Our new to us (September 2011) 2003 S has thrown a P1688 code twice. We are the second owner and the car has about 26K miles currently. Both events occurred under hard acceleration at approximately 4.5K RPMs. The car goes into limp mode but resets after a key cycle and seems to be fine afterward. The car does not seem to develop much power until higher speeds/RPM's are achieved and is rather sluggish, especially off idle. Would the consensus of opinion be to replace the Bypass Valve? Also, any positives on the Detroit Tuned modified valve? ScanGauge2 freeze frame data: PID02 = 1688 PID03 = 0400 / Loop is Open PID04 = 3F / LOD = 24 PID05 = 85 / WT °f = 198 PID06 = 80 PID07 = 89 PID0B = 6C / MAP PSI = 15.8 PID0C = 22FA / RPM = 4477 PID0D = 73 / MPH = 71
The last time I had that code my damper pulley separated. That being said Cycling the key did not fix my problem. I was able to limp it home and noticed as soon as the SC started making boost it would go into limp mode. I also had smoke coming up from the pulley side as it was cooking my serpentine belt.
Welcome to M/A, thanks for joining. P1688- Electronic throttle control monitor level 2/3 mass air flow calculation Most likely with a car of that vintage the crank pulley is going south. That would be the first place I would look. The pulley has a rubber center for a vibration damper. Over time with heat and use the rubber starts to split, the center around the crank will continue to spin, the outer portion wit the belt wrapped around it will stop. Get this checked very soon as it can lead to overheating once it separates. The Supercharge will stop spinning and that drives the water pump. There are a few aftermarket alternatives out there. My thoughts are to go with something that has a damper, OEM or not.
Thanks for the welcome! I will absolutely check the crank pulley/damper, good advice. Guess I'm still confused on this though? Our car is a 2003 but only has 26K miles. Sure, the rubber in the damper could deteriorate from ozone but likely not from use with such low miles? We have no "rubber burning smell" and A/C on, or off, makes no difference. This is why I was leaning toward the BPV. But this is new to me. When the crank pulley/damper fails, wouldn't it be a catastrophic event and not an intermittent one that rears its head at 4.5K RPM's under hard acceleration? Trying to learn.
The pulley is something to look at. unfortunately it can look perfect on the car and be falling apart on the backside where you can't see it. When mine failed the only rubber burning smell was from the belt itself. Are you able to consistently get the code? you could try reaching your hand under the intake tube and feel how hard it is to move your bpv. But without a gauge of knowing what your feeling for it might not be of any use. another option if you are able to remove the belt you can feel if there is any play with the pulley itself. Mine was so bad I could turn the belt surface by hand (that should not be possible)
I was able to duplicate the above errors this afternoon on the freeway. Same scenario, same captured data. The plan at this point from some expert advice received: - Zip Tie BPV and test for recurrence/resolution of event - Replace crank pulley/damper with ATI Super Damper, as preventive maintenance in light of vehicle year '03, and test for recurrence/resolution of event We also intend to add a tensioner stop, new belt, and (as long as we're in there) a 15% SC pulley. Comments?
Reach around the back of the IC output duct and place a finger on the BPV arm which extends from the BPV diaphragm to the butterfly pivot, press inward and release, the arm should move with slight resistance and return; feel and listen for a metallic tink noise, which is indicative of a broken spring. Also observe the arm while the car is started, it should move rearward instantly, and return when the engine is turned off. If the spring is resilient, time to remove tension from the belt, grasp the crankshaft pulley and attempt to rock it, if it strikes the timing chain cover when pressed upward with palm, replace.
+1 on what k-huevo advised. Just recently replaced a done OEM damper on an 05 R53 w/ just 21k miles on it. If it's the damper, go ATI.
I replaced my stock crank pulley with the ATI unit a few months ago. I posted a write-up with pics here: http://www.motoringalliance.com/library/1st-generation-mini-cooper-how-to-3/replacing-the-crank-pulley-101/
Thanks for the link to the write-up, I appreciate it! I did some ordering of parts today and have a question for you... Did you have any issue with the "39" belt? I plan to run the Alta v2.0 15% pulley and the ATI 1% (0.08?) damper and that's the belt I bought.
I've been running the '39 belt with my stock crank pulley and 16% supercharger pulley for about 4 years with no problems. I got the stock sized ATI unit and have no issues with the belt for the past month or so, including one track weekend.
We plan to run the Denso IK22 (#5310) Iridium plugs with the 15% SC pulley reduction. We'll also be running the MSD coil and 8.5mm wires. What are the spark plug gap recommendations with the colder plugs and hotter ignition with this setup?
Don't waste your money on the MSD. The OEM does a better job. The MSD is a Dodge Neon fitment and requires some footwork with the bolts. Not at all worth the effort unless you want red. As to wires...OEM are also one of the best options, many of the aftermarket sets have proven to be junk. About the only ones worth it are the Kingsborne and again, unless you want them color there is not reason to use anything but the OEM wires. That's my opinion and I've tried many of the them out there, both coils and wires.
Yeah, well, too late on the waste of money issue... :lol: The attractive point to me, as to the MSD coil, was the brass terminals vs. the steel terminals of the OEM coil. Upon inspection, our '03 has the terminal #3 rust issue and the #3 OEM wire end was rusted too. Any advice on the spark plug gap for the colder plugs?
.040, guess it's too late to steer you clear of the Denso plugs also. I recommend checking plug torque after a few heat cycles, again after a couple thousand miles (can't be done too frequently thereafter), remove and inspect the sparkplug center electrode before ten thousand miles.
Went from the Densos to the NGK Iridium plugs, they work great, can be found at your local Advance Auto and are a bit cheaper. :thumbup:
Other than price, any experienced difference in performance? The Denso's I bought (IK22/5310) were $9.74 each (incl. ship and tax) I can get NGK's (BKR7EIX/2667) for $7.85 each (incl. ship and tax) The Denso is a 0.4mm fine wire with u-groove and the NGK is 0.6mm. I plan to monitor the Denso wear every 5K miles or so and replace them at 30K as recommended.
I had that code twice while on the hwy for a few hours on-cruise. It went limp, and cleared after a key cycle and never came back. Even if your OEM crank pulley/damper is 'good' it likely on it's way out anyway given the vintage. You may consider replacing it anyway as insurance, I recommend as Nathan suggested OEM or aftermarket with a damper. I have the ATI. Many cars make big HP on stock plug wires and coil, if you like the looks of the aftermarket great, but it will not make or free any hp/tq unless what you have is in poor condition. And Welcome to MA.