Hi all,

Been reading for a while here and have really enjoyed learning from you guys/gals. Currently having some serious issues and hope things can be rectified before its too late. Appreciate any help in advance.

My car: 2003 350z Touring 113k miles. Purchased at 102k. Only mod known is Injen CAI single. However, cone filter does not run to the bottom of the car and sits in the engine bay.

About a month ago I brought the car into the mechanic (new mechanic, the usual guy was too busy to get a hold of and the new mechanic came highly recommended by a friend) to get a few issues looked at. These included the following: some mild grinding when going 1st - 2nd which actually had resolved itself over time, but wanted to see if it was one of any other indications related to a looming clutch/synchro problem; feeling of engine power loss (after I dropped it off, I read on here that it may be related to the knock sensor pending code in which case it would be worth replacing the sensor and sub-harness); and alignment issues (recently involved in a passenger-side impact accident. $3.5k later you couldn't even tell. Covered by the at-fault driver's insurance, obviously. Also, it did spend some time on the frame machine, if that's relevant). Mechanic ended up doing brakes, alignment, and told me o2 sensor (S2B2 i believe, but don't recall exactly) needed to be done in the near future. Also, he noted there was a hole drilled into something (again, I'm not sure, but I'm 99% sure he said intake tube) by the last guy to have the car, and that it was letting unfiltered air into the engine so it needed to be plugged. OK, cool. Go for it.

As soon as I get the car back, it begins to stall when the clutch is depressed, typically coming off of high RPMs (losing power steering @ 40 mph on the exit ramp definitely keeps you on your toes). It happens fairly consistently over the next few days, and finally decide to bring it back over to have it looked at. I'm thinking, based on a few posts I read here, perhaps the hole was drilled intentionally, in which case "please undo what you did". Also important at this point in time, I did my first oil change on the car. I had previously brought it religiously to JiffyLube to have synthetic done every 4k, and wanted to learn how to do it myself with the girlfriend's dad; bonding and whatnot. As I watched only 2.5 quarts drip out, I realized how badly I had screwed up by going by the sticker and never checking the dipstick on a regular basis. We put in 5 quarts of M1 synthetic, new bosch filter, and drove it over to the mechanic for round two.

Second stay at the mechanic resulted in the following:

- Error codes P0011, P0021 present
- Found the hose that's supposed to go into something on the intake on the bottom of the engine bay. Reattached it.
- Added: Crankshaft position sensor, Camshaft position sensor (x2), Cam Actuator Solenoid (x2) and oil pressure switch. Removed: entire savings account

Also, oil had to be changed 3 times throughout drive tests because so much engine gunk was coming out. Also, mechanic remarked on aluminum found in the oil on the removed cam actuator solenoid. ****. Mechanic used regular oil/detergent mixture to clean, and I left with a fresh mixture when I picked the car up. He said the plan is to come back in 3k miles to switch back over to synthetic.

Since getting the car back, the problem is EXACTLY the same. The RPMs dip dangerously low when the clutch is depressed, sometimes falling so low the oil pressure light comes on and the engine stalls out and dies completely. Also, there are some new and terrible sounds chiming in at around 3.5k RPM and I'm afraid to drive it. Mechanic says to drive it for a while and come back if it persists.

In the meantime, I've done the ECU reset, accelerator pedal reset, throttle body closed position reset, and idle reset procedures. No dice.

Thanks in advance for anyone who (1) read through this novel and (2) has any advice. Super desperate here.

 

Just updating with solution in case anyone experiences anything similar in the future.

Issue turned out to be chain tensioner. During the brake repair (don't ask me how) the tensioner plastic began to crack apart and thus began the appearance of the other symptoms.

 

So was it the timing chain tensioner or the belt tensioner?

 

He hasn't logged in for 10 years