Bosch +4 application WARNING 99 Toyota 5VZ5E V6

Group,

This is a general heads up to owners of Toyota trucks, vans, or cars with the 5VZ5E V6 engine considering a tune up using Bosch +4 spark plugs.

AVOID'em!

Save yourself miles of aggravation and use factory Toyota Denso K16TR11 plugs.

In the first 50 miles of using the Bosch +4's, I experienced the following;

1. poor acceleration / power at highway speeds
2. rampant misfires on accelleration; sputters, engine stumbles, etc..
3. Noticed lack of passing power at highway speeds.
4. Intermittent MIL indicators after misfires.

If you are a DIY'er or are planning to have a shop change your plugs, make sure you demand factory Denso K16TR11 plugs for your 3.4 Liter V6.

After 50 miles, I pulled the Bosch plugs and replaced with factory Denso plugs.
Engine performance is smack dab back to where it should be. No hesitations and full power on accelleration.

Plug wires, fuel filter, air filter, throttle body, and MAS sensor clean were also performed before the Bosch and later Toyota Denso plugs were installed.

Unfortunately, it seems the major national aftermarket parts distrubutors are favoring the Bosch products. If your driving Japanese, avoid em.

If you're already stuck with a set like me, Bosch +4 is offering a money back guarantee if they don't perform. Details are available at;


http://jobs.boschusa.com/media/pdfs/PT_4_GTEE_WEB.pdf

 

Not just Toyotas mate! My old Ford and Dodge were the same way with Bosch. I find Bosch to be a junk plug and always go with OEM plugs. I had the same problems installing Bosch's as you did.

 

With the money back guarantee, they must have dump truck parked under their PO box in Michigan.

Wonder if I'll ever see the $40 back?

Cheers!