1995 Volvo 850 no spark but will crank. Code P0120.

manusdei113 · Post by **manusdei113** » 16 May 2011, 22:07

OK so the core issue is that there is no spark coming from the ignition coil. Here is what I did. I replaced the cam sensor and the crank sensor as I though one of those were the issue. I tested the ignition coil and it is fine (it is getting the proper voltage). I checked all the ground wires and they are fine.

When i try to start the car, the fuel pump kicks in as you can hear the his of the fuel being pumped in. Then when I try to start it, it cranks but will not turn over at all as none of the cylinders are firing because there is no spark from the ignition coil. I found this out by taking the cord out of the distributor cap and tried to get it to arc. Nothing, no spark.

My gut tells me one of the following might be the problem: short in wiring harness, main relay, ignition switch or ECU.

Any suggestions?

Post by **Ozark Lee** » 17 May 2011, 05:18

Do you have any codes from port A-2 or A-6? If you have a turbo you won't have any reading at all from A-6.

If you have not read codes before here is how it is done:

http://volvospeed.com/CheckEngine.php

Codes help us more than just guessing.

...Lee

manusdei113 · Post by **manusdei113** » 17 May 2011, 20:48

So here is what I did today. I checked the led codes and did not get any codes from A-2 or A-6. I replaced the ignition switch and tried a new ECU, but the problem still exists. I also got an ODII sensor reader and this is the only code it shoots out. P0120.

Post by **Ozark Lee** » 17 May 2011, 21:00

P0120 is a throttle position error code, it actually causes the transmission more grief than it does the engine and it should in no way inhibit the spark.

One of the biggest problems with no spark is the cam position sensor. If it dies suddenly it will not post a code and it will also not send the "fire" signal to the coil. The error code on the cam position sensor is a real catch 22, the car will not start without the signal but the error code will not set until the engine is running and it can compare the cam and crank sensor readings.

I'm not telling you to run out and buy a cam position sensor - they are expensive - but it does warrant some additional testing and connector cleaning.

...Lee

manusdei113 · Post by **manusdei113** » 17 May 2011, 21:05

I have already replaced the camshaft position sensor. There is still no spark, granted, I might have gotten a bad sensor. I used a multi meter and here are the readings coming off the coil. Red wire 5.5 volts. Blue wire 5.5 volts.

manusdei113 · Post by **manusdei113** » 24 May 2011, 11:02

Just as an update. I have replaced the ignition coil and it still is having the same problem. Any idea anyone?

Volvowifey · Post by **Volvowifey** » 07 Apr 2019, 12:12

Just wondering if this was ever figured out?? My Volvo hubby has an 850 turbo that you hear when key turned but no start ... He has done all the changing of parts but still no spark to the new coil???

manusdei113 · Post by **manusdei113** » 07 Apr 2019, 12:18

I had this issue and ended up having a short in the harness. In order to fix it, I would have to pull the engine. Instead I sold the car. Notorious electrical issues.