solenoid vacum pack

[FD Dave]

was just wondering if anyone has ever managed to replace an individual solenoid in one of these?http://www.rhdjapan.com/mazda-oem-kouki-unit-vacuum-solenoid-housing-fd3s-56016

iv been told one solenoid is faulty and you can only buy them as a whole which is about £350 from japan, thing is they also sell the solenoids individually so i presume you can just change one, but i dont know how hard it would be? difference in cost would be £350 compared with £45 so any help would be much appreciated.:InLove

[andrewrx7]

Yes, I had a go a couple of years ago. It is possible, but you need to be careful when opening the solenoid pack up, and a little brave! I had a second hand pack to hand, so was able to mix and match the solenoids to give a complete working set. I think I also changed the check valves at the same time. After all the hassle, I still didn\'t fix the problem and just bought a replacement pack from RHD anyway. Only got stung for about £20-30 taxes etc all told, so got off quite lightly. There was a very good write up for taking it to pieces, on one of the FD forums (in Aus I think), but sorry, I can\'t find the link anymore.

[FD Dave]

thanks for the reply, iv ended up just ordering one also.where did you buy your replacement check valves from? What problems were you experiencing with the faulty solenoid?mine keeps dumping boost in 3rd 4th and sometimes fith.

[andrewrx7]

Sorry, but this was a couple of years ago, so I can\'t really remember what the exact symptoms were. Juddery or lack of boost, I think. I did find one or two solenoids were not good, and interestingly, one of the tracks within the actual housing was leaking air to. The check valves were the good old Viton ones that people refer to on a regular basis, bought from a guy called Dale Clark in the US (via RX7Club forum)! Search this forum for Viton check values, there will no doubt be a link somewhere for other suppliers or just look on Google.

[FD Dave]

Well me and mate changed the unit over today,went for a test drive and surprise surprise exactly the same problem. £350 down the drain and still no idea what the problem is, nice diagnosis re worx lol. Only thing i can think of is a check valve which i took off which was really hard to blow through which is in one of the lines which pressurises the vacum pack. Im also thinking that it could be the solenoid which controls the wastegate.

Symptons are the car has an intermittant boost fault and keeps dumping boost pressure out the wastegate under wot.it seems to boost in first most the time and sometimes 2nd 3rd etc and then other times it will boost up to .5 bar and then start dumping  or it just wont hold boost at all for whatever reason. Im thinking if it was a split hose then it wouldntbe boosting at all. Thing thats wound me up most is reworx charged me £60 to semi set up my boost controller and diagnose the problem, so where do i stand now with them?dont want them charging me again for a wrong diagnosis and waste yet more money.

[Jit]

Like I said on another thread before, I didnt think the solenoid pack was your problem. It may well be a check valve on the box at the front of the engine? Have u had a look at that?

[FD Dave]

Yeh Thats the one im talking about which i checked earlier, it runs to the vacum chamber at the top m the engine below the strut.

[Jit]

yeah when that check valve goes 2 way, it can often cause symptoms similar to what you described. Change it out and see if it makes a difference! Shame you spent so much on a new solenoid pack, if Id known before you ordered it, id have lent you one which I have which i know 100% works fine!

[FD Dave]

it doesnt flow both ways,  if anything it seems blocked when i try toblow through the direction of air flow, would it be causing the wastegate to open?woild you mind still lending me one please and if it works id give you some momey for it?yeh i know it really sucks but thats what you get for trusting other people i suppose, camt really blame them too much as it was only their opinion.