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APC solenoid noisy

1383 Views 3 Replies 3 Participants Last post by  jmmassheder
I have a 1990 model year 2.0l Carlsson (cdcalssson was a previous owner).

When cold, I get a lot of noise from the glovebox area - if I get heavy with the accelerator. I assume this is the APC solendoid. Sometimes the noise seems to come from the driver's side, where I think the pressure sensor is.

When warm, the noise happens at greater revs.

I've replaced the "vacuum" tube but this hasn't made any difference, any ideas?

The boost guauge goes into the red for several seconds before it backs off.

Once, after disconnecting the battery, the car felt the most powerful ever, boosting half way into the red. It then backed off the boost to behave as before.

Does anyone have ideas how I can maintain the more powerful behaviour?

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The buzzing is the gear shift linkage There is a modification somewhere to the shift mechanism which can be required to fix it, but it's too late to dig it out now

However I think in most cases, it indicates worn engine mountings. In my case, changing the tranmission mounting bush and the easier of the two top dogbone bushes fixed it for me.
If it only lasts for a couple of seconds, and stops when the APC backs off the boost, it could be pinking.
Well, it is a while since my original post but I'm following up in case it's useful for the record.

The APC solenoid got noisier and then there was obvious blowing from the exhaust manifold. Some of the studs were broken (they have been for a couple of years).

On having the manifold gasket and studs replaced I can nolonger hear the APC solenoid. Also the faint turbo whistle has gone. (When I first got the car I mistook the turbo whistle for an emergency services vehicle siren in the distance!)
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