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I cleaned out the EGR valve, and for that I removed the radiator fan (disconnected all the relays), removed throttle body and starter too. Upon assembly this morning, in my rush to put it back together I neglected to connect the throttle position sensor. Connected everything else, connected the battery and tried to start the car. It coughed once and after the starter cranks and cranks but it does not even try to start. Checked the codes on A2, it gave me 4-1-1, something about TPS exceeding voltage. I cleared the code. I have gone over everything, checked all the connections but the car does not start. Any suggestions (besides not rushing when putting things back together)?
Charlie
'94 855
'88 244 (Thankfully it runs)
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Thank you Jadnhm, yesterday I ordered a little fuel injection pressure gauge, so in a few days I will be able to check that. The pump does go through the priming cycle when the switch is in position II, and I cannot imagine why the pump would quit working while I worked on the EGR. The car cranks as if the coil was disconnected, not even a snap, crackle or pop. But my timing light shows there is spark. That is why I think the injectors are just not opening, because if they opened or even leaked, there would be at least some pops and coughing.
My motto is similar to Edison's; "I have not failed, I just have not figured out why this is not working!". Here are my next steps;
1. Disconnect the MAF sensor, crank and see if it goes in limp-home mode. My 240s all had the wire-type MAF, but this one apparently is different (It can even be cleaned!).
2. Recharge the battery
3. Check the starter; although I had never heard the car crank without starting, it seems like it cranks slow. I read somewhere that the motor has to spin above 250 rpm before there is spark and fuel (But there is spark, so this may be redundant)
4. Check the fuel pressure when I get the gauge
5. I have not been able to find anywhere what sensor triggers the spark and what sensor triggers the injectors. I suspect the crank position sensor is the one that triggers the spark, and it would make sense that the cam position sensor trigger the injectors. That would narrow the search. Worse comes to worse, I am picking up a cam sensor at the U Pull it just to be safe.
I will figure it out sooner or later. Thanks to all for all your ideas.
Charlie
'94 855
'88 244
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Charlie,
Pull one or two of the spark plugs and see if they are wet or black. That will tell you if fuel gets to the cylinders.
Get the battery up to 12V, it won't hurt to do that. Below 10V, your car won't start unless everything is perfect.
The cam position wire must be below the distributer cap, make sure it is not running across on of the plug wires. A hot plug wire can mess up the CPS voltage readings.
If you have a multimeter, check the resistance on the CPS plug. It should be below 1500(?) but not 0.
Klaus
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I am not a mechanic, so can you trust what I type?
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I am running out of options folks. Here are further checks;
Cranking voltage? Good (over 10.5V)
Tach needle does not move while cranking
I got excited thinking I may have damaged the wire or connection to the crank position sensor or the cam position sensor, but both seem to be untouched, Is there a way to verify those two are operating? That was my last hope, that maybe the injectors are not squirting because the ECU does not know the motor is spinning. But I do not see any apparent damage there. And after cranking a few more times, I still do not get any trouble codes on A2 or A6. This is so strange that the car was running perfect when I parked it to clean the EGR, now I have a clean and shiny EGR in a car that does not want to run!! Tell me something I am missing, because there is no more info in the Haynes manual.
Thanks
Charlie
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If it were me I think I'd check the fuel pressure first. Even if there is fuel in the rail it needs to be above a certain pressure before the injectors will work. Remember that the injectors are really just a valve and your fuel pump in the tank provides all the pressure.
Can you hear the fuel pump running when you turn the key to pos II? What if you turn the key from 0 to II back and forth a few times to let the pump prime the line with pressure?
I don't know much about the EGR because my car has a turbo and therefore doesn't have one... It certainly seem suspicious that you would park the car running fine, play with the EGR and then it won't run right - it does seem to point to something that occurred during that job....
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1998 V70 AWD Turbo 195k+
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posted by
someone claiming to be fixit2002
on
Mon Sep 14 03:07 CST 2009 [ RELATED]
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It seems from what I've read here that when these engines don't start after alot of cranking they somehow loose alot of compression which then makes it that much harder to start. Maybe squirting a little oil in the plug holes would bring it back up for a while which may help.
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No Klaus, I did not have a reason to disconnect plug wires. Besides the vacuum connections and electrical connections at the relay panel, the other connections that I unplugged (and now have checked to make certain they are plugged properly) are;
The 2 wire connector going to the EGR valve and the vacuum line
The plug at the TPsensor and 2 vacuum lines under the throttle body
The plug at the air mass sensor (by the air filter)
The connector to the fan motor (so i could remove the fan)
I also removed the large positive connections at the starter (3 wires)and the "start" wire plug. Since the car is cranking, I am assuming these are good.
I disconnected the coil wire to open the air cleaner box, but since i am getting spark, I am assuming this is good too.
It took me a while to get the EGR valve out, so all in all the battery was disconnected for about a week. When I connected it and tried to crank the first time, in the position II of the switch all the lights came on, including a flashing arrow that I had not seen before. It started for a second, sputtered and died. Once I realized the TPS was disconnected and fixed that, I tried again and now the dash lights look normal, the arrow is not flashing anymore. I found some reference to the PNP switch on Bay13, but I went and checked again the transmision codes, it gave me again 2-1-3, but not the switch code.
In closing, I had never heard this car crank without starting before, so I have nothing to compare, but my impression is that it cranks slow. The battery measures 12.5 volts, I did not measure the cranking voltage. I saw among the codes in the book that there is one for low battery voltage, but I am not getting that one.
My reputation as the "Volvo guy" in my street would suffer a big setback if anyone sees my 855 wagon being towed to the mechanic, so I am determined to fix this one. Since it was running a week ago when I tore it up to fix the plugged up EGR, it can't be anything major ( I hope!).
Charlie
'94 855 sleeping beauty
'88 244 i run, i run, so off to work i go!
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Did you by chance unplug the plug wires from the distributer cap? If you did, Haynes has it wrong. The dark spot is #2, not #1. So #3 is at 12:00.
Klaus
--
I am not a mechanic, so can you trust what I type?
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Thank you Klaus. After regaining my composure today, I went and did the following;
1. Put the key in position II, there is definitely humming from the back for a couple of seconds, second time I turned the key from outside the car and ran to the front, there is definitely the "whoosh" sound of fuel flowing for a couple of seconds.
2. I connected my inductive timing light, cranked again, there is definitely spark.
3. I checked again for trouble codes in both A2 and A6, no trouble codes stored.
What am I missing? In Spanish there is a proverb that applies to the Haynes manual, "that and nothing equals two nothings". My only conclusion is that the injectors are not opening. I had the bright idea that it may be some sort of antitheft mechanism, so with the remote I locked and then unlocked the car again, but unfortunately, no luck, crank, crank, crank, but no start. Sounds like another week driving the trusty 244!
Charlie
'94 855
'88 244
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Unplug the TPS again, clean the connection, and plug it back in - make sure it seats correctly.
Did the fuel pump whine when you turned the key to posII?
Klaus
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I am not a mechanic, so can you trust what I type?
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