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Power Stage Amplifier Story

Help, Advice, Owners' Discussion and DIY Tutorials on all Volvo's "mid era" rear wheel drive Volvos.
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shoulder dweller
Posts: 3
Joined: Tue Feb 09, 2010 4:38 am
Year and Model: '93 940 wagon
Location: Fremont, CA

Power Stage Amplifier Story

Postby shoulder dweller » Tue Feb 09, 2010 4:58 am

So, I'm new here, but I've been peeking in for a while trying to diagnose a problem that my 93 940 wagon was having. Thought I'd share the result as a way of "giving back."

The car stalled one night as my wife drove home from work. She had taken an exit off the freeway and it stalled. The stalling involves all dash lights coming on, tach drops to zero, followed by a pretty quick restart and seemingly problem free ride home. I should mention that this wagon is an automatic, so I was not able to simply drop into neutral to start. Had to pull completely over, stop, put trans in Park, and then start.

Well, the stalling became more and more frequent, especially at stop lights, turns, any time when the accelerator was not depressed... but occasionally when accelerating, as well. I had no voltage meter, still don't, and I don't have confidence in my ability to use one, but I think the time has come.

Anyway, I finally brought the car to Scandia Volvo, near Fremont, CA, where they hooked me up quickly. $370 later, but same day service. They were very helpful, too. Explained how they diagnosed the problem, etc. Basically, they had a hunch and used a "good" Power Stage Amplifier to swap out mine and let the thing idle for half an hour. When it did so without stalling, they had their man, so to speak.

The power stage amplifier is located (on this model) next to the air filter. It is mounted on the driver's side fender wall, behind the driver's headlight.

(it is also called the ignition amplifier)

As a matter of fact, there are 4 available on ebay right now. They say "Buy now" for $10.99, which seems like a heckuva deal. I wish I wasn't so broke, I would grab a couple for myself for future testing/replacement. This is the link to the ebay sale: ... 0007r18720

So, I hope this helps somebody. I'll probably be back eventually with some ridiculously ignorant questions, so I felt it best I throw my 2 cents in first.


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Year and Model: 855, 1995
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Re: Power Stage Amplifier Story

Postby billofdurham » Tue Feb 09, 2010 6:23 pm

Welcome to Matthew's Volvo Site.

Thank you for sharing your experience. It is a great start to your membership and any "ridiculously ignorant questions" won't worry us. If you knew the answer there wouldn't be a question. :wink:

Work was good - retirement is better.

1996 850GLT 2.5 20v Estate Manual.
1995 Peugeot Boxer 2.5Tdi Autosleeper.
1984 244DL, Manual, Beige.
1987 744GLE, Manual, Green.
1991 960 3.0 24v, Auto, Silver.
1994 940T Wentworth, Auto, Blue.

shoulder dweller
Posts: 3
Joined: Tue Feb 09, 2010 4:38 am
Year and Model: '93 940 wagon
Location: Fremont, CA

Re: Power Stage Amplifier Story

Postby shoulder dweller » Wed Feb 10, 2010 9:06 am

Thank you, Bill. I'll keep that in mind when I've got time to tinker with the Wagon. I've got a number of projects in mind for her, including updating the relay for the intermittent wipers, getting my dome light to work properly, getting a new headlight housing (passenger's) and a new driver's side turn signal cover (I think the housing I have is fine... it's just the plastic "lens" part that is missing. Oh, and maybe adjusting the emergency brake cable... I'd like a bit more tension, but I think I may want to check the rear brakes first.

All in due time.
Thank you for your encouragement!


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Year and Model: 760 1988
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Re: Power Stage Amplifier Story

Postby lummert » Wed Feb 10, 2010 11:15 pm

I don't remember you saying if the car is a turbo, but after looking up the ignition module at two parts places, what you have here is a learning experience. The ignition module at Volvo is listed at $156.39 with an MSRP of $190.72. A bosch ignition module at FCP Groton lists for $89.99 and at Eeuroparts for$79.98. I now carry a spare ignition module in my glovebox. If the dealer just tried replacing the ignition module with a known good one and that was the first thing they checked then that diagnostic charge must have been a doozy.
1988 Volvo 760 Turbo Wagon

shoulder dweller
Posts: 3
Joined: Tue Feb 09, 2010 4:38 am
Year and Model: '93 940 wagon
Location: Fremont, CA

Re: Power Stage Amplifier Story

Postby shoulder dweller » Thu Feb 11, 2010 8:21 am

Yeah, and it wasn't the dealership. It was like $113.00 for diagnosis, $180.00 for the part, $70.00 for "installation," which, as far as I know, was plugging in the new piece, but probably refers to labor - the time to watch it idle successfully with the back up piece in place.

And I wish I had the money to keep backup relays, etc in the car at all times.

PS - not a turbo.

PPS - a very good learning experience.


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