03 M45 Y34 US spec TB problem please help!

Had a question maybe someone can help me out.

     I've owned my 2003 Infiniti M45 for almost two years now. It has about 87k miles and I do regular 3000 mile full synthetic Mobil 1 oil changes.

     Early last summer I had an issue where if I would sit in 90 plus degree weather with the AC on, the car would overheat (while moving no overheating was occurring). Also a raspy ticking was coming from the water pump area. I checked the thermostat, radiator cap(for proper pressure) and it worked fine. 

     Later that summer, I made a 1500 mile trip in the M and the problem got worse. I took it to a local mechanic and he said that it was the water pump. I then took it to another mechanic who said that it was something else entirely. We then came to the conclusion that it was the hydrolic fan reservoir that had no fluid in it. So i filled it with Lucas synthetic power steering fluid (it fills very slowly), and the noise went away and the over heating was less apparent. Then I cleaned the space between the radiator and the condenser and no overheating has occurred since then. 

     Not to long after this, on a usual morning when I went to start the car, it started fine but when I went to press the accelerator, the car wouldn't go past 2-3 mph. I turned the car off then on again and it was fine after that. Later a couple of weeks after that, it started to happen more often till one day I had to turn the car off and on again over 20 times to get it to go back to normal. I took it to a mechanic that was recommended to me and he said that possibly my throttle body was going bad or dirty. So I cleaned it with throttle body cleaner. While cleaning, I moved the throttle flap open and close a few times to clean inside and around in there. It worked fine after that for a good while(although the idle was about 200 rpms higher than normal after the cleaning).

I noticed the check engine light went on and off for a month or so till finally it just stayed on till today.

     This past fall, I took it to another mechanic who said that he knew how to fix this throttle body problem. He informed me that the TB was bad so i ordered a new OEM TB from infinitipartsonline.com ($440+). 

     I had him drop it in. He had some sort of a hand held pc that looked like a fat 13 inch LCD tv. he was able to shut off the injectors individually and view rpm's, temp, and other info while the car was running with this pc hooked up to the OBD port. The device he used had a slot to insert different chip style keys to it. He finished the job and said pay me and take the car and drive it and let me know how she feels. 

     This was around February of this year and up until recently(two or three weeks ago) I had no problems (except for the check engine light being on). Now, the car starts fine, but the idle is around 1250 to 1300 rpm's all the time and I only have about 30-40% power. Even at full throttle, it takes about 12 to 14 seconds to reach highway speeds. Shifting is erratic, and fuel mileage is horrible(6-7 mpg city). Also, above the 4500+ rpm range, the engine seems to not want to climb anymore. Almost like all the power is coming in at about 2500-3500 rpms. At times if i turn the ignition on and off a few times it will work fine. But 85% of the time its erratic. The VCS/SLIP and service engine soon lights are lit up. 

     I know for a fact that the mechanic didn't reflash or reprogram the ECU. He did reset the idle control but I don't think he did anything other than that. 

     How can I go about repairing this with as little money as possible? I'm not cheap, but I am unemployed due to lay off and my money is very limited. 

     Your help is priceless and i would owe you tons if you could help with any advice. 

     Thanks in advance.

     -Jesse

I would suggest with all you've gone through, either bite the bullet and take it to an Infiniti dealer, or find a mechanic who specializes in Nissan and Infiniti cars only.

On a side note, I'll never understand the "3000 mile oil change with synthetic". Part of the whole deal with synthetic oil is they hold up 10 times longer than conventional oil, and there is no benefit to changing it at 3k other than for your conscience because Jiffy Lube has told you to change it every 3k for the past 30 years.  Besides, Mobil 1 is not a true synthetic oil, it's a blend. Amsoil, Royal Purple, those are true synthetics, and you can drive a  year on them, not 3000 miles. I've been changing my oil on mine and my wifes cars once a year with Amsoil for over a decade and never had anything but smooth running cars.

Anyhow, good luck, I hope you get it fixed right next time.

My understanding is that synthetic doesn't necessarily last longer but rather doesn't break down under high load and temperature. I noticed that my Q45 runs quite hot and takes a long time to cool down. My F350 Powerstroke diesel has  extended oil changes of upto 7500 miles, but because the injectors are electro-hydraulic and extremely sensitive to oil contamination, I do oil changes at every 3000 miles, especially since I had to change the injectors a few months back. Parts and labour to replace the injectors is $3500, so 16 liters of oil and filter is cheap insurance.

[QUOTE=jesustorres85;337096]Had a question maybe someone can help me out.
 
I've owned my 2003 Infiniti M45 for almost two years now. It has about 87k miles and I do regular 3000 mile full synthetic Mobil 1 oil changes.
 
Early last summer I had an issue where if I would sit in 90 plus degree weather with the AC on, the car would overheat (while moving no overheating was occurring). Also a raspy ticking was coming from the water pump area. I checked the thermostat, radiator cap(for proper pressure) and it worked fine. 
 
Later that summer, I made a 1500 mile trip in the M and the problem got worse. I took it to a local mechanic and he said that it was the water pump. I then took it to another mechanic who said that it was something else entirely. We then came to the conclusion that it was the hydrolic fan reservoir that had no fluid in it. So i filled it with Lucas synthetic power steering fluid (it fills very slowly), and the noise went away and the over heating was less apparent. Then I cleaned the space between the radiator and the condenser and no overheating has occurred since then. 
 
Not to long after this, on a usual morning when I went to start the car, it started fine but when I went to press the accelerator, the car wouldn't go past 2-3 mph. I turned the car off then on again and it was fine after that. Later a couple of weeks after that, it started to happen more often till one day I had to turn the car off and on again over 20 times to get it to go back to normal. I took it to a mechanic that was recommended to me and he said that possibly my throttle body was going bad or dirty. So I cleaned it with throttle body cleaner. While cleaning, I moved the throttle flap open and close a few times to clean inside and around in there. It worked fine after that for a good while(although the idle was about 200 rpms higher than normal after the cleaning).
 
I noticed the check engine light went on and off for a month or so till finally it just stayed on till today.
 
This past fall, I took it to another mechanic who said that he knew how to fix this throttle body problem. He informed me that the TB was bad so i ordered a new OEM TB from infinitipartsonline.com ($440+). 
 
I had him drop it in. He had some sort of a hand held pc that looked like a fat 13 inch LCD tv. he was able to shut off the injectors individually and view rpm's, temp, and other info while the car was running with this pc hooked up to the OBD port. The device he used had a slot to insert different chip style keys to it. He finished the job and said pay me and take the car and drive it and let me know how she feels. 
 
This was around February of this year and up until recently(two or three weeks ago) I had no problems (except for the check engine light being on). Now, the car starts fine, but the idle is around 1250 to 1300 rpm's all the time and I only have about 30-40% power. Even at full throttle, it takes about 12 to 14 seconds to reach highway speeds. Shifting is erratic, and fuel mileage is horrible(6-7 mpg city). Also, above the 4500+ rpm range, the engine seems to not want to climb anymore. Almost like all the power is coming in at about 2500-3500 rpms. At times if i turn the ignition on and off a few times it will work fine. But 85% of the time its erratic. The VCS/SLIP and service engine soon lights are lit up. 
 
I know for a fact that the mechanic didn't reflash or reprogram the ECU. He did reset the idle control but I don't think he did anything other than that. 
 
How can I go about repairing this with as little money as possible? I'm not cheap, but I am unemployed due to lay off and my money is very limited. 
 
Your help is priceless and i would owe you tons if you could help with any advice. 
 
Thanks in advance.
 
-Jesse[/QUOTE] do you have an after market alarm system ... i will explain why once you have answered that Q ..
 
BTW MODS please move to the Nissan section i am sure we can get more input there ..