[borrellimd]

So I have a bad intake valve as discovered by comression testing (you can hear and feel the air coming through the intake with the valves shut when I put compressed air into #2 cylinder.) Can I repair and or replace the 1 head or do I have to do both heads at the same time? I was looking at getting a rebuilt head for 300$ but I don't know if 1 rebuilt head and 1 original will cause any problems.With 220K miles on the engine, for under 400$ I could get another 150K miles or more from the rest of the engine but I don't know if 1 new head will cause a problem. Also, it is odd to me that the same cylinder on 2 different 01 Siennas have developed a bad intake valve. Is there a known issue that would cause this? Any other owners have a bad #2 cylinder intake valve?

 

[happycamper]

I would try some sort of SeaFoam top engine cleaner first. Any chance the valve is sticking in the guide?

 

[borrellimd]

Took thehead off and could see valve not seating fully, could pour water through it. Icould not tell if it was bumped/damaged. I am to understand that these are noninterference engines but I have heard that that is generally true at low rpm,high speed and if any bit of carbon will cause damage. Furthermore, I have nowseen this on 2 engines. This original engine described above; highway speed waypast time for new belt and it skipped some teeth (not sure how many) ran crappyat higher rpm and threw a handful of codes. Drove it another 10 miles or sobefore eventually replacing the engine. Second engine with a bad valve was in a2001 XLE I bought for parts with a bad engine. 1000$ was good for parts and ithad nice leather seats and other parts I could have used. Just c1ouldn't scrapit because it was so nice. Bought a rebuilt engine for 1500$ add another 1000$for every axle, bearing, and bushing, ect and we are driving essentially a newvan. The original engine had a bad valve. They were different valves, can’texplain what happened to them, both around 200Kmiles...