PWM boost control and not holding boost?

justin · Post by **justin** » Wed Apr 29, 2009 6:45 pm

Ok so I finally have some results with the new Hondata solenoid. Weather has been retarded here last few weeks with snow then 70's then snow then 70's so I haven't really fine tuned the solenoid duty cycle yet.

But, I have had it set and been doing tests going to/from work while gradually upping the duty % everyday. It seems to be working properly again as I am holding boost to redline in 3rd (so far up to 20psi on gauge) and it is spooling like it should. No datalogs yet but maybe this weekend if weather stays dry.

In reply to crucian, I did check for boost leaks all around when I put in the new solenoid. In fact, I actually replaced all my vacuum lines for the WG and solenoid and re-safety wired them all. I also took apart my WG and checked the diaphragm as part of my earlier troubleshooting before I got the new solenoid.

Anyways, hopefully I can get some datalogs this weekend and get it dialed in. Here are some pics of my old solenoid and the new one as well...they are identical to the eye except for a number and the stamp on the blue part. I can only guess that my old solenoid took a crap at some point since when servion tuned it it was working fine...

Hondata branded solenoid is on the left:

Justin

justin · Post by **justin** » Fri May 15, 2009 8:20 pm

So yea, guess my luck didn't last because the same problem just started again. I haven't changed a thing since my last post where it was working, and now the solenoid is not holding boost anymore. It just goes straight to boost cut with no sign of the wastegate opening.

So, 2 solenoids, same problem. Starts out working fine for a week or so then performance deteriorates and just plain stops holding boost. Are solenoids vulnerable to heat or something? I can't think of anything that would cause them to go bad except excessive heat, mine is mounted in front of the engine bay right next to my half radiator.

Justin

Post by **Spunkster** » Mon May 18, 2009 11:20 am

If nothing has changed you can rule out the software as the culprit. You either have a wiring issue, a plumbing issue or the solenoid is being subject to extreme temperatures and is getting damaged.

justin · Post by **justin** » Mon May 18, 2009 11:57 am

Spunkster wrote:If nothing has changed you can rule out the software as the culprit. You either have a wiring issue, a plumbing issue or the solenoid is being subject to extreme temperatures and is getting damaged.

It is wired up and plumbed exactly to the Hondata guide in Smanager help. It is mounted on that vertical brace in front of the car, right next to radiator and in front of manifold/wg. I was kinda of thinking it might be too hot right there. The solenoid going bad is the only thing that makes sense, isn't it?. The other parts, wastegate, wiring, plumbing, have done their job fine when each solenoid was new.

Is there anyway to test a solenoid out of the car to see if it's good? I guess I will have to try another one and mount it in a place further from the heat areas.

Justin

justin · Post by **justin** » Wed May 20, 2009 6:42 pm

Got a tip from another person on different forum. Problem is solved, turns out the filter on the solenoid clogged and was not releasing air quick enough causing the wg to stay shut. This explains the gradual performance degradation with each solenoid (as they slowly clogged up), since my old solenoid and Hondata branded 'noid had the same flat faced filters.

I took the filter off today, again without touching software since my last posts, and the boost control is working again holding boost.

Justin

Martian · Post by **Martian** » Thu May 21, 2009 4:12 am

would it be a good idea to make a new larger filter for it? I've been on an mbc again for a while, and this was a reason for doing so. If yours is figured out I might switch back.

justin · Post by **justin** » Thu May 21, 2009 10:08 am

Martian wrote:would it be a good idea to make a new larger filter for it? I've been on an mbc again for a while, and this was a reason for doing so. If yours is figured out I might switch back.

Josh,
I've heard you don't need to run the filter at all. I will see how it goes as I drive more. I would have switched back to an mbc by now too with all the problems I've had with this, but the boost by gear is a huge bonus on the street since I DD this car.

Justin

Martian · Post by **Martian** » Thu May 21, 2009 4:09 pm

Nah, you just need a bigger turbo :)