Strange intermittent no start.

[streck]

A recent development in my otherwise reliable 1998 V70 T5 is that it does not want to start all the time in the morning. It started doing this about a month ago and I'm not sure what to do or really where to look.

It, literally, only seems to do this in the morning. We have had some varying temperatures with warm days and cool nights so my first thought was condensation in something electrical.

It started with a few days of refusing to start in the morning but then will fire right up in the afternoon as though nothing was wrong. Any time it starts, it runs fine; no rough idle, hard start, or anything similar. I then had a few days where it started fine in the morning but I did not drive out of fear of getting stranded.
Yesterday, it started just fine and drove it to work. This morning, no start.
It cranked fine and seem to be really close to running but just never caught. A few hours later, my wife went out and it started right up without hesitation....

Any idea? Is there a temp sensor that may be causing a fuel issue or may there be condensation getting into the distributor (what a pain to get to as I thought about looking but it seems a lot has to be removed to get to it).

Thanks for any guidance you could provide.

Daniel

[MadeInJapan]

Welcome to MVS.
Two things come to mind:
1. Ignition switch...these are prone to fail on your car after so many years...try wiggling your keys and see if it starts.
2. Bad battery leads (both positive and negative ground wires)- look for corrosion around the battery posts and follow the wires around to where they connect to other junctions...there are braided wires back behind the engine- check these out as well...take them off clean them, re-attach them.
Also, it's possible that your battery is just weak- batteries work better in warmer weather. If #1 or #2 are not the issue, have a load test done with your battery at an auto parts store- it should read about 13V or a bit more when the car is running.

[streck]

Thanks for the information. I had not thought of battery connections but that is a simple and cheap action, I should have tried it.

I had read some posts about fuel pump relays and distributor caps/rotors causing similar symptoms in similar conditions with age.

I'll try the electrical connections first and then work from there.

Thank you,
Daniel


BTW, what's MVS?

[Ozark Lee]

BTW, what's MVS?

Matthew's Volvo Site.

The next time it won't start check the fuel pressure at the schrader valve on the end of the fuel rail. The fuel pump relays get intermittent when they start to go bad.

...Lee

[streck]

The next time it won't start check the fuel pressure at the schrader valve on the end of the fuel rail. The fuel pump relays get intermittent when they start to go bad.

...Lee

And now that I'm ready to check the fuel pressure, it's starting everytime.....of course a new issue is that the cooling fan is not wanting to turn off. As soon as I turn the key (even before the engine starts), the fan comes on and stays on. Just to see how long it would run, I let it go for about 5 minutes before the fuse.
If I leave the fuse out for a minute or two, I can put it back without the fan coming on.

It seems like the temp switch for the fan is bad.

[streck]

This is getting weird. The car is starting for me each time I try but.....

When the car starts on the first try (no long cranking or second attempt needed), everything works great, as advertised.

But, sometimes it doesn't start on the first try requiring a second crank to get it started. When this happens, a few symptoms appear. First, the idle is a little rough and hunts for a few seconds. A gentle touch of the throttle gets a delayed rise in rpms but then everything settles down and idles fine. Also, during these times, the radiator fan comes on right after start up and the temp gauge rises to the 3 o clock position within 15-30 seconds of start up (this does not occur in the above normal start circumstance). If I were to drive the car, the temp gauge will rise toward the red when moving only to fall closer to the 3 o clock position when stopped at a light or in traffic.

I'm thinking I really need to clean up some grounds but was wondering if anyone has seen anything similar?

[Fleck28]

i know the cars are far apart in age and electrical systems, but this sounds very similar to my 05 xc70 starting issue...same situation, will not start (turns over great) when its a cold morning, once it warms up the car starts fine. i've left it at shops for weeks at a time hoping to recreate the issue with no luck as they cannot diagnose unless the issue is happening. i have to think this is related to either a temp sensor or possibly the ignition coil. someone recommended that there is an immobilizer on the ignition, but why would this kick in just when the temps are cold?

anyway, thought you would like to know that im sharing the same issue.

[streck]

Ha! Thanks...

It's just frustrating that I can't duplicate it....damned electron not doing what they are supposed to....

[streck]

I think I may have resolved it....Since the problem is/was intermittent, only time will tell.

It looks like it was the temp sender. In addition to the random no start, as soon as I would start the car, the temp gauge would rise to about the mid position (3 O clock) and then rise from there as the car warmed. It made it look as though the car was going to over heat. Actually checking temps under the hood verified that this was not the case. It had to be electrical.

A new temp sender fixed the erroneous indication.

Just for grins, I put in a lower threshold thermostat and replaced the distributor cap and rotor (which could have had a hand in the no start).

[howie]

I had a similar issue but one time banged the steering wheel out of frustration and it started which led to the receiver for the security chip in the key. My issue was only when the car was hot which led me to check a whole bunch of other unrelated issues. I think the fix is in the repair database.