I had a pair of EVOMS billet diverter valves installed June 2006 about 4,000 miles ago. My car is acting strange and has a hesitation, especially when shifting gears under full boost. There are no codes or check engine light. The car hits full boost but there is a hesitation and HUGE lag. How can I determine if the DV are functioning correctly?

BTW, brand new FR6 plugs were installed, new O2 sensors and the MAF was checked as well to no avail. My shop thinks maybe the drivers side turbo is going bad as there is slight play in the shaft. I think it may be the DV.

TIA,
Adam

 

Look at your valves once removed. Alot of times they get gunked up and need to be regreased or cleaned. This can cause problems opening up which would give you that lag. Once they find a way to get pushed open, that is why you are then making boost. I would recommend pulling them and looking. Before you blame a turbo on a little shaft play, but stock ones back in and see if that changes. If you need any help, give me a ring.

Thanks
Dan

 

Dan:

Thanks for the insight. What should the DV's be greased with? I do not recall any grease or lubrication upon receipt from EVOMS.

Also, do my symtoms listed above seem charateristic of a stuck DV?

Thanks,
Adam

 

What you will see is maybe some black build up. Degrease and clean the piston if you can pull the valve apart. Then apply a little grease around the piston. I dont know the technical name of the grease, but the guys in back here have some they put on lots of different application. You just want something that is light, not to thick, and to keep the piston moving good.

 

symptoms...maybe, try this first!

 

Dan:

Great. Thanks for all of the advice. Much appreciated. I will try this and hopefully it will cure the problem.

Adam

 

Alevine, the best way to test your valves is to use a hand held vacum pump with a gauge on it. connect it to the valve and pump it, the valve should hold 20 to 24 in/lb of vacum. Possible reasons for a valve not holding could be a worn or ripped o-ring or the valve peices could have come loose. A good cleaning and re-lube with white lithium grease wont hurt either.

Hope this helps!!

 

derek k:

Thanks for the info. I finally fot the car running well again after about 6 weeks or so. Changed the plugs, MAF, O2 sensors and all seems fine. I plan to clean the DV's next spring as a perventative measure and will use your instrucitons above. Thanks again.

Adam