MR HYD

Hi,

I have searched but the issues listed seem different from what I am experiencing. Sorry if I have missed something.

No boost, (0mark or just above ) and then 4500 starts to come alive and then full boost and goes well.

Just put in new air filter but stock replacement. Filter didn't look like it had been replaced for a long time. Only mod is exhaust after cat converter.



Any help would be appreciated

sinCITYseven

Check bacuum lines and intake plumbing

Shifta

iTrader: (1)

Hey there, what type of rx7 do you have?
I'm assuming an fd being twin turbo?
If so what series is it?
It can be a number of things usually to do with the vacuum system - vacuum lines, solenoids, actuators etc.
As you've probably read the rubber hoses get old and brittle and can split causing a vacuum/pressure leak.
If it's a solenoid related issue (series 8?) you should take off the upper intake manifold and resistance test the solenoids with a multimeter. (Mine is a series 8 and it had a similar problem but low boost from primary instead of none, it was a faulty turbo control solenoid)
It can also be a sticky actuator.
Have a look around using the search bar for twin sequential turbo problems, testing solenoids etc. there is bound to be a massive thread about it

NZ7

Mines like this. But that's because they used a link computer and to make it work they opened all the actuators and welded them so I go from no boost to 4500 revs full boost and no traction lol.

Easy way to tell is if u jack the car up and under neath on ur in take pipes ull see some sorta like bolts sticking out if they have welds or tack welds on them that's what it is.

So instead of low boost in low revs then high boost they are both spooling at low revs the. Big revs both kick in

Shifta

iTrader: (1)

This is true, they could be running parallel instead of sequential...
Has this problem been there since you first got your rx7? Or did it start some way through owning it?

MR HYD

It's a 99 series 8. I had checked the hoses but will recheck. It's only just started so I was thinking it might be a actuator problem.

Thanks I will run through the suggestions. Fingers crossed

With your solenoid issue did you just replace?

Shifta

iTrader: (1)

Yeah, i had a turbo control solenoid (the one bolted to the air control valve underneath the upper intake manifold) that read as an open circuit (faulty), and the purge control solenoid (emissions related and people usually just leave it apparently).
I replaced them both as well as all the vacuum lines to silicone.
I got both of them from Atkins rotary specialists online, cheaper price, ships world wide and it turned up pretty quick to Australia

MR HYD

Ok, so I rechecked the lines and they seem ok still. I have noticed the charge actuator arm is still out under idle so I am picking this is a vacuum problem. Could this be the solenoid? And how do I check if they are faulty? (Open circuit?)

Shifta

iTrader: (1)

to test a solenoid, you just need a multimeter and set it to resistance mode. unplug a harness from the solenoid and put the positive and negative (doesn't matter what way because its resistance) on each metal tab. They should read at 37-41 ohms of resistance when cold and reach up to 45 ohms of resistance when warmed/hot. Higher than 50 when hot or 41 when cold indicates probable failure. Open circuit or values such as 80ohms=failed.

I'm not sure if there's a full 'how to' on the series 8 on here, not meaning to forum jump or anything, but at the bottom of this page will be a file called "S8 Solenoid Box Rebuild, Vac Line replacement."
download this, it's what i followed when doing my vacuum lines and solenoids, it will tell you everything you need to know

FD-RX7 Enthusiasts Forum

MR HYD

Replaced all vacuum lines over the weekend just in case and the solenoid was indeed faulty so will get a new one. Thanks for your help.

Shifta

iTrader: (1)

No worries
Glad I could help

MR HYD

Ok so new solenoid installed but still no joy

Also new plugs and leads went in

I am guessing the other solenoid box has an issue

Shifta

iTrader: (1)

hmm, did you check all of the solenoids?

RotaryEvolution

iTrader: (30)

and do you still have the restrictor pills in the vacuum lines to the actuators? they are commonly omitted during vacuum line jobs and result in low boost/laggy transitions.

another thing to check is physically check the primary turbo by removing the intake duct to it and checking its free play and see if it spins freely.