Just bought my 2nd 94 940 turbo after putting 100k on another 94 940. Very clean car. 95k on it. Just had to replace the intake manifold gasket. It was getting 17 mpg so I replaced the oxygen sensor about a month ago. It went up to 20 going 70 on freeways so there still was a prob someplace.

I live in upstate NY. Last week something new started to happen. it wont idle smoothly, and on acceleration it will shutter and feel like its about to stall. When I warm it up for 5 miles it gets a somewhat better, but still does its flutter thing.

This morning I went to leave and I had the radio on, so as I left I couldn't hear it fluttering as I left the drive way so I gassed it when I got no power and it stalled out. I tried restarting it and it will fire once every couple turn overs but wouldn't catch. After some testing i noticed if I left it for 10 minutes it would fire more often so i left it for 20 minutes. It almost caught after that one time. but then died. Gas is at 1/5 tank. It definitely smells like gas when i get out of the car. I can also hear the front fuel pump buzzing.

I am in the process of waiting for 40 minutes or so to see if it will catch and stay this time.

Any ideas of what the problem could be?

I have had the car for 7k miles. Its records indicate that it has only been driven 12k miles in the last 5 years.

Things I have done.

stuff i did when bought....
new spark plugs and wires
new air filter
new battery
cleaned air mass meter
cleaned throttle body(it was squeaky clean already)
checked all air hoses. No visible air leaks.
changed oxygen sensor 1k miles ago

Things I did when car died.
popped radio suppression relay on and off a couple times
popped air mass meter wiring off and on a couple times
popped all relays in and out to make sure they were set nicey
checked for air leaks.

 

How about the crank sensor on the flywheel. Unplug and replug.

 

I let it sit a few hours. No start.

Is the crank sensor coming out of the top of the transmission housing and plugged into a socket against the firewall near a air little check valve? I Yoinked that one. I might go get some dielectric grease and put it in all connections.

 

Ok, so i pulled a bunch of codes from the #2 socket which i believe is fuel. Nothing was in any of the other sockets.

232
113
231
221

were the codes available

going by this chart
http://www.troublecodes.net/Volvo/

1-1-3 is Fuel injectors.
2-3-2 is Lamda adjustment.
2-3-1 is Heated Oxygen sesnor(lean mixture/part throttle) 94-up.
2-2-1 is Heated Oxygen Sensor(Rich mixture/part throttle).

Maybe i screwed up installing the oxygen sensor? I would think it would start even with a bad sensor. I shall clear codes and see if any more pop up.

EDIT: this might be a better chart http://www.volvoclub.org.uk/faq/Engi...InjectionFault

EDIT2: tried starting the car with no oxygen sensor attached. Still no go.

EDIT3: Tried starting with air mass meter unattached. Still no go. Weird that I cant get anything out of it. I usually can pull off something. As soon as i can get someone to help me out I am going to see if i can hear the rear fuel pump working.

EDIT4: read someplace that the crank position sensor does come from the top of the bell housing so did find it. Also that if it was not working the tac would not follow the motor's rpm. when it does fire from moment to moment, the tac will jump upto where it should be. Can this hunch be confirmed?

 

Go back to basics. Do you have spark and do you have fuel. See if you are getting spark when you crank the engine over. Either use a timing light or ground out one of the plugs and see if you have spark. Also if you pull a plug see if it is wet with fuel. If dry then you need to start looking at the fuel system.

 

Pulled a spark plug. Got sparks an it smelled like gas and was damp.


Here is a pic.
imgur: the simple image sharer

Reading Spark Plugs

According to that and what I remember from the car when it was working properly and my other car, it should be more of a whitish color, not black. That chart indicates that it is burning too much gas.

I also listened for the sound of the in tank pump and it makes plenty of noise.

EDIT: Read someplace that there is a clear flooded engine mode. You press the accelerator all the way to the floor then turn the key on and off and it will just pump air through the engine. Is this true? that is a pretty cool feature.

 

Pulled the air box off hoping it is the idle air control valve and less restriction will open things up. It seemed to catch a bit more but it still wont hold. I also put gas in so that it is just below the half tank mark.

I'm going to pull the idle air control valve now and clean it. Maybe my brother will let me swipe some of his parts from his identical Volvo as well.

EDIT: Got my hands on my brother's nearly identical 94 940 turbo. Swapped out all the relays one by one and put dielectric grease on all contacts. No start. his car is weirdly missing a little blue relay in the middle and a bright yellow one in the far right corner. couldn't test those. Swapped out the radio suppression relay and put electric grease on contact. Nothing. put elec grease on air mass meter contact and crank position sensor contact. Nothing. unplugged air mass meter when trying as well. Nothing.

All that trying to start has mad a little difference. When I let off the key it will turn over once or twice on its own before dying. Also if i press the gas when trying to start it turns over quicker. I can also smell lots of gas when I get back out of the car. Not sure really what to do next. Maybe start swapping stupid things like batteries and stuff.

Will a bad oxygen sensor make it impossible to start?

Could the timing belt have slipped slightly?

I'm really stumped. Need an idea of what to check next.

 

Put more dielectric grease on the throttle body switch thingy, oxygen sensor, all the spark wires etc.

Swapped out the battery from bros Volvo which i know is fine for the hell of it and nothing.

Pulled off the pipe from the turbo so there is a straight pipe from the outside to the throttle. Turns over a lil better but not much.

Took each spark plug out and turned it over. every plug has spark and a fine mist blows out of the hole and if i stick the plug near said cloud, cloud goes bang.

I also put another 5 gallons of gas in. Its about 3/4 now. I'm getting nowhere.

My battery is starting to get low too. Need to swipe my bros battery when hes not paying attention.

My last 2 ideas are to clean out the idle air control valve, and to put that old oxygen sensor back in. Both of which I don't think would make it not start.

I need more ideas.

 

Swapped out the crank position sensor and nothing. I tried starting without it plugged in and it was way worse. Not a single firing from any cylinders.

Swapped out the ignition coil and nothing.

Took out the idle control valve out and couldn't make it open it with the pointy screwdriver I had. I Tried flipping it both ways. I then took a fathead screwdriver and jammed it into the edge of the flat side and worked it into the slot until it was a few 16ths of an inch wide. I then squirted some intake cleaner into it and let it sit for 10 minutes. When I tried opening it again with a screwdriver I noticed that it flipped open the other direction quite easily. I'm now not sure how jammed or if it was jammed at all.

So I swiped my brother's idle air valve from his car and installed it in mine but when I went to start it, the battery was dead. It's now 1 am and I am going to continue and get a jump in the AM.

I also greased up a billion more connections as I came across them and left the battery unattached so that the ECU will reset. Read that someplace......

If anyone has any more ideas for things I could test I have all the parts I could ever want to swap out. Just need ideas!

 

Got a jump No difference when trying to start it.

I then popped off the air intake pipe right at the throttle body and i pulled the hose off the idle air control that leads directly behind the throttle plate. I also did the same to my brothers car to see if his car would run like that and it did. I then had my brother squirt starter fluid in as I cranked. and no difference at all. I'm thinking electrical? I did get sparks before and I got an arc from the wire that goes from the coil to the distributor as well. :/ weird. I hate this car.

Also got my hands on a volt meter thingy. Not sure how to use it though :/

What to do next......

EDIT: for the hell of it I pulled the fuel rail off , reattached the injector ground wires, and had my bro crank it. They all squirted simultaneously twice for each turn over. A hell of a lot of gas too.

 

Pulled all the plugs again and cleaned them off nicely. the car sat for close to an hour with no plugs in it. I pulled off the air hose from the air box and from the Idle air control. I also unplugged the throttle position sensor then tried to start. For a few moments my world was like heaven. The car revved up to 3k rpm all nice and smooth then dropped back down to 750 but was jumping all over the place. it stayed there on its own for a few more moments and then died. I was kicking the throttle all over the place. I tried once more and nothing. I hooked everything back up and also nothing

This is the first time I have gotten anything out of the car since sunday. This is awesome. I have a 15 page paper due tomorrow night. Wish I had a little more time somehow.

 

Sweet success! Got the damn thing running. Took the spark plugs out again and unhooked the injectors. unhooked the turbo, unhooked all air pipes, unhooked the throttle position sensor, unhooked the air mass meter, unhooked the idle air control.

Cranked it for 45 seconds to clear everything out. Then I put the plugs back in and reattached the injectors. started up that way and held at about 2k rpm on its own. Then I slowly reattached everything back up starting from the turbo, air mass meter, throttle position sensor, air hoses and air mass meter. Its a little rough sounding but its alive!

So kids, when its dead, rip it down so that there are no funky electronics helping and then clear the cylinders out and clean the plugs and such if dirty and run it like a tractor from 1940.

 

God dammit. Drove it about 300 miles and one morning, i tried starting it and the same thing again. I pulled the plugs and all those sensors and air hoses again and cleaned it up. plugs and oxygen sensor were coal black like before. it started and ran with nothing plugged in. The difference this time is that it didn't go up to 2k rpm and stay there. It went up to 1500 ish and would jump down to 1k then back up once in a while. It was also a bit rougher sounding. I then plugged everything back in and it stalled within a minute. The rpms were jumping up and down between 400 and 1500 then it stalled and wont start anymore.

 

How fast will an oxygen sensor kick in and start working on these cars? how much control does the oxygen sensor have over fuel if everything else is unplugged?

EDIT: This is why I ask. I read someplace that after a few minutes control of the fuel mixture will switch from the air mass meter etc over to just the oxygen sensor. I let the car run without the air mass meter or idle control valve or the throttle position sensor, or air intake pipes attached and hoped the oxygen sensor would heat up and take over in a few minutes. I let it run for a good 15 minutes. It just idled really roughly and spewed greasy crap out the tailpipe covering my sisters car which was parked right behind it. It never smoothed out so I shut it down and pulled out the oxygen sensor and of course it was black again.

 

Here is another question, I put dielectric grease inside the connection where i spliced the new oxygen sensor on. I just read that it breathes down the wiring of the oxygen sensor. I wonder if it is all plugged up.

 

try taking off your timing belt cover and check to see if it is in time, when i got mine i drove it home no problem then the next day it wouldnt start..... a week later i did that ^ and it was out of time, off by 7 notches... but the belt was fine, retimed it and she worked... you may also want to clean your throttle body and intake manifold

 

Ok, did the clean up thing again. Got some electrical connector cleaner as well and cleaned up some circuits. I also installed the old oxygen sensor. I have driven it about 300 miles without it dying on my. Found a tiny air leak and its smoother than it ever has been. Took 1 freeway trip for 110 miles and i got 17 mph just like from the start. :/ so I ordered a new sensor with the wiring and socket attached.

When i ordered it I specified the type and model etc of the car but the connector is black instead of my of like my old brown one. Also there is a little chunk of plastic on the connector that needs to slide into a slot on the female connector in the car. Prob is, the chunk of plastic is on the opposite side. Would it be bad if I just ground off the plastic and used it anyways? or is there something different about this car and the oxygen sensors are different?

 

From looking around at different pictures of sensors, I'm getting the idea that the brown connector means its for EGR and the black is for cars without. Anybody have an idea if the sensor itself is different and if a modified connector would be ok?

Also, what does the EGR look like in these cars? I had assumed previously that this volvo didn't have it. My other volvo, a non turbo 94 940 has a huge flexible aluminum pipe from the exhaust manifold around the front of the block over to the air box. This new volvo doesn't have that big pipe,and the air box is on the other side.

 

all that clip thing is for is to ensure the wires stay connected. it you grind it off be sure to tape it with electrical tape. but if at all possible id suggest you not to do so,

 

Thanks for the reply! it was a close out sensor. trying to decide if I should try and return it an but one that costs 2x more, or take the chance and just use it.