Nightmare!

[D3S]

I bought some new check valves for the FD, thought an hour job wouldnt turn out to be 6 hours! Slowly start removing the pipes and crap the end snapped off the double throttle control valve (great) so knowing its a mare to get to i decided to remove all the UIM, alternator etc etc to get to the racks. So i finally got there replaced the vacume hoses, fixed the valve checked it all over. Put it back together and now it ticks over like a sack of poo, idles at 300-500rpm and hardly hits 0.5 bar of boost. Im well cheesed off, i followed all the diagrams and check the hoses went in the correct places and not im just lost what to do?! not sure if it will need new valves or what? Im thinking of just taking it to a rotary tuner and get them to look over it as its a pain taking it apart all the time Any local around berkhamsted (watford) area? or ideas what to do.

Cheers

Gav

[rx7veilside]

i learnt a long time ago only work on a car if i have to..as i am jinxed no matter what i touch i f--k it up..brakes/water pumps/power steering racks u name it i cock it up...i know it can be satisfying to do it urself but i end up stressed and tired and frustrated...i know the theory but fail on the practise side..unless u enjoy doing it get the garage to do it

[Martiny]

How did you repair the double throttle control valve?

Do you have an aftermarket Boost gauge that shows vacuum, too? This would tell us if there is a leak somewhere under idling?

There is a way of bypassing the double throttle control, I would start by doing that , (for diagnostic purposes, not as a permanent mod).

[D3S]

Well when it first snapped off, i super glued the nipple back on, while waiting for it to dry i changed the other vacume hoses. Went back to it, pushed the hose back on and the thing snapped again. So i took the valve out and noticed the glue had also blocked the hole, slowly drilled it out to clean the hole and then stuck it back on again with super glue this time check the hole was clear and it all went fine put it back on and well the rest is history so to speak. Would the double throttle valve cause rough idle and boost issues though?

Gav

[Martiny]

Well when it first snapped off, i super glued the nipple back on, while waiting for it to dry i changed the other vacume hoses. Went back to it, pushed the hose back on and the thing snapped again. So i took the valve out and noticed the glue had also blocked the hole, slowly drilled it out to clean the hole and then stuck it back on again with super glue this time check the hole was clear and it all went fine put it back on and well the rest is history so to speak. Would the double throttle valve cause rough idle and boost issues though?

Gav

Ok, I think you need to replace that valve, just for peace of mind. Get one from Andrew at Jimmy\'s. I dont think it will cause rough idling, unless your repair is letting air into the manifold somehow. It could cause your lack of boost, though. the throttles might not be opening, or you could be allowing pressure or vacuum to escape from the control system.

If you have rough idling, I would definitely suspect a leak somewhere. You\'re sure that all your little pipes have gone back where they should be? Especially those ones under the intake manifold?

[D3S]

Cheers for the info matey, well i have replaced all the pipes back where they should be, refered to the vacume hose diagram and all seems ok, one pipe i noticed was the large one next to the nipple for a boost gauge, that was split but not all the way through pipe, looks like it goes into the power stearing pump. What would happen if the valves where the wrong way round? i mean i know they arent but info would help. i cant think where there are any leaks on the UIM as i replaced everything. So then would it be valves all i can think.

Gav

[D3S]

Forgot to say as well, when you dip the clutch it nearly stalls i.e when your slowing down. Im lost now lol, what do you think, take it to someone that knows their way around it?

Cheers

Gavin

[Martiny]

I think the dipping clutch stalling is just a symptom of the poor idling. I dont think there is anything that goes form the manifold to the power steering. Do you mean the pipe that goes to the big black round thing? That is for braking assistance. Again, I would get a new pipe from Mazda , do you really want to have very little brakes on day as your coming up to a junction at 70 mph?

Is it the pipe shown below? Ask your Mazda parts man for F100 43 640A.

[Brett]

As you are only seeing .5bar and the idle is rough I\'d say your deffo looking at an air leak.  What condition were the hoses in? Soft or getting hard?  You may have a split hose now thats losing you your boost and letting the engine suck in unmetered air.

[Martiny]

Eeek!   I take back what I said about F100 43 640A, Mazda want £30 for it. Guys its the vacuum hose for the brake servo unit. Can I just use some fuel injection hose from Halfords, or is a pipe made for pressure not necessarily able to withstand vacuum, too?

[rx7veilside]

no u must use the factory hose as there is a one way valve in there to stop the servo seeing positive pressure when on boost it shd only ever see vac-negative pressure

[Martiny]

Ah, thanks.

[D3S]

Well, i replaced that servo hose for a test it didnt make any change, so im putting back the other hose after i noticed in had a one way vavle. Well maybe this would help the it, remove the double throttle totaly and have a single throttle? also replace all the solonoids and try to simplise the system? What do you think?

Gav

[Martiny]

http://robrobinette.com/

This site has some procedures to follow to help diagnose Boost problems. I would start here.

Removing the double throttle can be done, but Mazda put it in there to prevent the engine being driven hard when its not fully warm yet.

I think the solenoids and valves are very expensive from Mazda. It would be cheaper to get an RX shop to look at it for you.

If you hunt around the web, there are a few solenoids and pipes that can be eliminated.

[D3S]

Think thats the way forward, Jimmys has some solonoids so i will order some new ones, im going to replace those and make it a tad more simple, so i need the double throttle solonoid if im going to ditch the system?

Cheers

Gav