muddy

Hi,

For nearly 2 years now I have been driving my My93wrx not knowing that it was only producing 7psi boost. I found this out in february when I went on my first rolling road.
Anyway, the nice blokes at Roger Clark motorsport fixed the problem today, apparently all the vacuum hoses were connected up incorrectly.
So I have now got 14psi max, leveling out to 12psi, which I recon is about right.
I am chuffed to bits, It's like having a new car again.
My concern now is that I have a couple more problems.
There is a ticking sound (tick,tick,tick) coming from the dashboard. I think it could be the speedo cable making the noise as it increases with speed.
I took it off the back of the speedo and it was still ticking.
If it is this, why is it ticking when it is connected.
Does anybody have any ideas!.
Also on the way back from Roger Clark's the engine would feel like cutting out, when putting my foot down, as if it was hitting a limiter.
This happened nearly every time I put my foot down, seemed like it did not matter what gear I was in.
Would this have any connection to the speedo cable.
I know that a dodgy speedo cable results in the engine being restricted to 4000rpm.
But the check engine light has not come on.

Any help would be much appreciated.
It seems that I have fixed one problem and gone to another.

Muddy

SecretAgentMan

Yo Mudd!

It sounds like your car is overboosting, and the ticking biz sounds like the wastegate solenoid, which from what I've heard is no biggie.

Have you got a boost gauge in the car? Then it's easy to see if it's overboost (it should peak high, drop like a stone, and come back to normal), which should be easily solved with restrictors (properly applied by a pro that is).



/Jerry

PeeVee

iTrader: (1)

Hi Muddy

I would agree with Jerry on his diagnosis of your cutting out problem, It certainly sounds like the Overboost cut is coming in.
With regard to the ticking noise from behind the dash, I would assume that your Speedo has been converted to read in Mls rather than Kms. On the early cable driven speedos this was done by fitting a miniature gearbox to the cable, halfway between the gearbox & the bulkhead. It is not uncommon for these to tick as they rotate.
When you disconnect the cable from the Speedo head, the cable itself is still rotating, so your noise will continue. If you would like to prove this theory then disconnect the cable from just above the gearbox and go for a short run. You may find on road test that the check engine lamp will come on & cause a lack of power, but don't worry cos it will go out again when everything is reconnected.

Hope this helps
Phil

firefox

A trick used by some owners/garages/importers to get around the overboost problem when they are selling it to bypass the boost solenoid and just plump the wastegate actuator direct into the manifold...so the car only runs about 8psi.

I've seen this on 3 cars now.. and the owners didnt realise.

I agree with Phil on the noise...sounds like the reduction gearbox in the speedo cable.

J.

muddy

Thanks for the replies.

Jerry,phil,firefox-

How you doing!!.
The ticking is definatley the speedo cable. I had been driving quite hard yesterday, so I think it might not cope with the heat very well, I had a drive this morning and it was OK, not ticking.
I'll try and see if I can lubricate it somewhere, or get a new cable or something!!.

Is this gearbox thing metal and sits just to the left of the clutch resivour.

As I went out this morning I booted it a bit, ok through 1,2,3 hitting about 10psi, 4th and 5th was the problem, deciding to jolt me when it decided to cut off again. It reached 14psi and dropped to 12psi.
So I recon your right about the overboosting.

Firefox, that sounds familiar as I have been driving for 2 years on 8 psi and did not know it!!!.
And it so happened when they reconnected everything the way it should be, it overboosts!!!!!!.

I know that fitting restrictors will cure the overboost problem;
But what will it do to the performance!!.

It's taken me 2 years to get the correct performance out of the car and now I might have to consolidate losing some of it!!.

Thanks again everyone.

Muddy.

[This message has been edited by muddy (edited 01 April 2001).]

Bob Rawle

Muddy, remove the pipe from the bottom of the boost control solenoid and check that there is a 2,0mm restrictor fitted, if not then thats why it overboosts, the rrestrictor should be visible by looking into the end of the pipe that was attached to the solenoid, or you should be able to feel it in place when the hose is warm.

If its not there its a standard part on a MY94,95,96 UK car so you can get it from a "friendly" dealer.

Bob

muddy

Cheers Bob,

I'll have a look tomorrow.

Muddy.

muddy

I have just had a look for this restrictor, but am none the wiser.
I know that the boost control solenoid is on the drivers strut, but the wastegate solenoid is there too (I think!!) which one is which!!.

Would a broken boost control soleniod cause this overboost problem.

Cheers

Muddy.