Hello. Long time since I been here. I am having problems with a 1993 Volvo 850 non-turbo. The car sometimes just will not start and when it won't, I checked and found it was not getting spark. Replaced cap, rotor, plugs, wires, and coil but intermittently it won't start unless you crank on the starter for extended periods of time. Still intermittent no spark.

I ran diagnostics and found a code 2-1-4 and replaced the RPM sensor on the trans. I also routed the wiring away from any ignition wires from what I have read on this forum before, but the code keeps coming back. I notice that if I hard accel, the warning indicators on the cluster start to dimly illuminate, get brighter, and some power loss is felt. Almost like it's losing RPM signal on hard throttle.

I am not sure if the intermittent no-start is related to this, but it's driving me crazy. The car can sit for a day or two and be fine and sometimes it just will not fire unless I crank the starter for a long time, so I am stumped. Any help is appreciated.

Thanks.

 

Cam sensor good?

 

I was wondering if that may be the problem. How do I test it?

 

Well the cam sensor controls the the injectors and fuel pump.
Also check the plug they are known to fall apart.

 

I did take apart the white connector and it seems fine. I used to work on these things at a dealership, but have become quite rusty. I thought if the cam sensor was bad it would also cause no spark from the coil. Am I correct?

 

Here's a quote for 2-1-4. My service manual says it is Vehicle Speed Sensor (VSS).

1-3-1 (VSS Signal Absent) & 2-1-4 (VSS Signal Intermittent)
1) Connect measuring unit to ignition ECU. See MEASURING UNIT
under SELF-DIAGNOSTIC SYSTEM. To check VSS signal, connect voltmeter
between measuring unit terminals No. 1 and 2. Operate starter motor.
Voltmeter should indicate 300-400 millivolts with ignition switch in
START position and about one volt with engine running.
2) If voltage is not present, turn ignition off. Connect an
ohmmeter between measuring unit terminals No. 1 and 2. Resistance
should be 200-400 ohms, depending on temperature. Connect ohmmeter
between measuring unit terminals No. 2 and 20. About zero ohms should
be present.
3) Disconnect Camshaft Position (CMP) sensor connector to
prevent it from setting code. Use diagnostic test mode No. 2 and
recheck sensor signal. See DIAGNOSTIC TEST MODE NO. 2 under
SELF-DIAGNOSTICS. Operate starter motor. Code 1-4-1 should be
displayed (vehicle speed sensor). If code is not displayed, repeat
test using new ignition ECU.
4) If no electrical fault is found, ensure carrier plate is
not damaged or distorted. This problem, which applies primarily to A/T
vehicles, can prevent engine from starting and set a code.

I hope this is of some ref until Tech comes home.


JPN

 

I just replaced the cam sensor (expensive little part) and the car will not start right now, so I will investigate the VSS now.........

 

I have so far replaced the RPM Sensor, the cam sensor, and today the VSS and the car still will not start. I just checked and there are no current codes coming back since parts replacements.

I seems to crank funny making me wonder if it's a compression or fuel problem. It's weird how it will not start for 2-3 days and then one day it fires up like nothing. The damp weather seems to be a factor since it always starts when it's nice and dry out.

Any other ideas? I am not throwing any more parts at this. I talked to an old fellow Volvo tech and he said the 1993 system was used for a short time and he's not really familiar with pre 1994.5 systems, but he mentioned a red colored fuel pump relay under the fuse box that could be the cause of the intermittent dash lights illuminating and low power on hard accell? I don't know what to do. Tomorrow I am bringing home the compression tester and the fuel pressure gauge again.

If you guys have anything else to suggest, I'm all ears.

 

Does the car have the injector relay on the cooling fan?
Also if you can check for injector pulse as well.

 

I will have to go out and look. I am not sure what I am looking for though.

I will bring home a noid light for injector pulse.

 

There is a relay almost like the 740 injector and cooling fan relay. But it is on the top of the radaitor. It is also gray.

 

The relay connections checked out good. Once the weather got warmer, the car starts up every time and has showed no signs of problems for 3 days. If it ain't broke, I can't fix it, so I returned it to the customer. He will inform me if the issue comes back.

Seems that it's either the ignition or ECM being affected by cold, damp weather. Odd issue if you ask me.

 

Yes Odd!!

 

ok wierd!!! I was having some stalling problems on my 850 glt

I noticed it was difficult to start or odd in the cold or damp and the other day it was a monsoon outside storming heavily and the car wouldnt start at all!

Long cranking with coughing and occasional sputtering but no start Its been two days now and Im going to go try it out and if it wont start ill start trouble shooting again.

 

I used to have a slogan.............

"I always Win"

Well after 20 years of winning, unfortunately, I lost for the first time ever and it was on this car. After multiple attempts to fix it for free, he ended up taking it to a dealership. Apparently they found a bad wire that goes to the coil and whacked him about $600.00 for the repair. I replaced the coil and found no issues there, but it could have been in the harness out of sight.

 

Tracing a faulty electrical wire(s) is one of the most difficult tasks in any form of transportation maintenance (and we'll be getting more hybrid/electrical vehicles/aircraft).

TWA's flight 800 (B747-100) out of JFK was killed by fuel quantity signal sending wire that was exposed from the insulation, which in turn touched the airframe, caused spark and ignited the centre tank that had very little fuel left but lots of fuel vapour. No technician was able to find it, as that part of the airplane does not receive inspection often.

The dealer was able to skip all the steps you had taken (the owner must have told them all the previous works done to the car) and that saved them from trouble & wasted time. You may think you've lost, but I look at it as you did most of the work and the next guys were helped by you.


JPN

 

I actually printed up a detailed list of what I have done to the car and all the parts that were replaced to aid the Volvo tech in his diagnostics.

 

I was right, you did the majority of the job so the dealer was able to save much time troubleshooting. You're definitely a top-notch technician.


JPN

 

Johnny what have you done to your car when you said that cost's you about 600$ the repair because I have the same problem with my volvo 850, I have no spark and it won't start in cold days, when the winter is coming I can't start my car, in the summer I have no problem.

 

"they found a bad wire that goes to the coil"