two problems after rebuild, knock sensor and overheating at cruise

[ubernoob]

Hi all, hoping you folks can give me some pointers for some problems I'm getting on my '04 RXP.

I had my engine rebuilt at the end of last season due to exhaust valve failure (Jet Shed in UK rebuilt engine, I fitted it). On the first ride (and every ride since) I've had the knock sensor out of range error code (P0326)). Also today I kept getting an overheat alarm when cruising around 5,000 RPM (below this I didn't get the alarm). When the alarm cut in the engine seemed to misfire but this could be the ECU protecting the engine from running at full power when the alarm is sounding. After the alarm stopped the ski ran normally again. Also the ski seems to be labouring on full power, and it hasn't got the pull that it had before - plus the exhaust note sounds like the supercharger is really under load when on power.

The ski has got an Riva blow-off valve fitted, but I'm not sure if this is faulty. Reason for this is when you apply throttle you get quite a bit of air coming out of the blow off valve, I thought it was only supposed to do this when the throttle was closed and there was quite a bit of boost between the s/c and the air intake valve.

I'm going to pull the jet pump tomorrow and check I haven't picked up any weed. But if it's not this any tips on the overheat problem?

Also, any tips for the knock sensor problem. I'm losing my patience with it! I've taken it off twice now and it's still not fixed - is there a way of checking the knock sensor itself? I've read the pigtails can also be a problem, I think I have the extra bit of harness, but is there any way of checking the wiring? Also, I'm assuming the overheat problem couldn't be caused by the knock sensor problem - is this a fair assumption?

Thanks in advance for responses. I'm getting so frustrated that I've invested hours (and $$$) rebuilding the ski and I'm still getting problems right at the start of the season!!!

A.

[suck my wake]

["The ski has got an Riva blow-off valve fitted, but I'm not sure if this is faulty. Reason for this is when you apply throttle you get quite a bit of air coming out of the blow off valve, I thought it was only supposed to do this when the throttle was closed and there was quite a bit of boost between the s/c and the air intake valve."]

The blow off valve should only be open when cruising and off throttle, closed when in boost. Maybe its stuck or the hose not connected properly

As far as the over heat alarm, make sure all your hoses have no blockage. Sounds like your not getting enough water into the exhaust, that could also account for the different sound you are hearing. Maybe try running it on the hose and see what happens and where the water comes out.

Have you checked to make sure the knock sensor is tight against the block, not just the bolt being tight but the sensor to the block? I know its hard to get to but if its loose it will definately cause you alot of issues.

Check those out and let us know.....

[ubernoob]

Thanks SMW, I did check the ski on the hose and I was getting water out of the exhaust and the jet pump, so there is flow on the hose. But have have got my me thinking.... I did have a problem routing the intercooler hoses when reconnecting them, I wonder if I've crimped one and this is limiting the cold water flow to the intercooler and then onto the exhaust manifold, I guess this could cause my problem? Also, I didn't realise the exhaust gas temperature sensor also could trigger a high temperature alarm.

As for the knock sensor I'll take the intake out today and check as per the workshop manual. Will also check the jet pump for obstruction.

[suck my wake]

Thanks SMW, I did check the ski on the hose and I was getting water out of the exhaust and the jet pump, so there is flow on the hose. But have have got my me thinking.... I did have a problem routing the intercooler hoses when reconnecting them, I wonder if I've crimped one and this is limiting the cold water flow to the intercooler and then onto the exhaust manifold, I guess this could cause my problem? Also, I didn't realise the exhaust gas temperature sensor also could trigger a high temperature alarm.

As for the knock sensor I'll take the intake out today and check as per the workshop manual. Will also check the jet pump for obstruction.

Yes make sure the hoses are not kinked, that would be bad The temp sensor in the waterbox in not for EGT its just a temp sensor and that is most likely what is setting off the alarm, not uncommon if your running too hot. Just make sure your hoses are good and routed correctly and that none of them have any blockage like something crawled in there while the motor was out and died As long as they are clear you will have good water flow and that sensor won't go off.

[ubernoob]

Here's the update... took the intake manifold off today and removed the knock sensor, checked the resistance in the service book of the knock sensor (about 5M ohms), all good, check the resistance on the add on wiring harness, all good. So cleaned the surfaces of the knock sensor, added Loctite and re-torqued.

Now ref. the overhearing, I checked the routing of the hoses for the intercooler, couldn't see anything particularly wrong, also pulled the jet pump to make sure there was nothing blocking, and there wasn't. But I did notice the small hose that goes back to the water bottle from the cylinder was a little kinked, so I drilled a small hole in the seat frame and cable tied the hose up, so it doesn't kink.

As for the test ride, well it's not overheating anymore (and it didn't sound laboured under load like it did before, plus the power is back to being strong - perhaps I had the intercooler hoses on the wrong way round???) but I'm still getting the bloody P0326 error code when I hit around 6,000 RPM (with the message check engine). I am going to try draining down the gas tomorrow and replacing with some fresh 95 octane. If that doesn't fix the code I'm completely out of ideas, other than buying a new knock sensor!

If anyone else has any other suggestions I'd be glad to hear them! If not I'll update this thread when I've tried new fuel, hopefully tomorrow.

[ubernoob]

I drained most of the old fuel today and filled up with fresh stuff, but the bloody P0326 error code is still coming up.... So I have now: removed and cleaned up the knock sensor, re-torqued to correct amount, checked the ohm reading on the sensor, checked the ohm readings on the pig tails and changed the gas. I have one last idea, when I re-fitted the engine we had lost the original knock sensor bolt so we replaced it with one as per the Seadoo parts catalogue (M8 x 35mm), but I see we've added a washer on top whereas the schematic doesn't show a washer. Could this be causing the problem? I can't see how it can but I stand to be corrected, any opinions out there, or any other suggestions?

[beerdart]

Try it without the add on pigtail.

[ubernoob]

Try it without the add on pigtail.

Cheers 'beerdart' I've just done that and whilst I can't really simulate riding outside my house I ran it for a few mins taking it up to 6k to 7k RPM and I didn't get the error code whereas I was before - so maybe the pig tail is the problem. I'll take it out on the water Saturday and give it a good run. Do the pigtails fail? I did run the check as per the manual and check the resistances and they were within limits.

If the code doesn't appear should I just replace the pigtail with a new one or leave it off?

[beerdart]

If you get no code leave it off.

[ubernoob]

If you get no code leave it off.

Any impact of not running the pigtail (don't really want to put the skit at risk in any way)?