1990 760 Turbo wagon dies at random!

This is going to sound like a repeat of an earlier situation with another car.

We have a 1990 760 Turbo (intercooler) wagon with 147k miles. The vehicle will die at random, stop lights, freeway, city streets, etc. It will usually start up once I coast to a stop, or it will take a minute or so before it starts. It can go months before it dies, and then it may die every day for a week or so.

I?ve had 3 different mechanics try to solve the mystery. So far, we have replaced:

System relay Air Mass Meter Spark Plugs Cap & Rotor Plug Wires Speed sensor Power Amp Ignition TB Gasket (during cleaning I?m assuming)

No luck with fixing the problem so far. Want to take a crack at it?

I just checked the fault codes and they read 2-3-2 & 3-1-1.

Thanks for the help!

Reply to
Stroller
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2-3-2 suggests fuel supply anomaly and 3-1-1 suggests Speedometer signal absent. It is possibly curable by thoroughly cleaning the inlet tract (from filter to manifold including Idle Air Control Valve). This is a two yearly maintenance job. Also check all connections to and from ECU and ICU plus all sensors that feed to the ECU/ICU.

Cheers, Peter.

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Reply to
Peter K L Milnes

My volvo had a faulty car alarm that caused the car to cut ou when you were driving it.

Reply to
Brendan Griffin

Wild guess, based on the lack of pattern and the random amount of time before it restarts - crank angle sensor (or whatever the Hall effect device is called in the 1990 765T). It is infamous for doing that and being the very devil to catch in the act. One clue - if the tach kicks when you try to restart but the engine doesn't fire, it isn't the Hall effect dealie or anything in the ignition. Has the fuel pump relay been resoldered or replaced yet?

Mike

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Reply to
Michael Pardee

I had a hot-start/run problem in my 1989 760 turbo that proved to be the "charge air overpressure switch". Basically, it's a vacuum switch that cuts power to the fuel pumps if your turbo is blowing too much boost.

It's the first powered link in the fuel system after the ignition switch, and if it's faulty it's a real bugger to diagnose. I just bypassed it with two alligator clips and a scrap of wire, and the car starts and runs fine now. IPD doesn't sell it, and my local Volvo dealer was no help in trying to order one.

The Haynes manual (which only covers up through '88, I believe) had the part living up under the dash around the brake pedal cluster, but by my 1989, the Volvo engineers had moved it to a strap on the coolant overflow tank under the hood. I suspect it was the dramatic heat cycles that killed it.

Best of luck!

--Dale

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Reply to
Dale James

"Brendan Griffin" wrote: > My volvo had a faulty car alarm that caused the car to cut ou > when you were > driving it.

Thanks for the input! No alarm system is the Volvo, so I can rule that out.

Reply to
Stroller

"Stroller" wrote: > This is going to sound like a repeat of an earlier situation > with another car. > > We have a 1990 760 Turbo (intercooler) wagon with 147k miles. > The vehicle will die at random, stop lights, freeway, city > streets, etc. It will usually start up once I coast to a > stop, or it will take a minute or so before it starts. It can > go months before it dies, and then it may die every day for a > week or so. > > I've had 3 different mechanics try to solve the mystery. So > far, we have replaced: > > System relay > Air Mass Meter > Spark Plugs > Cap & Rotor > Plug Wires > Speed sensor > Power Amp Ignition > TB Gasket (during cleaning I'm assuming) > > No luck with fixing the problem so far. Want to take a crack > at it? > > I just checked the fault codes and they read 2-3-2 & 3-1-1. > > Thanks for the help!

I?ll try cleaning the inlet tract this weekend!

As for the fuel pump relay, I don?t think that has ever been changed. Where is this located?

The Volvo just quit on me this morning at a stop light. Just died. It did start on the second try. Total time that elapsed was about 20 seconds. No check engine fault this time. I had been on the road for about 35 minutes when it happened.

Reply to
Stroller

The fuel pump relay on your 760 is behind the passenger side kick panel on the side of the Centre Console. It sits on the relay panel which is mounted vertically. The Fuel pump relay is The one on the top row between the top of the double relay (headlights) and the foremost relay (Central Locking system).

Cheers, Peter.

Reply to
Peter K L Milnes

If it is the same location as my '85, it is in the center console. Remove the ash tray and ash tray mount, exposing the fuses. The relay is on the far left side (as you sit in the car); a rectangular white plug-in module in the second row back (toward the nose of the car). They are notorious for intermittent solder connections in the circuit board inside.

Mike

Reply to
Michael Pardee

Sorry Mike but this is a 1990 (post facelift) model. The fuses are in the end of the dashboard and cannot be accessed if the driver's door is closed and the relays have their own special place as I have already described to the gentleman.

Cheers, Peter.

Reply to
Peter K L Milnes

Thanks for the info, Peter! Next time I'll know (if I don't forget between now and then.)

Mike

Reply to
Michael Pardee

"michaeltnull" wrote: > "Peter K L Milnes" wrote in > message > news:d3mqij$8sr$ snipped-for-privacy@sparta.btinternet.com... > > Sorry Mike but this is a 1990 (post facelift) model. The > fuses are in the > > end of the dashboard and cannot be accessed if the driver's > door is closed > > and the relays have their own special place as I have > already described to > > the gentleman. > >

Thanks for the help!

I replaced the Fuel Pump Relay this evening. When I pulled the plastic covering off the old one, I did notice a small crack in one solder joint. We shall see if that fixes the problem.

Stroller (aka Brian)

Reply to
Stroller

Something like this?

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Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs (among other things)

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Reply to
Boris Mohar

Reply to
John Robertson

Sorry John but it doesn't as it is harder than electricians solder and is more affected by vibration.

Cheers, Peter.

Reply to
Peter K L Milnes

"Stroller" wrote: > This is going to sound like a repeat of an earlier situation > with another car. > > We have a 1990 760 Turbo (intercooler) wagon with 147k miles. > The vehicle will die at random, stop lights, freeway, city > streets, etc. It will usually start up once I coast to a > stop, or it will take a minute or so before it starts. It can > go months before it dies, and then it may die every day for a > week or so. > > I've had 3 different mechanics try to solve the mystery. So > far, we have replaced: > > System relay > Air Mass Meter > Spark Plugs > Cap & Rotor > Plug Wires > Speed sensor > Power Amp Ignition > TB Gasket (during cleaning I'm assuming) > > No luck with fixing the problem so far. Want to take a crack > at it? > > I just checked the fault codes and they read 2-3-2 & 3-1-1. > > Thanks for the help!

I also have a 1990 760 Turbo wagon with the exact same problem. Mine has 99.6K miles on it. It was serviced by a dealer until two years ago when I bought the car.

This morning, running at 30 mph, the engine died. I put it into neutral and tried to restart as I was rolling but it just kept cranking. I was able to pull to the side of the road and stop. After

10 seconds, I cranked it and it started.

Another problem, which I thought might be related, is that you have to crank the engine for about five seconds before it starts. However, it you crank it for two seconds, then wait two seconds, it will start immediately.

I am going to pull the diagnostic codes now and I?ll let you know if they are the same ones you got.

Regards, Jim O?Connell

Reply to
jdoconnell

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After the most recent stop, I checked the codes. On port 4, a got no code (1-1-1); on port 6, I got 1-4-4

It seems to me this must be a Volvo fault. A similar situation occurred with Fords in the late 1980s. The problem was an "ignition module", which had been mounted on the side of the distributor. It was a solid-state film device and, as it aged, heat rising from the exhaust manifold would cause it to malfunction, causing the engine to die.

I spent over a thousand dollars at a Ford dealer trying to determine the problem. Ultimately, it was a $40 part that I installed myself.

Reply to
jdoconnell

bad fuel pump relay???

Reply to
Al Dente
1-4-4 states " Load signal from fuel injection system absent. Did you check all codes available on 2 (fuel) and 6 (ignition)? Port 4 is not normally used in fault diagnosis of ECU/ICU problems.

The Volvo ignition power amplifier suffers similar problems to the late 80s Fords. It is mounted usually at left front of inner fender and suffers corrosion of the connector's connections and poor grounding (of both heat sink and wire connection.

All the best, Peter.

700/900/90 Register Keeper, Volvo Owners Club (UK).

Reply to
Peter K L Milnes

"Peter K L Milnes" wrote: > 1-4-4 states " Load signal from fuel injection system absent. > Did you check > all codes available on 2 (fuel) and 6 (ignition)? Port 4 is > not normally > used in fault diagnosis of ECU/ICU problems. > > The Volvo ignition power amplifier suffers similar problems to > the late 80s > Fords. It is mounted usually at left front of inner fender and > suffers > corrosion of the connector's connections and poor grounding > (of both heat > sink and wire connection. > > All the best, Peter. > > 700/900/90 Register Keeper, > Volvo Owners Club (UK). > > > > > After the most recent stop, I checked the codes. On port 4, > a got no > > code (1-1-1); on port 6, I got 1-4-4 > >

Peter is correct, I checked on Port 2, not 4,---but got a 1-1-1. I got the 1-4-4 on Port 6.

Does anybody else have any experience with the Volvo ignition power amplifier? What does it look like?

Reply to
jdoconnell

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