Master Scotty,
I have a 2006 Toyota Sienna with 180k miles (automatic 3.3L V6 VVT-i)
I'm having trouble diagnosing an intermittent no-start issue that started immediately after filling up at the gas pump. (Just to be clear - no turn, battery good)
Scanned for codes right away and found P0442 - "Evaporative Emission System Leak Detect (small)". Did a little research and went to auto parts store for evap valves and hoses (checked gas cap seal first)... when I returned several hours later to my van (still at gas station), it started right up without replacing or repairing anything.
I drove it home and proceeded to replace 2 black plastic valves - "vapor canister purge valve/solenoid" (under the hood), and "vapor canister vent solenoid" (next to fuel tank), as well as replace some cracked evap hoses under the hood. Then erased the code to see if it would come back.
Then I successfully drove it to work the following day, and trying to leave, it again, wouldn't start. It has since, driven a couple times, starting intermittently, but code has not come back.
Some noteworthy observations:
- It seems it starts right up if enough time has passed sitting (7-12 hrs)
- It seems to definitely starts right up if parked at a significant incline, facing uphill (this was confirmed when being mounted on a tow truck at an incline, immediately after waiting several hours for it to start - it started.)
Based on these observations, I'm speculating that the computer won't engage starter motor because fuel tank/evap system sensors detect excess pressure somewhere?? I don't really know, and I'm not sure how to proceed. I would really like to prevent paying for unnecessary system-wide diagnostic, and it seems like I may have enough information to find a lead. PLZ HALP!
Thanks in advance, you the man 😎
- Isaac
While diagnosing the intermittent no crank condition, put the small evap leak out of your mind. The no crank condition is almost certainly related to the battery, the cables, the starter, neutral switch, ignition switch or grounds. Load test your battery and alternator. Make sure your cables and battery post connections are corrosion free and tight. Make sure your grounds are good. This video from Scotty has some helpful tips. Good luck.
https://youtu.be/TSE0fOrujW0?si=j2gVAzvkxhvezlSY
Could also be the starter relay
@oldandy Thank makes good sense, thank you! Great video referenced. It must have been a coincidence that it happened the first time at the gas pump. If it is just electrical connection, I wonder why it would start consistently after sitting overnight
It might be coincidence or it might be that the problem component is affected by heat sometimes. A relay can stick when hot then work after cooling off. Starters can fail when hot but work after cooling off. Intermittent issues can drive you crazy. Two years ago I had one that I resolved by replacing the negative battery cable, which looked fine but had corrosion under the sheathing. Started fine, then didn't, then did, then didn't, doing that for days. You will figure this out.