and TPS voltage and will report back the results. I'll check the FSM and see what the recommended procedure is.
Thanks again for the solid advice. I will keep the thread updated so others with the same issue might find solace and resolution.
I have unfortunately been working for 28 days straight with no day off until today. (before i strarted this thread even!) The joys of being an overworked/underpaid employee. Luckily the car is still running, albeit badly, and getting me to and from. Today is my first day off and I have quite a bit of catching up to do.
I am shooting for tomorrow to at least test the fuel pressure and TPS voltage and will report back the results. I'll check the FSM and see what the recommended procedure is.
Thanks again for the solid advice. I will keep the thread updated so others with the same issue might find solace and resolution.
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The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
The glass is neither 1/2 full or empty. It simply contains 50%of its total capacity.
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