Happy New Year guys! So, I took my 850 to work on Monday and car was running just fine. On Tuesday morning, went to start the car and it turns over but won't start. Sometimes will catch, sounding rough, for about a second then die.

I can hear the fuel pump turn on when the key is in the on position. So, I assume the fuel pump is ok and fuel pump relay is good. Is that assumption correct?

I am going to see if I can rent an inline spark tester on Saturday and ohm out the cam position sensor. Going to also replace the fuel filter since it has about 40,000 miles on it.

Anything else I should check?

 

I wouldn't rule out the fuel pump yet. In most cases sure, but a failing fuel pump can still start when you turn the key but it might not be working properly. I would check the pressure on the fuel line to see if it truly is working properly.

Otherwise your heading in a good direction.

Oh, quick thought, make sure vac lines are nice and buttoned up.

 

Good idea on the vac lines. I was planning on renting a fuel pressure gauge as well. Thanx!

 

As said, check the fuel pressure at the fuel rail. I replaced the fuel pump on my car and about a month later it died and would not start. It would kind on try sometimes. I checked the fuel pump and one of the wires had broken off at the pump, probably from torquing when the pump kicked on.

 

Well, did some testing today and this is what I have:

- Battery is good. 13 volts at battery posts and about 11.5V when under load
- Have spark at all 5 plugs
- Shrader valve spits out a good amount of fuel when I press it.

Should the RPM gauge move when the car is cranking? I've never paid attention to it before when it was working. Read that if the gauge doesn't move on some cars, it could be a bad cam position sensor. From my understanding, cam position sensor failure is pretty common on these cars. Looking through the car's records, looks to be original. Could that be my culprit?

 

Oh yeah, checked to make sure timing belt didn't snap and it looks good

 

Ok, rented a noid light to make sure the injectors were getting pulse and all 5 were. I checked the distributor cap and rotor and there are no cracks and the contacts look good. I replaced the coil since it was the original (as far as I'm aware) and still no luck.

Renting a fuel pressure gauge now but running out of ideas.

 

The battery should sit at 12.5v when off and close to that when idling. Under load a battery should be upper 13v and going as high as 14.5v. What your saying is signaling a dieing/weak alternator. Especially if your battery under load is only charging at 11.5v, just to point this out.

I would look into the Mass airflow sensor too. It will cause rough idles and stalling as well. Check the IAC as well to make sure it isnt stuck. Sometimes they get gunked up, which will cause rough idle.

 

I'll give that a shot today. Thanx

 

Ok, so it looks like the coil was the problem and the reason it didn't start May have been because the engine was flooded from all the testing? I tried cranking this morning to check something on my scanner and it started. Was really rough for about 5 seconds or so then smoothed out and ran at a steady 840 RPM at idle. I let it run for about 15 minutes then left it for an hour to get cold and tried starting again. Car started again with no problem. Just finished running a couple errands where it was stopped and started a few times and drove about 20 miles with no issues.

Tomorrow will be the true test as it supposed to get down to 8 degrees overnight and the car will be sitting outside. If it starts, I think this issue will be resolved.

 

" Battery is good. 13 volts at battery posts and about 11.5V when under load"

Voltage will tell you if a battery is bad but does not indicate if it's good. A battery can have plenty of volts and no amps so won't turn the starter.

Best way to test the battery and starter is to take them to an auto part or tire store and let them run a free load test on the battery and draw test on the starter. It's free and then you'd know.

The 11.5V under load ... are you taking about while cranking the engine without it starting or ... what load ??

What voltage do you have at the battery with the engine idling ??

 

I probably should have clarified, I was using a battery tester I have that you can simulate a load to see where the battery voltage is.

 

Ok, so here's where I am. Monday morning, super cold out and the car wouldn't start (cranked but, no start). Tried cranking about 3 times with no luck. Since it was so cold here this week, I just left it and borrowed my mother-in-law's car.


This morning, my MIL's battery is dead. Just out of curiosity (and needing to get to work), I tried starting the 850 and it fired up on the first crank and got me to the train station with no problems. It sat outside in sub zero wind chills since Sunday. What is going on? The way it is acting, I'm thinking it has to be a sensor, relay or possible a loose wire somewhere. Hoping it will start for me after work. Any ideas? Thinking I may just need to bite the bullet and take it in to a shop.

 

Hmm... only thing that I am thinking is you need to check that battery. By this I mean taking it out and heading to autozone or a place like it and actually have them test the battery. This will let you know the condition of the cells inside.

What I am thinking is that your battery might have lost a cell and you are not getting the required volts to supply the car to start it properly. On top of this, you are in extremely cold temperatures which already kills a batteries efficiency.

I am still stuck on those readings about your battery with that tester. To me it isn't right and I have a feeling might be your problem. Kiss4afrog is right to bring that up again.

 

Well, it started for me after work yesterday and got me home. This morning I tried it and no start. I took the battery back to CarQuest where I bought it and had them test it. The hand held tester said it was good. The guy asked me if I wanted them to charge it up since it was down slightly from the cold. I had him do it and after it finished charging, their unit said it was bad. Looks like you were correct about the bad cell. They gave me a new replacement and I just installed it but, still no start. It's supposed to get up to 30 here tomorrow so, I'll try it out again then. So frustrating!

 

Use a tire gauge to measure fuel pressure. It fits.

Get a good scan tool and see what temperature the ECM thinks the engine is. Coolant temperature sensors are an issue sometimes.

If you have spark, and particularly if there is no CEL, then presumably there is no reason to check sensors related to ignition.

 

Hey guys...Just an update, the car has been starting fine for me on the first crank everyday since Sunday. Still scratching my head on this one. One thing I did notice, which I don't know if this could even cause this issue was the metal of the ignition switch ( where you put your key in to start the car) had frost on it Saturday when it wasn't starting. I sprayed it with wire dry and it hasn't frosted since and the car has been starting.

I suppose it could be a bad tank of gas too? Either case, so far so good.

 

Holy ****!! I have lived in the south all my life, so I am not used to having really cold temps like the north, but your ignition switch had frost on it? That is crazy. That's inside the car lol jeez.

Just noticed what you said also. If the old battery truly was the problem, then it would make sense. Since now your car is getting the correct volts to power everything from the new battery, were as the old battery wasn't supplying the correct volts to everything.

 

did you find a solution to this issue?