Pretty common for aftermarket struts to have a higher pressure gas charge. I've run into this problem replacing just the fronts. It raises the front higher than the rear.
The plastic intake is shrinking in the cold and it develops a vacuum leak. It manifests as a clatter on cold start. The damper plate is rattling because the ICE is not starting right away. At first they were replacing just the gasket, now it's the gasket and manifold. Only happens when you get below about 25 deg F for a low.
When you say "2nd gen", are you referring to the 2004-2009 model year Prius; or the 2010-current model year Prius? Since you are talking about a "plastic intake", I assume that you are not referring to the 1.5L Prius (2001-2009) engine which has an aluminum intake manifold. The only plastic intake part that I recall is the air cleaner housing...
Thanks, I believe that you are referring to the issue documented here? NEW!!! Service Bulletin for Engine Knocking at Startup T-SB 0012-10 | PriusChat
So for those who are replacing struts are they only replacing the strut mounts and bearings also? My 2002 Prius with 143,000 rolls like a boat and clunks on bumps and pretty much rides terrible. My thoughts without actually getting under and checking all the components were that the struts are toast. Are there other suspension components that people are also replacing like control arm bushings or ball joints? I would get under and look but it has been extremely cold. TomK
I would replace the struts and the strut mounts as well as the rubber "spring insulators" that sit above and below the coil springs. The insulator above the coil spring also serves as the pleated rubber cover.
+ on that. I have replaced fronts with KYB, together with top mounts at 110k miles. I have replaced rears with OEM - had no problems ordering them. Car drives like new now. No bouncing. - Alex
Are the strut mounts a dealer-only item, or are they available aftermarket like the kyb struts. SM-N900V ?
For Gen 2 you can probably find them at non-dealer . I use Rockauto.com for many years. I'm not associated with them, just customer. But, personally, for item like a mount I would go with one of the online Dealer part stores. - Alex
I also would buy the correct Toyota parts, when it comes to the strut mount and the rubber spring insulators. If you want to buy aftermarket KYB instead of the Toyota-branded KYB struts and shocks, that's up to you.
I could see that in Seattle. Here in Denver/Wyoming, where we see on many days as much as a 60degree Farhenheit temp swings, are roads are utter garbage. I could see getting 130k+ out near you in Seattle....but here that is a TALL order when many guys I know with 18" tires and 45 series profile wheels have to pray not to replace them from a sidewall puncture due to our potholes
Lots of mixed answers in here, I have a prius gen 2 with 171k on it. I took it into firestone yesterday and they wanted $1500 to replace the back and front struts and shocks. He showed me cupping on the back wheel but I do over inflate my tires and never get the car aligned. The rubber spring insulator was pretty destroyed on the front shock also. What do you think? I don't see having this car more than 2 more years. Is it worth it?