I am new to the forum and am having problems with a '95 960. Engine was running bad and would shut off from time to time. I did some checking and found that the fuel filter was almost clogged (I coud hardly blow through it). I replaced the filter, started the engine and all seemed well for about 5 minutes. Then the engine started to run rough and shut off. It would not start up again. The fuel light was on so I thought it had run out of gas. I put appx. 5 gallons in and it still will not start.
I pulled codes on the onboard diagnostics. Codes are as follows:
Socket #1, 1-1-4
Socket #2, 1-2-3
Socket #3, 1-1-1
Any help would be appreciated, Jim

 

Socket 2 is for the engine, not sure what the other two sockets relate to, abs, trans or climate control?

Code 123: engine has no signal from the temp sensor.

I would check the plug first, it is located at the rear of the head, very difficult to get at, it is under the heater hoses. There are two temp sensors on this engine, one up front by the t-stat which powers the dash gauge, and the second one is at the rear of the head, which signals the computer, that is one you will need to get at.

If that does not fix it, you may have to replace the sensor. Draining the coolant would be required.

But check the plug, clean it if you can, and see if that does the trick.

Usually though, when the signal is missing the computer notes that as a fault and runs a program that simulates engine temperature by time running. So you may have other issues, like a vacuum leak, a crack in the rubber air intake ducting, a leaking intake manifold gasket in combination with the fault code.

Check to make sure your hose is on the idle speed motor, it is the small silver can attached to the rubber intake on top of the engine, there should be a small by-pass hose attached, be sure that is there.

DanR '94 964 353,000 miles (119,000 on the new engine)

 

Thanks for the info Dan. I will check all that you mentioned. If needed, is the sensor a dealer item? This is my sisters car and she has had it at several garages and they did all they could I guess. Thought I had it solved when I found the clogged fuel filter. I didn't mention before, but I found (2) black ground wires under the front of the car(1 attached to trans and the other attached to engine). They have what looks like a battery terminal on the other end(not long enough to connect to battery). I could not find where they attach, so I attached them with a bolt to the frame xmember. Is this Ok? It appears that a pan or guard is missing under there. I assumed that it must have had a connection for this.

 

I found this link to a document that explains how to pull the codes and what the definitions are for a 960. Hopefully it will help to define your issues.


http://volvospeed.com/Repair/a2.html

 

pturner, thank you for the link.

 

Have you tried to get the codes pulled with a OBD-II reader?

 

rspi, No I have not. Would this make a difference?

 

I have replaced the fuel pump, fuel filter, ETC sensor and plugs.
I have compression, plug fire, fuel pressure, injectors pulsing and no codes, but this 960 will not start-up.
Without any codes is it possible that the crank or cam sensor is bad? What is the blinking red light on the radio?
Any help would be appreciated, Jim

 

You may have nailed it. Cam Sensor bad. I had this problem with a Jeep. No codes, cranked over and over but no fire.

Radio blinking is just the security feature.

 

Actually, the engine will run with out a cam sensor, the ecu will run a default program that doubles up the fuel injection rate.

It will run, but be a little sluggish and fuel thirsty.

So, don't bother changing it, it will not help. Now an RPM sensor is another thing, will not run without that though. But if it was an RPM sensor, there would be no spark.

So, you have compression, did you have a compression test done? Do you have compression on all cylinders? Has the fuel pressure been measured with a gauge?

If you really have all that is basic for an engine to run, then you will need to look else where. Is the engine breathing correctly, blockage in the air filter, in the air intake, is there blockage in the exhaust, someone been messing with the car, timing off?

On the air intake there is a small rubber hose that fits into the idle speed motor, idle speed motor is fit into the rubber air intake, small silver canister. That small rubber hose connects to the intake manifold, sometimes that hose can be blown off by an engine back fire. Ensure that it is there. You may have a huge vacuum leak, Check those short rubber hoses that connect to each cylinder, look for cracks.

What caused the fuel filter to be blocked?

I do not think timing is off, because you claim there is compression, but if you are just using your hand over an open spark plug hole and cranking, that may not be enough.

Another thing that can happen with these engines, but only heard of it while it is cold outside, is the " lawn mower syndrome". A ice cold engine is started and run for only a few seconds, say to get the lawn mower out of the garage or move the car into the drive way, that sort of thing, the key is, it is only run for a minute or less. Then on the very next start, the engine cranks but does not fire up, the reason is the lifters over pump with oil, because it is cold, they do not leak down, because they are overpumped the valves or some valves do not fully close, no we are only talking hairs here in movement. The only remedy is to crank that engine over with your foot holding the gas pedal to the floor, hold the gas pedal to the floor shuts off the injectors while the engine is cranking. Eventually it will start to fire one cylinder cutting in at a time, this engine will run on three cylinders, so once three are firing, it will run, though the engine will seem to want to stumble out of the engine compartment, but it will not harm anything.

This event has happened to me at least a half a dozen times, before I figured out the pattern of behavior. Since then have read of many people going thru the same and there was a name for it too.

Crossed coils on the sparkplugs?

DanR

 

I ran a compression test and a leakdown test Compression on all cylinders is 175 to 190. Leakdown was close to 0% leakage. I do not have an adapter for my gage to actually check fuel pressure, but fuel hits the fire wall when depressing the shrader valve,
It's close to 100 degrees here so the lawn mower theory probably would not apply.
Thanks to all for your suggestions, Any other input would be appreciated.
Jim

 

After a lot of hassle with the volvo dealer, I finally got the right ect sensor (I won't bore you with the details of that fiasco)! This resolved my starting problem. Engine seems to run fine.
I checked codes again so I could clear the 1-2-3 code and now I have a 5-1-2 code (Oxygen integrator at max lean running limit). Could anyone tell me what this means and what to check? Does this have to do with the MAF?
Thanks Jim

 

I have (2) codes stored and cannot get them to clear.
1-2-3 and 5-1-2, They will not both come up when checking. In other words one code will come up and I wait for the other and nothing happens. I push the button again and the other code comes up. I press the button for 8 to 10 seconds and when I release the light will come on for about 6 seconds. I check for codes again and it's the same all over again. Am I doing something wrong? I disconnected the negative battery cable for a while and when reconnecred the codes are still there. Engine seems to run fine.
Any help woud be appreciated.

 

When doing your code read with the intention of erasing them you have to read the first code twice. Once that happens you will be able to erase them.

You are trying to erase after reading the second code, just push that button as if to read a third code, once the first code appears it should erase.


DanR

 

DanR, Thanks for the reply. What you suggested worked.
Thanks again, Jim

 

You still have a 512 code? Yes, is could have something to do with the MAF.


Here is the fault tracing guides info.

Fault sources - faulty 02 sensor signal, (could be a sensor, could be a wire)
high fuel pressure.

Symptoms are high fuel consumption and uneven running.

Check your fuel pressure while connecting and disconnecting the fuel pressure regulator vacuum line. Pressure should be lower with it connected.

Also check for vacuum leaks.


DanR

 

DanR, Thanks again for your response. I did figure it out. A vacuum leak was the problem.
Jim