2007 ZR6 - Throttle Position Sensor issue??????

[layneherring]

Searched hard but can't find anything like I am having. 2007 SV211 with ZR6. Fresh non eth fuel. New fuel filter. Advance to full throttle and engine will go to 3000 rpm but not further (throttle is fully advanced). Will stay at 3000 rpm for approx 15 - 45 seconds then finally it is like you flipped a switch and bam it puts you back in your seat like a bat and goes to 5000 rpm. Throttle off to 3500 rpm and still feel lttle surging every once in a while. Perfect pass turned off at all times, but it almost feels like when PP takes over feels when you use that. Most times when coming out of whole I can't get full rpm until the 30 or 40 second wait time. Seems to become less of an issue the longer boat runs, but still noticeable. After turning off engine then back on seems to be worse for a while. Could it be something in the fly by wire system? Any thoughts appreciated. Thank you.

one more maybe not related thought. Perfect pass not performing as well as last year when engaged and seems to be really varying at holding constant speed (i.e. set at 18 mph may let it down to 16 then up to 21mph)

[wakeskier]

Does you check engine light come on at all?
I have a 2007 220 w/ZR6 and the check engine light was coming on intermittently, I had the codes read and it was the TPS.
There's 2 voltage readings and both of mine were just out of spec, the shop adjusted them back in and the light hasn't come back.
I never experienced any performance issues though, even with the light on.
Good luck with your boat

[layneherring]

Never have had a check engine light. Performance issue/RPM issue only. Just so strange to have a max rpm of 3,000 at full throttle, then it will be like you flip a switch and it will increase RPM to 4,800 and take off. Makes it quite interesting getting up on a slalom.
Thanks for the reply.

[layneherring]

Thought I would post end results. Fuel filter replacement did not yield immediate resolution of problem. Continued to occur randomly. Got down to where I could put 20 gallons of fresh fuel (when de winterinzing was only able to add 4 gallons of fresh fuel). Problem seemed to slowly go away and performance is not great. In my opinion I did not add enought Stabil to the fuel for winter storage (which was longer this time due to water levels, Sept - June). Will in the future store with minimal fuel (non ethanol of course) and plenty of Stabil, adding fresh fuel when de winterizing. Thanks for the reply.

[hotrod508]

My 07 SAN 236 did the same thing.... The TPS sensor gets wet from water dripping off the motor hatch, this changes the can bus signal to the motor, makes a irratic signal. You can dry it out with a hair dryer... You also need to dry the plug connector. In the end, i replaced it and smeared silicone along the outside of the TPS case. Anything that changes the flow of the signal can change the way the computer reads the signal so I avoided dielectric grease.

Sent from my SAMSUNG-SGH-I337 using Tapatalk 2

[Bbruyer123]

This is a pretty old thread but we have a 2007 236 and it is doing the exact same thing that you describe. Which I think is interfering with the perfect pass performance because it seems to have difficulty locking on to set speed. Either dips ways down or surges passed. Did you ever figure out what the solution was to this problem?

[srock]

This may all sound counterintuitive or nuts. I have gone through this twice, and there are a number of threads on ZR6 spark plugs causing and curing similar issues. Many running problems, particularly under load, appear to be a fuel delivery issue, a failed injector, or weird perfect pass performance, but it's actually the spark plugs. Sometimes, running the boat may clear the issue temporarily and bring performance back to normal, only to have it act up again on the next warm-up.

Here is what I have learned...change the spark plugs. The ZR6 is extremely sensitive to the proper spark plug and, in some cases, the age of the plug wires. Running the ZR6 frequently will lengthen the plug's life span, while sitting or storage appears to shorten its life. You need to install the stupid expensive iridium plug and not an "equal". Amazon will offer up cost-effective equivalents, but Nautique Parts will get you the proper plugs. You will find conflicting gap information, but new plugs need to be gapped correctly at .060, but note that they will typically come packaged at .045. When adjusting the gap with a gauge, avoid damaging the thin point at the tip of the electrode by forcing the gap tool in.

My long-time and outstanding mechanic noted his belief that when the ZR6 is shut down, fuel sitting in a cylinder, usually impacting two cylinders, over time will affect iridium plugs, where they will not fire or they may misfire on those specific cylinders. Heating or running the boat where is clears out the gremlins may temporarily help. The last time he illustrated the issue by swapping plugs and showing me that the problem followed the plug.

Engine performance issues easily lead you down the wrong diagnostic path. Give the plug swap a try, and please report your findings back to the group.

[Bbruyer123]

I had not seen your post about the spark plugs. But we did replace them as a first step (since that is easiest and a good place to start) and the boat is still doing the same thing. It seems to only happen when we have the ballast full and are surfing with the boat. Everything will be fine, no other issues what so ever, and then we go to throttle with the perfect pass set and you can push the throttle all the way down and it still won’t go past 3000 rpm. We have no idea where to go from here

[jpwhit]

Have you checked fuel pressure? Check it at idle and under load when you're having the problem.

[Bbruyer123]

Come to find out my significant other changed the spark plugs with ones that you can get at Napa. Is that not equivalent to the iridium plug that they have at Nautique parts- and would that really make a significant difference?

We have not checked the fuel pressure but we will do that next!

[jpwhit]

The plugs sold at Nautique parts are exactly the same as what you can buy at Napa. All the matters is the part # is the same as what came out.