My Mom has a 1996 850 Turbo. For some reason, it has a hard time starting after being driven in warmer weather (70 degrees). Starts fine when cold. Runs fine after being started. Example, if you drive it for 10 minutes, then go into a store or to eat for an hour, it won't start until it cools down completely. She has taken it to the local (non-dealer) Volvo repair garage twice and the mechanic indicates that he cannot reproduce the problem.

Has anyone had any experience with this problem/solutions?

JPG

I had a similiar scenario and it turned out to be the cam sensor(cam alignment sensor?). Replaced the sensor and all is now well. I was throwing the check engine light.

Good luck

Had a similar problem with a 98 Ford contour but the car would start when cold and once warned up it started fine, let itr sit over night and it would not start or be very hard tpo start the culprit was the Crankshaft Position sensor. had it replaced and had not the problem since.

Sensors can cause this type of problem, once the sensor cools off and the circuit in the sensor opens or closes the problem goes away, or show up whe the sensor get hot and the circuit opens or closes.

Good luck, any check engine light?

this sounds like the same problem I am having with my 93. Most of the sensors on my car are changed and the problem persists. I noted a previous response to your query, i.e. that it could be a cam sensor. I would not think that a cam sensor would lead to an intermittent problem, if the cam sensor does not work, the engine does not know when to fire and it dosen't run -period. I did have the RPM sensor changed and this may have helped a little but not totally. One other thing to check would be the engine temperature sensor, although in my case that did not help. When my car engine is around room temperature, I start the car by holding the acclerator to the floor (hold and keep it there, do not pump)and cranking the engine. After turning over 6 or 7 times the engine catches. It appears what is happening is the engine when at room temperature does not supply enough air and keeping the foot on the accelerator overcomes the problem.
Let me know if you solve this problem, cheers

Well, you obviously know it is a temperature related problem. And being a no-start, it is probably either ignition or fuel. What I would do if I didn't feel like getting my hands dirty, is take the car to a Volvo licensed dealership. If you have some experience working on fuel and ignition systems, I would suggest doing some probing with some dry ice or ice cubes. Basically, warm up the car, and get the car to the point that it will not restart. Then systematically, use dry ice preferably, cool select systems one at a time, until you find the culprit. As you descriebd, it takes about an hour or more before you can start the car. Thus, if you cannot start the car after you have cooled a particular system, that system is not the cause.

But before you do the probing, I would suggest doing a disassembled visual inspection of your ignition system. Look at things like the distributor, cap, the wires, the plugs, etc. Also, use a multitester to check for continuity or lack thereof, of various components. Temperature changes cause expansion, and contraction, and these changes can cause circuits to open and close when they are not supposed to.